identifier: Timbal, Nicolai Adrian <https://research.library.mun.ca/view/creator_az/Timbal=3ANicolai_Adrian=3A=3A.html>   (1992) Serpentinization and carbonatization of tectonic melanges in the Coy Pond Complex, Central Newfoundland.  Masters thesis, Memorial University of Newfoundland.

abstract: Mount Cormack Terrane, an elliptical tectonic window in the Dunnage Zone of central Newfoundland, is a structural dome comprising a central zone of variably metamorphosed metasediments surrounded by remnants of several ophiolitic complexes including the Coy Pond Complex, the subject of this study. The ophiolite complexes have been interpreted to represent remnants of the early Paleozoic Iapetus ocean floor, which was obducted onto the continental margin of Gondwana. -- The Coy Pond Complex, is an imbricated, but complete ophiolite which is oriented subvertically and dips and youngs outward from the tectonic window. -- Analyses of relict olivines, pyroxenes and spinels in the Coy Pond Complex indicate that it has an arc-related petrogenesis. -- The Coy Pond Complex is composed of two structural slices separated by two tectonic mélanges. From west to east the principal structural elements are: (i) basil structural slice composed of harzburgite and dunite; (ii) western tectonic mélange; (iii) central structural slice comprising pyroxenite, gabbro-diabase, pillow lava and sedimentary rocks; (iv) the eastern tectonic mélange. -- Locally the basal structural slice is missing and its place is taken by the mixed lithology slice, which is composed of exotic (i.e. non-ophiolitic) lithologies that were probably derived from the tectonically overlying and underlying units. -- The tectonic mélanges, are composed of ultramafic fragments up to 2 m in longest diameter enveloped in an ultramafic matrix. They display evidence of brittle (fragments) and ductile (matrix) deformation and are interpreted to have formed during fault movement and emplacement of the ophiolite. On the basis of the lithologies of the fragments, the tectonic mélanges are interpreted to have formed from the transition zone (dunite) and upper part of the mantle tectonite (harzburgite). -- Both fragments and matrix in the tectonic mélanges are extensively serpentinized and variably carbonatized. Petrographic evidence indicates that serpentinization initially involved hydration of the peridotite and formation of a pseudomorphic assemblage of lizardite ± brucite. Subsequently most of the original lizardite recrystallized to antigorite and to schistose serpentinite in the matrix. Veins of chrysotile are rare. -- Carbonatization resulted in replacement firstly of brucite by magnesite, and subsequently of the serpentine assemblages (lizardite and/or antigorite) by magnesite ± talc. Later, quartz-magnesite formed by replacement of talc or by breakdown of remaining lizardite. These assemblages indicate a progressive increase in XCO₂ in the fluid phase during formation of the metamorphic assemblages with temperatures <300ﾟC for quartz-magnesite and >300ﾟC for talc-magnesite assemblages. -- Carbon and oxygen isotopic compositions of magnesite coexisting with lizardite, antigorite, talc and quartz were measured from the eastern and western tectonic mélanges. δ¹³O values of magnesite vary only slightly, from 12.3 to 17.5, with higher values occurring in the quartz-magnesite assemblages. δ¹³O values show considerable variation in isotopic composition from -4.2 to -9.1 for magnesite associated with lizardite and talc, from -10.8 to -13.6 for magnesite associated with antigorite, and from -11.9 to -20.4 for magnesite associated with quartz (in the western tectonic mélange). These data are interpreted to indicate that the different magnesite assemblages formed from different carbon reservoirs, with magnesite associated with lizardite and talc having an oceanic and/or average crustal carbon isotopic signature, whereas magnesite associated with antigorite and quartz shows a progressively more organic (continental) carbon isotopic signature. -- Structural, metamorphic and isotopic information have been used to construct a tectonic model for the formation and evolution of the tectonic melanges, which involves several stages. -- (a) Early serpentinization of dunites during detachment of the ophiolitic nappe. -- (b) Initiation of the formation of the tectonic mélanges during imbrication? and obduction of the ophiolite nappe onto the continental margin, together with partial carbonatization. At this stage magnesite associated with lizardite and with talc was formed. -- (c) Emplacement of Coy Pond ophiolite on top of the continental margin, consisting of Spruce Brook Formation. -- (d) Extension of the continental margin induced heat transfer into the tectonically underlying sediments (Spruce Brook Formation) which were affected by a low-P metamorphism. -- (e) This induced isostatic instability in the lower crust, with mechanical and thermal doming of the Mount Cormack Terrane, followed by renewed imbrication and final emplacement of the Coy Pond Complex, by extensional faulting, into its present subvertical orientation. It is assumed that the formation of the tectonic mélanges was concluded during the extensional faulting, when magnesite associated with antigorite and with quartz assemblages was formed in equilibrium with fluids carrying carbon of organic origin.


identifier: Talkington, Raymond W. (Raymond Willis) <https://research.library.mun.ca/view/creator_az/Talkington=3ARaymond_W=2E_=28Raymond_Willis=29=3A=3A.html>   (1981) The geology, petrology and petrogenesis of the White Hills peridotite, St. Anthony complex, northwestern Newfoundland.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

type: Thesis NonPeerReviewed

format: application/pdf application/pdf

abstract: The White Hills Peridotite is located at the northernmost tip of the Great Northern Peninsula of Newfoundland. The peridotite is the highest structural slice of the Hare Bay Allochthon and outcrops as three massifs (two large and one small) which may represent dissected parts of a once complete ophiolite complex tectonically emplaced during the Mid-Ordovician as a result of the closing of the Iapetus Ocean. -- The peridotite is made up of an interlayered sequence (1 mm to ½ m) of spinel lherzolite and harzburgite (~ 85%), and dunite that occurs as layers, dikes and lenses which either parallel or are oblique to the lithological layering. High-alumina pyroxenite veins (orthopyroxenite, websterite, wehrlite, and clinopyroxenite) are ubiquitous, whereas gabbro veins are restricted to the eastern section of the eastern massif. Chromite-related lithologies (low-alumina orthopyroxenite, low-alumina "websterite", and chromitite) are common to the eastern massif. The vein material is concordant with or discordant to the lithological layering. -- At least two major deformational events have affected the peridotite, F₁ and F₂. F₁ is tentatively interpreted to be the result of high temperature plastic flow of the peridotite during its ascent below an accreting ridge and during this event the orthopyroxene-foliation may have developed. F₂ is interpreted to have formed during the tectonic emplacement of the peridotite. An F₃ deformational event only slightly affects the peridotite and is post-emplacement, probably an Acadian feature. -- The bulk rock chemistry for the White Hills Peridotite is similar to other ophiolites and subcontinental upper mantle material. There are, however, several internal geochemical differences which distinguish the various White Hills lithologies, especially the pyroxenite (all types) and gabbro veins. These differences are predominantly in the TiO₂ and Al₂O₃ contents of the constituent minerals. On the basis of mineral and bulk rock geochemical differences, at least two geochemical trends are inferred, and at least two distinct, yet genetically related, liquids are required to explain these differences. Most of the minerals of the peridotite show the effects of subsolidus mineral-bulk rock equilibration, although to various degrees. -- The petrogenetic model proposed for the White Hills Peridotite envisages at least two major partial melting events one at moderate to high pressures, the other at low pressure. The first liquid, an olivine tholeiite (first-stage liquid), is derived by approximately 20 percent partial melting of the spinel lherzolite source at high pressure (~ 20 kb). The second liquid, a magnesian-quartz tholeiite (second-stage liquid), is derived by approximately 5 to 10 percent partial melting of the previously melted spinel lherzolite source at low pressure (≲ 8 kb). The partial melting residua produced after the first- and second-stage melting are a clinopyroxene-poor lherzolite and a highly refractory harzburgite, respectively. Polybaric crystallization, from approximately 20 kilobars to approximately 10 kilobars, of the first-stage liquid results in the formation of some dunite and high-alumina pyroxenite (orthopyroxenite, websterite, wehrlite, clinopyroxenite) and gabbro veins. Crystallization of the second-stage liquid at low pressure produces the chromite-related lithologies (low-alumina orthopyroxenite, low-alumina "websterite", chromitite). -- The White Hills Peridotite represents a sample of upper mantle that preserves a variety of features and processes resulting from a hypothesized off-axis ascent trajectory.


identifier: Peng, Zhengrong <https://research.library.mun.ca/view/creator_az/Peng=3AZhengrong=3A=3A.html>   (1990) Subseismic description of the Slichter modes in a rotating Earth.  Masters thesis, Memorial University of Newfoundland.

abstract: This thesis reports a study of the triplet of (purely translational) Slichter modes of inner core oscillation for a simplified uniformly rotating Earth model with spherical elastic inner core, spherical rigid fixed mantle and neutrally stratified, compressible liquid core. A variational principle is used to solve the subseismic wave equation, which is used to model the liquid core dynamics. The investigation shows the utility of the subseismic wave equation for describing a long-period oscillation, with the effects of higher order harmonics in the displacement field taken into account. For the first time, a numerical estimate of error involved in making the subseismic approximation is given for a particular mode. The eigenperiod of the Slichter mode is found to be around 5 hours for neutrally stratified liquid core with total mass constrained by PREM (1981) data. The effect of the Earth's rotation is to split the mode into a triplet with eigenperiods 12% shorter, 2% shorter, and 10% longer. The effects of compressibility of the liquid core and elasticity of the inner core are to increase the eigenperiod by about 0.6% and 9% respectively. The study can be regarded as a preliminary numerical attempt to describe gravitational/inertial oscillations of the Earth by the subseismic wave equation.


identifier: Brydie, James Ronald <https://research.library.mun.ca/view/creator_az/Brydie=3AJames_Ronald=3A=3A.html>   (1995) Geology and geochemistry of magnesite occurrences, Akamas Area, Northwest Cyprus.  Masters thesis, Memorial University of Newfoundland.

abstract:
A complex Late Cretaceous suture zone between two distinct geological terranes is preserved in southern Cyprus in a series of erosional windows through Tertiary-Recent cover sediments. The two terranes are the Mamonia and Troodos Complexes, and the suture zone contains evidence of two major contractional tectonic events - primary north-northeast- and secondary west-southwest-directed thrusting. Delamination of the Mamonia Complex during juxtaposition against the Troodos Complex resulted in Mamonia rocks being thrust beneath and over the Troodos Complex Later west-southwest-directed back-thrusting resulted in imbrication of the Troodos Complex and also Mamonia rocks being thrust over Troodos rocks (Malpas et al., 1993). The serpentinite sheet containing magnesite mineralisation was tectonically emplaced from east to west over sheeted diabase dykes and lower- and upper pillow lavas during this latter contractional tectonic episode. -- Magnesite deposits are found in a large sheet of serpentinised harzburgite in the Akamas Peninsula and trend north-south along a 5km line adjacent to Tertiary limestone cover. The largest magnesite occurrence, the Magnisia mine, exhibits many clues to magnesite vein genesis prior to, and during, the tectonic emplacement of the serpentinite. Several temporally and spatially related generations of magnesite are identified. The magnesite deposits contain two distinct styles of mineralisation within the serpentinite, and have been divided into Zones i and II. Zone I encompasses veins and stockwork magnesite and Zone II contains nodular magnesite. Antitaxial magnesite veins have mineralised serpentinite along planes of weakness, encapsulating serpentinite fragments and exhibiting classic features associated with vein minerals formed in active shear zones, i.e. well developed median lines in veins, comb textures, brecciated veins recemented by further mineralisation and spalled wallrock lying parallel to the edges of vein walls. These veins are interpreted as having formed during emplacement of the serpentinite, and define the main phase of magnesite mineralisation. The magnesite veins and stockworks define Zone I style mineralisation. Voids within these magnesite veins have subsequently been filled by epigenetic calcite and dolomite, probably derived from solutions passing through the limestone cover above the deposits. A later generation of magnesite is present within sheared serpentinite above the veins and stockworks. This carbonate is present as a replacement style of mineralisation with magnesite nodules prominent in a sheared, carbonatised serpentinite matrix. This magnesite defines mineralisation of the Zone II type. -- Petrographic examination and chemical analyses of magnesite and associated lithologies provides further clues to magnesite genesis in the Akamas area. Stable isotope analyses of magnesite, calcite and dolomite show two distinct populations of magnesite with a singular source of carbon, one precipitated around 165°C (veins and stockworks) and the other around 40°C (nodular magnesite). Calcite and dolomite from overlying karst sediments lie in an isotopic field comparable with typical marine carbonates. Trace element analyses of magnesite, calcite, dolomite, serpentinite and organic-rich sandstone samples indicate calcite, dolomite and serpentinite to be unlikely sources of carbon present within the magnesite. From isotope and trace element data, the source of carbon within the magnesite is likely decarboxylation of organic material. -- A suggested model for magnesite formation would be as follows. Magnesite veins were formed during the initial disruption of the serpentinite, probably initiated by the production of CO₂ upon decarboxylation of organic-rich sediments underthrust beneath the serpentinite. The earliest magnesite veins were then brecciated by continued compressional tectonism and cemented by further cryptocrystalline magnesite precipitation. The serpentinite (including magnesite veins and stockworks) was eventuallv emplaced westward over gabbro and sheeted diabase dykes resulting in the formation of a
prominent c-s shear fabric present at the base of the serpentinite. Thrusting also resulted in the formation of an intra-serpentinite shear zone which was mineralised by nodular magnesite, defining a later generation of magnesite formation. No magnesite veins are present in this shear zone. Isotope data suggest a similar source of carbon for both veins and nodules but veins were precipitated at elevated temperatures, while nodules were formed at lower temperatures. The magnesite nodules are most likely a result of remobilisation of vein material followed by precipitation as nodules in the overlying shear zone. -- Recent precipitates of magnesite and dolomite around the study area may be the continuance of magnesite mineralisation.


identifier: Clark, A. M. S. (Anthony Miles Stapelton) <https://research.library.mun.ca/view/creator_az/Clark=3AA=2E_M=2E_S=2E_=28Anthony_Miles_Stapelton=29=3A=3A.html>   (1973) A reinterpretation of the stratigraphy and deformation of the Aillik Group, Makkovik, Labrador.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: The Aillik Group of Aphebian volcanic and sedimentary rocks is situated in the Makkovik Sub-province of Labrador, north of the Grenville Front. Its lithology, in the vicinity of Makkovik, has been completely reinterpreted and the first formal stratigraphic subdivision of the group defined, with introduction of new names. The previously unrecognised sequence of deformational events and associated metamorphism has been delineated. -- The 8500 m. (25,000 ft.) thick Aillik Group consists of cratogenic flow-banded and porphyritic rhyolite lava's, (previously mapped as quartzites), minor interbedded basalt lavas, polymictic and rhyolite conglomerates,and quartz-poor arkoses (also previously mapped as quartzites). The group is subdivided into six formations. The lowest (Nesbit Harbour Formation), comprising 800 m. to 2000 m. (2400 - 6000 ft.) of conglomerate with minor arkoses and basalt lavas, is conformably overlain by the Makkovik Formation of 2000 m. to 7000 m. (6000 - 21,000 ft.) of rhyolite lavas, with minor tuffs, conglomerates and arkoses. This is conformably overlain by two stratigraphically equivalent (?) formations:- the 2000 m. (6000 ft.) thick Pomiadluk Formation of interbedded rhyolite, conglomerate and tuff in the northeast; and the 2000 m. (6000 ft.) thick Manak Bay Formation of arkose and minor basalt lava in the southeast. -- West of this sequence, and separated from it by a major tectonic slide (and the associated, structurally defined, Ranger Bight complex of amphibolites), is the 3000 m. (9000 ft.) thick Big Island Formation of interbedded rhyolite, arkose, conglomerate and basalt lava. -- The Aillik Group is intruded by several major syntectonic granitic to gabbroic plutons including a large, rhymically layered, hornblende gabbro (appinite?) intrusion, the Adlavik Igneous Complex. -- Four deformations are recognised, of which the second produced penetrative fabrics and large, upright, northeast trending, folds. The others developed only local structures and fabrics, and one major interference dome. The second deformation resulted in different amounts (r = 1 to 5) and types (k = 1 to oo ) of strain, (which is not lithologically controlled), in different areas. The entire area is shown to possibly occur within a major zone of strike-slip (simple-shear) movement. -- Metamorphism has remained in the amphibolite and greenschist facies throughout tectonism. -- The Aillik Group is unconformably overlain by the Jurassic Ford's Bight Conglomerate.


identifier: Ostrom, Margaret Harrigan <https://research.library.mun.ca/view/creator_az/Ostrom=3AMargaret_Harrigan=3A=3A.html>   (1990) Geochemical characterization of high molecular weight organic material isolated from late Cretaceous fossils.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: This study reports the first carbon and nitrogen isotope and amino acid analyses of high molecular weight (HMW) organic material isolated from bones and teeth of reptiles from Late Cretaceous vertebrates (Judith River Formation, Alberta). These data assist in the evaluation of indigeneity of the HMW component and assessment of trophic structure among the Late Cretaceous consumers. Amino acid analysis of the HCl hydrolyzates of these samples show an abundance of glutamic acid and glycine. The apparent presence of hydroxyproline and hydroxylysine in some samples coupled with the high concentration of glycine suggests that a remnant of the original organic material has been retained. -- Ratios of the D- to L- enantiomer of amino acids values are less than 0.25. This may result from incorporation of the amino acids into high molecular weight organic components. Differences in amino acid patterns and enantiomer ratios between the organic fraction from fossils and associated sediment argues against contamination. -- Stable carbon and nitrogen isotope values of the vertebrates range between -27 and -23°/oo and -1 and 12°/oo respectively. The δ¹⁵N of consumers increase with trophic level. Within the terrestrial and aquatic habitats, δ¹⁵N among some of the more predominant vertebrates increases in the order panoplosaur < hadrosaur < ceratopsid < tyrannosaur and Aspideretes < champsosaur < crocodile < plesiosaur, respectively. These isotope signatures and trends in nitrogen values are typical of large modern herbivores and carnivores and are consistent with previously held views of the ecology of these organisms. The amino acid and isotope data suggest that a biochemical signal may be maintained throughout diagenesis. Such a signal could provide exciting new information pertaining to the comparative biochemistry, metabolism and ecology of fossil assemblages.


identifier: Ma, Cuiyan <https://research.library.mun.ca/view/creator_az/Ma=3ACuiyan=3A=3A.html>   (1996) Continuity of sandstone beds in the Ordovician Cloridorme Formation, Gaspé Peninsula, Quebec.  Masters thesis, Memorial University of Newfoundland.

abstract:
The objectives of this thesis are to re-evaluate the continuity of sandstone beds and to investigate the factors that control sandstone bed continuity in the Cloridorme Formation. The study was carried out in a 5 km-long strike exposure of unit G of the β7 member of Enos (1965) between Grande-Vallée and Petite-Vallée. -- Thirteen facies and four facies associations were recognized in the field. The thirteen facies are: (1) coarse- to fine-grained, graded sandstones; (2) "slurry" sandstone beds; (3) sandstones containing abundant shale clasts; (4) sandstones that feed injections; (5) sandstones with shallow erosional bases; (6) cross laminated or/and parallel laminated sandstones or siltstones; (7) thinly bedded, laminated sandstones or siltstones; (8) sandstones containing large laminated slabs; (9) sandstones with bidirectional paleoflow indicators (Megaturbidite); (10) bi-partite sandstones; (11) thinly bedded sandstones; (12) concretions; and (13) laminated, silty mudstones. -- The four facies associations are: (1) erosively based sandstone packets; (2) sandstones interealated with mudstones or siltstone; (3) interealated sandstones, siltstones and silty mudstones; and (4) silty mudstones interealated with siltstones or sandstones. -- The interpretation of sandstone facies and facies associations described from the β7 member suggests that these turbidites accumulated in the distributary channels, the outer fan, and the fan fringe of a transverse fan near the margin of the foreland basin, and on the adjacent basin plain. The proximal parts of the marginal fans are believed to have been destroyed by later tectonic uplift and erosion. -- The turbidite succession, where bed-by-bed tracing is possible, contains outer fan and fan-fringe deposits of a transverse fan, and basin-plain deposits. The lateral correlation of individual beds proves that the continuity of sandstone beds in this succession is extremely low. Only 27 of the 94 traced beds extend beyond 3 km. The relationship between bed length (L) and percentage of beds longer than L (Y) is defined by the following equation: -- Y(%) = -49(log L) + 200; r² = 0.98 -- Extrapolation to Y=0% suggests that all beds are shorter than 12 km along this two-dimensional outcrop, although inclusion of partial beds in the regression analysis means that this is a minimum estimate of maximum bed length. -- Nine types of sandstone bed terminations were identified. They are; (1) beds feeding injections; (2) sills; (3) gradual taper; (4) scour-and-fill geometry; (5) erosional truncation; (6) depositional mounds; (7) shale-clast "nests"; (8) faulting; and (9) gradual passage into shale. The percentage of discontinuous beds accounted for by these type of terminations are follows: (a) scour and focussed deposition in scours (Types 4 and 5), 44.6%; (b) depositional thinning on unscoured surfaces as a result of patchy deposition (Types 3 and 6), 24.4%; (c) liquefaction and sand redistribution
(Type 1), 10.8%; (d) masking of bed continuity by extensive "nests" of shale clasts (Type 7), 10.8%; (e) apparent lateral changes in the texture of watery debris flows (Type 9), 8.1%. -- The study of bed terminations suggests that the major factors controlling sandstone bed continuity are depositional and fault-controlled sea-bed morphology, and tectonics of the depositional setting. Sandstone bed continuity depends strongly on the rates and magnitudes of sea-bed deformation, the frequencies and magnitudes of the earthquakes that are inferred to have liquefied many of the Cloridorme Formation beds, and proximity to the termini of shifting feeder channels. Knowledge of the tectonic setting alone is not enough to permit a reliable prediction of sandstone bed continuity.


identifier: Al, Thomas Anthony <https://research.library.mun.ca/view/creator_az/Al=3AThomas_Anthony=3A=3A.html>   (1990) The character and setting of gold mineralization associated with the Betts Cove complex.  Masters thesis, Memorial University of Newfoundland.

abstract: The Ordovician Betts Cove ophiolite is located in northeast Newfoundland on the southeast side of the Baie Verte peninsula, between the communities of Tilt Cove and Nippers Harbour. Ultramafic rocks occur at the base of the ophiolite in fault contact with the upper ophiolite stratigraphy (mainly pillow lava) to the south. North of the ophiolite, intermediate and felsic volcanic and sedimentary rocks of the Silurian Cape St. John Group, and the Cape Brule Quartz-Feldspar Porphyry are in fault contact with the ultramafic rocks. Locally the Cape St. John Group unconformably overlies the ophiolite. -- Fresh, cumulate ultramafic rocks are altered to carbonate-bearing assemblages. The onset of carbonate alteration is marked by a serpentine-magnesite assemblage which appears where fresh ultramafic rocks are cross cut by shear zones. Serpentine-magnesite reacts to form talc-magnesite with progressive shearing. Talc-magnesite is the most abundant ultramafic rock type present in the area. Localized quartz-hematite-dolomite alteration assemblages with minor fuchsite are present. -- Two types of gold mineralization are described. The first type occurs in a talc-magnesite host and consists of a simple quartz, magnesite, Cu-sulphide mineralogy. The second type is hosted by the quartz-hematite-dolomite altered ultramafic rocks and shear zones within the Silurian Cape St. John Group. These Au-mineralized veins consist of quartz, ankerite, fuchsite, and specularite plus or minus magnetite and Cu-Fe sulphides. -- Gold enrichment in the ultramafic rocks is associated with regional scale carbonate alteration. This link is important for defining exploration targets. Rare earth element and Sr isotope evidence implicate an ultramafic source rock and a fluid derived from hydrated ultramafic rocks (Ordovician seawater). -- Mineralization probably occurred as a result of metamorphic dehydration of serpentinized ultramafic rocks during Acadian Orogenesis. Faults on the margin of a caldera complex to the north, and older structures related to obduction of ophiolitic rocks during the Middle Ordovician, probably acted as fluid conduits.


identifier: Fidan, Erkan <https://research.library.mun.ca/view/creator_az/Fidan=3AErkan=3A=3A.html>   (1996) Reservoir characterization of the Hibernia formation, Jeanne d'Arc Basin, Grand Banks, Newfoundland.  Masters thesis, Memorial University of Newfoundland.

abstract: The offshore Hibernia oil field, discovered in 1979, 315 km (195 mi) southeast of St John's, Newfoundland, has estimated recoverable oil of 83 million m³ (525 million bbl) Sediments of the Hibernia oil field occur within the northeast trending Jeanne d'Arc rift basin (JDB), which records two rift phases, each followed by a period of post-rift thermal subsidence. Reservoir sands in the Hibernia oil field were deposited during the second intense episode of rifting between Callovian and Early Aptian times. -- The Hibernia Formation is Berriasian to Valanginian age and accommodates 85% of the recoverable oil in the Hibernia oil field. The formation is encountered within the average depth interval of 3,400 and 4,200 m. Sandstones of the Hibernia Formation were deposited in a fluvially-dominated deltaic complex and are composed of very fine- to coarse-grained, partially argillaceous quartzarenites and sublitharenites. Porosities (Φ) range between 4% and 24.2% and permeabilities (k) between 0.01 mD to 9860 mD. -- This study, of petrographic lithofacies, log character and response, and engineering data, evaluates Core Lab statistical analysis of porosity and permeability to define "hydraulic flow units" and Canadian Hunter's methodology of petrographic analysis to relate to flow units. Development of drainage character is a crucial process for maximizing hydrocarbon production. Permeability is a crucial parameter which defines the rate of fluid flow, and separate flow units in a reservoir. Permeability is highly variable as a complex function of petrophysical and depositional properties which must be identified on the scale of microscopic lithofacies and macroscopic facies associations. "Hydraulic flow units" of the Hibernia Formation reflect highly variable plug permeabilitv data Definition of flow units by means of k-Φ cross plots distinguish broad variations. -- Three general k-Φ clusters can be defined using k-Φ cross plots. A concept of "Enhanced Textural Maturity Index (ETMI)" relating sorting and roundness is developed. The ETMI shows strong correlation with permeability. "Reservoir Quality Zones (RQZ)" are defined based on facies analysis, SEM/EDS, thin section petrography, and k-Φ attributes. Anomalies contributing to a scattered data pattern are addressed. It is shown that facies architecture of the reservoir (i.e., the "mix" of lithofacies) is critical to effective interpretation. Integrated log suites and RQZ permit estimation of average horizontal permeability ranges in uncored sections when the availability of drill cuttings is restricted or non-existent. By using RQZ as a template in the Hibernia Formation a multi-parameter reservoir modelling and cell characterization in the model can be achieved. -- Individual depositional models have inherent k-Φ relationships. The assemblage models in the stratigraphic package and overprinting of diagenetic effects serve notice that neither geological nor engineering data can be left out of the equation if accurate characterization is to be expected.


identifier: Iams, William James <https://research.library.mun.ca/view/creator_az/Iams=3AWilliam_James=3A=3A.html>   (1977) A study of the bioerosion of coastal limestones: a photogrammetric approach.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: The present study investigates the importance of bio-erosion in the destruction of coastal limestones of the tropical island of Barbados. A stereophotogrammetric system capable of obtaining yearly photographs of the rock surface and of providing quantitative data on rock surface data points from which erosional values can be obtained is described. Results of photogrammetric analysis of five study localities show a range of erosion rates (for intertidal and supratidal localities) which vary from 1.2 mm./year to 2.4 mm./year. Following establishment of erosion rates for the localities studied, calculations have been carried out to determine the erosional capabilities of the epilithophagic organisms present on the rock surfaces. These calculations show that in no case do epilithophagic organisms account for more than 40 per cent of the total erosion. Other factors which may account for the remaining erosion include physical and chemical weathering as well as non-epilithophagic biological erosion. The author suggests that of the latter category the erosional effects of boring microphytes (chasmolithic and endolithic algae and fungi) are extremely important in explaining the non-epilithophagic erosion. These microphytes act directly on the substrate by biochemical boring activity and indirectly by attracting the epilithophagic organisms which rasp the rock to gain nourishment provided by the thalli of the microphytes.


identifier: Deveau, Stuart William <https://research.library.mun.ca/view/creator_az/Deveau=3AStuart_William=3A=3A.html>   (1992) A metamorphic, structural and geophysical investigation of the Mount Cormack subzone, Central Newfoundland.  Masters thesis, Memorial University of Newfoundland.

abstract: The Mount Cormack Subzone (MCSZ) is located in central Newfoundland and has been interpreted as a tectonic window which exposes rocks of the Gander Zone through the surrounding Dunnage Zone. Structural evidence suggests that three deformation events caused the present geologic pattern. The first deformation was a result of thrusting of an ophiolite on to the Spruce Brook Formation (SBF) causing recumbent isoclinal F₁ folds in the latter; subsequent tectonic shortening during the second deformation caused the formation of large- and small-scale sub-horizontal F₂ folds. Evidence of low-pressure, high-temperature metamorphism suggests that this phase of crustal shortening was followed by widespread crustal extension. This thinning of the crust was accompanied by crustal melting at depth causing high geothermal gradients in the SBF and the development of mineral reactions which have been recorded as reaction isograds. All earlier structures were refolded during the D₃ deformation which rotated the D₂ structures and the isograds and caused a broad doming. -- The mineralogy preserved in the metasedimentary rocks of the Mount Cormack Subzone indicates that the regional metamorphic grade increases from greenschist to upper amphibolite facies. The reaction isograds crosscut the large-scale second generation folds in the area consistent with early thrusting (emplacement of oceanic crust of Dunnage Zone over Gander Zone) and shortening, followed by structural and thermal doming. The attitude of the S₂ foliation within the terrane is approximately parallel to the edges of the MCSZ and dips away from the centre, consistent with a broad domal structure. -- Five reaction isograds have been mapped within the Mount Cormack Subzone as follows: 1) biotite-muscovite-chlorite isograd; 2) andalusite-biotite-muscovite isograd; 3) sillimanite-biotite-muscovite isograd; 4) sillimanite-K feldspar isograd; and 5) melting isograd defining the beginning of partial melting. Bulk rock compositions lie within the central part of the AFM diagram resulting in cordierite and staurolite being relatively rare. -- Mineral assemblages from both sides of the bathogradic reaction: -- biotite + garnet + andalusite + vapour ⇄ -- staurolite + muscovite + quartz + sillimanite occur in rocks of appropriate composition and temperature, indicating a pressure of approximately 3.2 kilobars at the bathograd. This bathograd is approximately coincident with the sillimanite-biotite-muscovite reaction isograd. Pressure increases slightly with increasing metamorphic grade (i.e. higher pressures occur on the high grade side of the isograd), consistent with interpretations that either the high-grade areas underwent greater post-metamorphic uplift or that the syn-metamorphic Through Hill Granite dragged up its metamorphic aureole during emplacement. -- Results of geothermobarometry from samples from the Mount Cormack terrane indicate that pressure estimates range from 2.5 - 3.5 kilobars and temperature estimates vary from 525 - 600 ﾟC for andalusite-biotite-garnet assemblages, and up to 650 ﾟC for sillimanite-biotite-garnet assemblages. These estimates indicate high geothermal gradients of up to 50 ﾟC/km in the high-grade assemblages. Such high geothermal gradients are consistent with the suggestion that crustal thinning played an important role in the metamorphic development of the Mount Cormack Terrrane. P-T vectors from zoned minerals from high-grade rocks are shallow, indicating that the amount of syn-metamorphic uplift and erosion was small. Exhumation must have been delayed until after substantial post-metamorphic cooling, and is not recorded in the mineral assemblages. -- Interpretation of gravity and magnetic anomalies in the Mount Cormack Subzone indicates a model for the subsurface geology that is consistent with that observed at the surface. Large magnetic and gravity anomalies are associated with the ophiolitic rocks, and there appears to be little effect from the other units in the study area. The 1985 gravity profile is asymmetric; the anomaly associated with the Coy Pond Complex is much smaller than that associated with the Pipestone Pond Complex, suggesting that the Partridgeberry Hills Granite (or similar low-density body) extends beneath this ophiolite. -- The magnetic low directly northwest of the Coy Pond Complex results from the fact that the dip of the ophiolite is similar to the inclination of the overall magnetic field. Small-scale magnetic anomalies within the Mount Cormack Subzone are interpreted as traces of bedding defined by cordierite-magnetite sub-assemblages. The attitude of these features is consistent with structural measurements made at the surface. The magnetic anomaly associated with the high-grade pelites may be due to the breakdown of hematite to form magnetite in the presence of reducing fluids.


identifier: Leslie, Ian <https://research.library.mun.ca/view/creator_az/Leslie=3AIan=3A=3A.html>   (1994) A comparison of the methods of the engineering seismic refraction analysis and generalized linear inversion for deriving statics and shallow bedrock velocities.  Masters thesis, Memorial University of Newfoundland.

abstract: Refracted first arrivals recorded in high resolution seismic surveys contain key information for deriving statics and are important for improving the resolution of reflections. They may also be useful for estimating shallow bedrock velocities as an aid to interpreting bedrock geology below the weathered layer. Two different techniques to estimate near-surface information are described in this thesis : one is a generalized linear inversion (GLI) technique that uses damped least squares to estimate statics and Occam's method to estimate lateral variations in the bedrock layer for interpretation of geology; the other employs the reciprocal method and the smoothing of forward and reverse apparent velocity profiles in the analysis. A comparison is made between the effectiveness of these techniques for a synthetic data set and 3 high resolution data sets collected at two mine sites in central Newfoundland for mining exploration purposes. -- For these data there was no discernible difference in the quality of the stacked seismic sections for the data sets processed with statics derived using GLI compared with the reciprocal method. Lateral variations in bedrock seismic velocity are resolved to the same degree by both direct smoothing and Occam's technique, resulting in similar geological interpretations. The resolution of the bedrock velocities in both methods depends on the acquisition parameters, the signal-to-noise ratio in the field, and the amount of smoothing applied to the data. Future work may be to use a more efficient numerical procedure in GLI to handle sparse matrices and to make a comparison of these techniques for the case of diving raypaths.


identifier: Sargent, Nicolas J. <https://research.library.mun.ca/view/creator_az/Sargent=3ANicolas_J=2E=3A=3A.html>   (1994) A hydrogeological and hydrogeochemical study of the evolution of ground water in a fractured granite, Holyrood Newfoundland.  Masters thesis, Memorial University of Newfoundland.

abstract: An extensive set of hydrogeological and geochemical data has been collected from a 150 m deep borehole in the near coastal discharge area of the Holyrood Granite, Newfoundland. Because of the selected location of the borehole, over the underlying saltwater wedge, it was possible to intersect flow paths that are believed to have extended considerably deeper within the aquifer than the depth of the borehole. -- The physical data indicate that the geometric average of the hydraulic conductivity over the length of the borehole is approximately 4 x 10⁻⁹ m/s and that the open fractures, controlling most of the flow in the aquifer are approximately vertical and parallel to the coast. Fractures of this nature have been postulated by others to have resulted from isostatic post glacial rebound. The hydraulic conductivity (measured at approximately 2 m intervals along the entire length of the borehole) shows a decrease of approximately three orders of magnitude with depth. Based on the hydraulic conductivity measurements made in the study borehole, known hydraulic gradients and probable flow-path length, it is believed that water samples collected may have had residence times of the order of 1000 a. -- Inspection of aqueous chemical data reveals that some parameters have a strong correlation with depth while other analytes have a strong inverse correlation with hydraulic conductivity. In general the water quality reflects the effect of low-temperature weathering of an alumino-silicate rich granite. However, the water samples collected were all relatively rich in chloride. Though there is no direct evidence of the source or sources of chloride in the study area, evidence from other granitic terrains indicate that the likely sources of chloride in the groundwater are from the rock mass (possibly from fluid inclusions) and from seawater. -- Study and analysis of fracture plane mineralogy using X-ray diffraction (XRD) and scanning electron microscopy (SEM) has provided evidence for a suite of minerals which may control the groundwater chemistry. Thermodynamic speciation calculations using the water analysis data indicates minerals including calcite, amorphous silica, kaolinite, and some varieties of feldspar may be precipitating. Subsequent mass balance modelling using the groundwater analyses could not identity a groundwater evolutionary scheme that was consistent with the speciation calculations unless both a seawater source of chloride and a rock source of chloride were invoked. However, the results indicated that the percentage of seawater mixed with the groundwater decreased with depth, while the fraction of chloride added from the hypothetical rock source increased with depth. This, together with the inverse correlation of dissolved silica with hydraulic conductivity, probably reflects the increasing importance of rock-water interaction with depth, in-turn reflecting increasing aquifer residence times at increasing depths. -- Oxygen and hydrogen isotope data collected during the study indicate that both isotope systems show a strong correlation with depth and both are increasingly enriched in their light isotopes with depth. The decrease in ¹⁸O and ²H abundance with depth is consistent with the expected differences in altitudes of recharge between the deepest groundwater samples collected (believed to have been recharged at approximately 170 m above sea level), and the shallowest groundwater samples collected (believed to have been recharged at 60 m above sea level). This evidence indicates that flow through the aquifer (although it occurs in discontinuous fractures) is, on a large scale, roughly equivalent to well ordered porous granular flow. -- The interpretation of the isotope data together with the results of mass balance modelling suggests an internally consistent evolutionary scenario. It is proposed that the modelled decline of the saltwater component with depth reflects the addition of  marine aerosols that provide chloride to recharging waters in quantities that decrease with increasing distance inland. -- The increase in the modelled rock-derived chloride source with depth is consistent with the increasing degree of low-temperature rock-water mass exchange with increasing depth, itself resulting from increased aquifer residence time with depth.


identifier: Chorlton, Lesley B. <https://research.library.mun.ca/view/creator_az/Chorlton=3ALesley_B=2E=3A=3A.html>   (1983) Geological development of the southern Long Range Mountains, southwest Newfoundland: a regional synthesis.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: The southern Long Range Mountains in southwest Newfoundland are traversed by a major, northeast-trending fault, the Cape Ray Fault. The fault zone is overlain by Emsian-Eifelian terrestrial sedimentary and bimodal volcanic rocks of the Windsor Point Group. Terranes juxtaposed along the fault began their development as an Early Paleozoic(?) ocean basin (Terrane I-NW) and an Ordovician arc volcano-plutonic and sedimentary basin complex at least partly resting on oceanic crust (Terrane II-SE). These terranes were rapidly converted to continental crust through thrusting, production of synkinematic granitoid rocks, and subsequent convergent wrenching (transpression). -- The Cape Ray Fault was formerly called a cryptic suture because pre-Windsor Point Group rocks along its northwest side were considered Grenvillian, and along its southeast side Hadrynian(?). The original criteria for calling the fault a cryptic suture are therefore incorrect (above). Nevertheless, the Cape Ray Fault is considered the most significant late tectonic boundary in the area. -- A low pressure granulite facies foliation predating regional deformation in the cumulate metagabbro (MOHO) layer of the oceanic crust northwest of the fault is interpreted tentatively as the result of rapid ocean floor spreading. Thrusting, involving all levels of the lithosphere from  depleted upper mantle to sedimentary and volcanic cover rocks, may have occurred before this cumulate sequence had substantially cooled. Voluminous tonalite was apparently produced and emplaced during thrusting. Thrust-stacked ophiolite and synkinematic granitoid rocks were later intruded by mafic to felsic plutons. -- The volcano-plutonic centre southeast of the fault contains a high proportion of dacitic and rhyolitic volcaniclastic rocks. After its maturation, recumbent folding tectonically buried distal parts of the volcanic sequence and the adjacent sedimentary basin. Amphibolite facies metamorphism and partial melting to produce voluminous tonalite-granodiorite followed, after which megacrystic monzogranites were emplaced. -- Timing considerations suggest that the thrusting in the northwest was an early Taconic event, and the recumbent folding in the southeast was a late Taconic event. -- Later 'transpression'-related deformation events were Acadian to Hercynian. They resulted in locally intense, penetrative deformation, the emplacement of leucogranites, the strike-slip, repetition of pre-Acadian sequences, fault-controlled deposition of sedimentary and volcanic rocks, and high angle reverse faulting.


identifier: Mengel, Flemming Cai <https://research.library.mun.ca/view/creator_az/Mengel=3AFlemming_Cai=3A=3A.html>   (1987) Thermotectonic evolution of the Proterozoic-Archaean boundary in the Saglek area, northern Labrador.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: In the Saglek Fiord area, northern Labrador, sediments of the Lower Proterozoic Ramah Group occur as a north-trending fold belt which overlies the boundary between the Nain Province to the east and the Churchill Province to the west. The Nain Province is a polycyclic Archaean gneiss complex, consisting of tonalitic to granodioritic gueisses with remnants of supracrustal sequences. The metamorphic grade varies from amphibolite to granulite facies. In the Saglek area, rocks in the Churchill Province are mainly Archaean gneisses thoroughly reworked in a major north-south oriented transcurrent sinistral shear zone. Three tectonically juxtaposed north-trending lithotectonic terranes can be distinguished in the Churchill Province (from east to west): the Amphibolite Facies Terrane (AFT), the Granulite Facies Terrane (GFT), and the Tasiuyak Terrane (TT). -- The sediments of the Ramah Group were deposited unconformably on the peneplained Archaean basement, as evidenced by a well preserved regolith and basal conglomerate. Subsequently, the Hudsonian Orogeny caused deformation and metamorphism of the Ramah Group. -- Two thermotectonic events of Proterozoic age can be distinguished in the Saglek area. Using Proterozoic dykes (2300-2400 Ma) as time markers, the structural evolution can be subdivided into "Early Proterozoic" and "Hudsonian" orogenic events. The Early Proterozoic orogeny is characterized by transcurrent shearing and counterclockwise rotation of structures into parallelism with the north-south oriented sinistral shear zone. Proterozoic dykes clearly demonstrate the rotation; these are east-west oriented in the Nain Province, and rotate towards a north-south orientation in the AFT and GFT. The GFT, TT and most of the AFT are located within the shear zone, and are characterized by well developed subhorizontal mineral lineations and steeply west-dipping planar (mylonitic) foliations. Rocks In the GFT and TT are in granulite facies, and are interpreted to correspond to the deeper levels of a major shear zone, while the AFT, in amphibolite facies, represents a higher level. The Ramah Group does not possess any structural overprints attributable to the transcurrent shearing, and deposition is thus believed to post-date Early Proterozoic thermotectonism. -- During the subsequent Hudsonian Orogeny, which is characterized by an east-west oriented compressive tectonic regime, east-directed thrusting caused a reversal of the metamorphic sequence established in the Early Proterozoic shear zone. Rocks of the GFT and TT were thrust eastwards over the AFT, which in turn was thrust over the Ramah Group causing deformation and metamorphism of the sedimentary sequence.  -- Petrographic and thermobarometric studies of Early Proterozoic mineral assemblages in the GFT and TT show that evidence of both peak metamorphic conditions and subsequent decompression reactions is preserved. Highest P and T (10 kbar and 800ﾟC) are recorded by cores of coexisting minerals in equigranular aggregates, whereas rims record varying degrees of post-peak re-equilibration. Substantial decompression accompanied by only minor cooling (10 to 5 kbar and 800 to 650ﾟC) is shown by symplectites developed at garnet rims and between garnets and clinopyroxenes. These symplectites developed during erosion and uplift immediately following the Early Proterozoic tectonothermal event. -- Hudsonian metamorphic effects are restricted to the rocks of the Ramah Group and to minor retrogression of assemblages in the AFT. Microstructural evidence suggests that the metamorphic parageneses observed in the Ramah Group formed during a single metamorphic event. Hence the variations along the present erosional level represent a "metamorphic field gradient". Metamorphic grade in the Ramah Group increases from east to west and from north to south; the highest grade is recorded south of Saglek Fiord and corresponds to ca. 650°C/6.5 kbar. -- Key words: Labrador; Saglek area; Archaean-Proterozoic boundary; Early Proterozoic transcurrent shear zone; Hudsonian Orogeny; granulite facies; amphibolite facies; geothermometry; geobarometry; decompression reactions; symplectites; Ramah Group.


identifier: Stenzel, Sheila Rae <https://research.library.mun.ca/view/creator_az/Stenzel=3ASheila_Rae=3A=3A.html>   (1991) Carbonate sedimentation in an evolving Middle Ordovician foreland basin, western Newfoundland.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: Table Head and Goose Tickle group strata in western Newfoundland are a deepening-upward, carbonate to clastic sequence deposited on the convergent, paleosouth-facing, North American continental margin during Middle Ordovician time. Preceding passive margin platform growth was abruptly terminated by widespread, early Middle Ordovician block-faulting and differential uplift (St. George Unconformity) caused by migration of a peripheral bulge across the platform interior. Subsequent sea level rise led to widespread peritidal, then shallow subtidal, carbonate deposition (Table Point Formation) on a tectonically unstable platform that formed the western flank of the evolving Taconic foreland basin. Synsedimentary faulting and differential subsidence profoundly influenced sedimentation, leading to marked variations in thickness and abrupt lateral and vertical changes in platformal carbonate lithofacies. Episodic seismicity and changes in slope triggered gravitational slides and flows. This platform was in turn tectonically drowned by extensional faulting and differential collapse as it became part of the outer trench slope of the subduction zone. Thin-bedded, hemipelagic and turbiditic limestone and shale (Table Cove Formation) accumulated on discontinuous, gently-dipping carbonate slopes and basin margins of variable duration and facing direction. Massive, polymictic, carbonate debris flow conglomerate, calciturbidite and shale (Cape Cormorant Formation) were deposited in an isolated basin adjacent to a high relief fault scarp that exhumed several hundred metres of buried, older, passive margin platformal carbonate. Laminated black shale (Black Cove Formation) accumulated in remote, sediment-starved basins, and on the tops of isolated, rapidly foundered, relict platforms. As the (collapsed) platform entered the trench it was buried by siliciclastic flysch (American Tickle Formation and Mainland Sandstone) derived from an advancing accretionary prism. Terrigenous mud, silt and sand, transported mostly by turbidity currents travelling southwest parallel to the trench axis, accumulated in topographic depressions controlled by antecedent structural domains. Contemporaneous reverse faulting generated new escarpments in the trench, sourcing limestone debris flow conglomerates and calciturbidites deposited in intra-trench depressions (Daniel's Harbour Member).


identifier: Worsfold, Richard D. <https://research.library.mun.ca/view/creator_az/Worsfold=3ARichard_D=2E=3A=3A.html>   (1981) Surface and airborne infrared detection of sea ice hazards.  Masters thesis, Memorial University of Newfoundland.

abstract: This Masters Report is concerned with the assessment of the capability of instruments to detect ice hazard targets using the infrared portion of the electromagnetic spectrum. It is a target/sensor interaction study and discusses infrared theory, atmospherics, basic infrared systems and the targets being sensed. These factors are assessed to determine optimum infrared capability. -- The results of this target/sensor interaction study shows that the temperature ranges to be sensed for sky, marine and targets are basically ambient temperature (-20° to 20°C). Wavelengths for sensing are identified as the 3 to 5 micrometer and 8 to 14 micrometer ranges with a peak wavelength of 10.6 micrometers identified as the optimum for sensing the temperature range -20° to 20°C. -- The report shows that the potential exists to use infrared systems and devices to detect and monitor icebergs and sea ice but before conclusive detection can be achieved the ice targets such as icebergs, bergy bits, growlers, multi-year floes and first year floes must be characterized according to their infrared signature. The lack of characteristic infrared target signatures is the weakest link in assessing the capability of any infrared sensor for ice detection. A target signature program is recommended for both wavelength ranges discussed, the 3 to 5 micrometer and the 8 to 14 micrometer.


identifier: Yang, Dan <https://research.library.mun.ca/view/creator_az/Yang=3ADan=3A=3A.html>   (1992) Dynamic properties of Beaufort Sea soils.  Masters thesis, Memorial University of Newfoundland.

abstract: A study of the deformation behavior of marine soil subjected to long term cyclic loading is presented in this thesis. The study includes both experimental data and analytical predictions. Constitutive relationships relevant to time-dependent deformation behavior of marine cohesive soil under long term cyclic loading are derived based on a number of classic rheological models. The experimental method for determining the creep function is described. Long term cyclic loading tests were conducted on a load-controlled cyclic triaxial system. The theoretical predictions of the deformations are presented and compared to laboratory results. The potential applications of each rheological model to marine geotechnical engineering are discussed. -- This thesis also presents the results of an investigation performed to study the liquefaction potential or cyclic strength of four soils from the Beaufort Sea and one from Newfoundland. Results from the different soils are compared under different drainage conditions and overconsolidation ratios. The effects of cyclic stress ratio, dilatancy and mean particle size were also studied and are presented. The stress-strain relationships of the soils are demonstrated and discussed. -- An understanding of the stability threshold and dynamic stiffness behavior of marine soils under cyclic loading is required in the dynamic analysis of offshore structures subjected to earthquake excitation or storm wave action. Therefore, the third objective of this experimental investigation was to quantify the stability threshold and dynamic modulus for saturated Beaufort Sea soils under different over-consolidation ratios. The laboratory experiments were conducted on a load-controlled cyclic triaxial system.


identifier: Johnston, Dennis Hugh <https://research.library.mun.ca/view/creator_az/Johnston=3ADennis_Hugh=3A=3A.html>   (1992) The Noggin Cove formation and Carmanville melange: island arc rifting in northeast Newfoundland.  Masters thesis, Memorial University of Newfoundland.

abstract: The Noggin Cove Formation consists mainly of fragmental mafic volcanic rocks with subordinate pillowed basalt and black shale. Massive volcanic conglomerates and coarse sandstones, with lesser amounts of medium-bedded tuffs and lapilli breccias, dominate the fragmental rocks. Volcanic conglomerates and coarse-grained sandstones were predominantly deposited as subaqueous debris flows, some of which are spectacular in terms of their thickness and clast size. -- The volume of fragmental rocks relative to basaltic lavas indicates an explosive volcanic source; ubiquitous vesicular clasts indicate shallow marine to subareal eruption. Debris flow conglomerates and sandstones dominate southern exposures but in the north they are subordinate to basaltic lavas and shallow marine deposits (highly calcareous tuffs and breccias). This distribution implies fragmental rocks were transported southward to form a marine volcaniclastic apron over pillow lavas, lava flows and basaltic dykes. -- The Carmanville Melange consists mainly of sandstone, siltstone and mafic volcanic clasts and blocks in a black shale matrix. Melange is interbedded and interfolded with volcanic rocks of the underlying Noggin Cove Formation and with siltstones and sandstones of the overlying Woody Island Siltstone. In many cases, folded beds of siltstone can be seen within the black shale matrix. The melange is interpreted as olistostromal. -- The Noggin Cove Formation and Carmanville Melange have undergone at least three stages of folding. D₂ deformation is the most intense, resulting in a very strong northeast trending cleavage which is axial planar to tight to isoclinal folds. Microprobe, SEM and textural analyses show that greenschist facies metamorphism and subsequent contact metamorphism have extensively altered the volcanic rocks of the Noggin Cove Formation. -- Rifting is indicated by the debris flows of the Noggin Cove Formation and by olistostromes of the Carmanville Melange and Woody Island Siltstone. An arc to back-arc geochemical transition matches the stratigraphic record of rifting. The arc to back-arc succession is correlated with the Exploits and Wild Bight groups of the western Exploits Subzone.


identifier: Van Nostrand, Timothy Stuart <https://research.library.mun.ca/view/creator_az/Van_Nostrand=3ATimothy_Stuart=3A=3A.html>   (1987) Geothermometry-geobarometry and ⁴⁰Ar/³⁹Ar incremental release dating in the Sandwich Bay area, Grenville province, eastern Labrador.  Masters thesis, Memorial University of Newfoundland.

abstract: Three major lithotectonic units have recently been defined in the Grenville Province of eastern Labrador on the basis of contrasting lithologic associations, structural style and metamorphic grade. Two of these units, the Groswater Bay and Lake Melville Terranes are interpreted to represent parts of the parautochthonous and allochthonous units, respectively, which are two regional subdivisions of the Grenvllle Province in Labrador. -- Geothermometry and geobarometry estimates derived from garnet - biotite - plagloclase - Al₂SiO₅ - quartz and garnet - orthopyroxene - clinopyroxene - plagioclase - quartz equilibria of selected paragneiss and mafic lithologies in the Sandwich Bay area suggest contrasting metamorphic P-T conditions of the two terranes. Estimates determined from the Groswater Bay Terrane range from 615°C to 850°C and 10 - 12 kbar, suggesting derivation from depths on the order of 30 to 40 km. In contrast estimates from the Lake Melville Terrane range from 650°C to 900°C and 6 - 10 kbar implying crustal derivation from 20 to 30 km. Microstructural relationships and mineral chemistry of the assemblages in each terrane suggest that the P-T estimates obtained from each terrane are representative of Grenvillian metamorphic conditions. -- Equilibrium P-T paths constructed from the geothermobarometry estimates are interpreted to represent a portion of the uplift trajectory for both the Groswater Bay and Lake Melville Terranes. These paths suggest that both terranes followed a near isothermal uplift path, implying rapid decompression during cooling. -- ⁴⁰Ar/³⁹Ar incremental release radiometric dating of hornblende concentrates from orthogneiss and associated mafic dikes from the study area reveal contrasting ages from both terranes. Age spectra from the Groswater Bay Terrane are generally discordant and are interpreted to result from a combination of the presence of excess argon components and partial gas loss as a result of thermal resetting of the argon system. One sample from the Groswater Bay Terrane yields a reasonably defined plateau age of 1260 +/- 5 Ma. A similar plateau age of 1241 +/- 3 Ma is obtained from a sample immediately south of the Rigolet thrust zone in the Lake Melville Terrane. The significance of these pre-Grenvillian ages is at present not understood since they do not correlate with any major event (thermal or cooling) previously known in the Grenville Province. However, they are tentatively interpreted to date a closure of argon in hornblende at ca. 1250 Ma. Spectra obtained from samples from the southern Lake Melville Terrane record reasonably well defined ⁴⁰Ar/³⁹Ar plateaux. One sample yields a plateau age of 1070 +/- 50 Ma, which is in broad agreement with the 1030 Ma age suggested for the culmination of Grenvillian metamorphism in the Lake Melville Terrane and is thus interpreted to represent the very rapid uplift following Grenvillian thermal overprinting. The most southerly samples yield younger ages of 1020 +/- 8 Ma and 980 Ma +/- 12 Ma and are interpreted to results from slower post-Grenvillian uplift and subsequent cooling through the retention temperature required for argon in the hornblende crystal lattice.


identifier: Haardeng-Pedersen, Gary Peter <https://research.library.mun.ca/view/creator_az/Haardeng-Pedersen=3AGary_Peter=3A=3A.html>   (1975) Studies on the dynamics of the rotating Earth.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: The spectrum of the geographic motion of the Earth’s rotation poled and confidence limits on this estimation of the spectrum are obtained in the first part of this thesis. These statistical tests negate the evidence for multiple peaks in the Chandler region and conclude that the Chandler excitation may be a non-stationary process. -- The response of the Earth to an external harmonic potential of second of third degree is presented in the second part of this thesis. An Earth model with a sub-adiabatic fluid core is considered for the second degree excitation and Love numbers are calculated; these give evidence of free oscillations called undertones. As the direct effects of rotation have been fully retained in this study, it is shown that the rotational couplings excite torsional modes and other spheroidal modes of oscillation.  Love numbers for the terdiurnal tide (M₃) are calculated for Earth models with both adiabatic and sub-adiabatic fluid cores.


identifier: Botsford, Jack W. <https://research.library.mun.ca/view/creator_az/Botsford=3AJack_W=2E=3A=3A.html>   (1987) Depositional history of middle Cambrian to lower Ordovician deep water sediments, Bay of Islands, western Newfoundland.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: The Northern Head group is an upper Middle Cambrian to Lower Ordovician base-of-slope sediment apron, deposited downslope from a shallow-water carbonate platform, and now disposed in imbricate thrust slices within the Humber Arm Allochthon, western Newfoundland. The group encompasses the upper Middle Cambrian to upper Tremadoc Cooks Brook Formation and the upper Tremadoc to middle Arenig Middle Arm Point Formation. The discovery of numerous fossil localities has facilitated the erection of a stratigraphic framework, embodying several correlatable members. These subdivisions reflect a natural change in the depositional style upward, from carbonate to shale-dominated. -- The Cooks Brook is characterized by abundant platform-derived, gravity-transported carbonate, and hemipelagic black shale, deposited in a deep water, poorly-oxygenated environment. Earliest sediments accumulated at the mouths of submarine canyons but were buried by debris flow conglomerate sheets and carbonate sand turbidites from an active, upslope shallow-water platform margin. -- Gravity transport of carbonate sharply diminished in earliest Ordovician time but hemipelagic carbonate sedimentation persisted into late Tremadoc time. -- The change to shale-dominated sediments of the Middle Arm Point reflects a new, low-relief margin upslope. Hemipelagic shale was accompanied by detrital, windblown dolomite and both were reworked by bottom currents. Diminished input of shelf and slope-derived organic carbon, and more vigorous marine circulation, resulted in elevated Eh levels in the depositional environment which are indicated by (1) a pronounced increase in bioturbation, and (2) a new "suboxic" diagenetic regime, distinguished by widespread precipitation of Mn-carbonate and barite, largely within the stability field of hematite. Condensed sedimentation characterizes the middle of the Middle Arm Point, spanning the Tremadoc/Arenig boundary. Shale deposition continued until the collapsing margin was buried by sandstones of the overlying Eagle Island formation during middle Arenig time. -- The Northern Head group and contemporaneous Cow Head Group were both part of an active carbonate margin until the Tremadoc. Their depositional and paleoceanographic histories diverged in late Tremadoc time, when a low-relief margin developed upslope from the Northern Head group while active carbonate sedimentation continued upslope from the Cow Head Group. This irregular carbonate margin morphology is suggestive of a basement-related structural juncture separating the two areas.


identifier: Pal, Badal Kanti <https://research.library.mun.ca/view/creator_az/Pal=3ABadal_Kanti=3A=3A.html>   (1992) Wave induced ocean diffusion.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

title: Wave induced ocean diffusion

abstract: Please see thesis for abstract.


identifier: Mackay, Robert I. <https://research.library.mun.ca/view/creator_az/Mackay=3ARobert_I=2E=3A=3A.html>   (1995) Low-temperature demagnetization of natural remanent magnetization in dolerites of a Proterozoic dyke swarm near Nain, Labrador.  Masters thesis, Memorial University of Newfoundland.

abstract: Dolerite dykes are presently considered to be the most important recorders of Precambrian paleomagnetism. This is because they can often be accurately dated (using U-Pb in baddeleyite) and can often be shown to carry primary remanence (using the baked contact test). However the mechanisms by which this stable natural remanence is retained over geological time is not well understood. In this thesis, observation of changes in remanence on cooling to 100 K in zero magnetic field and warming back to room temperature is used to help understand these mechanisms. -- Twelve specimens were studied from different dykes in a Proterozoic dolerite dyke swarm (U-Pb date of 1,277±3 Ma) located near Nain, Labrador. Each specimen carried a stable westerly-directed remanence that was likely acquired soon after crystallization. Alternating-field demagnetization curves of the natural remanent magnetization (NRM) of each specimen had a quadratic shape. The median destructive field (MDF), which is the alternating field required to reduce intensity by half, ranged from 18mT to 47.5mT for NRM. These properties suggest that remanence is carried by single-domain (SD) or pseudo-single-domain (PSD) grains of magnetite rather than by large multidomain (MD) grains. Median destructive fields were similar for anhysteretic remanent magnetization (ARM) and NRM but were smaller for saturation isothermal remanent magnetization (SIRM). -- Apparatus was built to measure remanence intensity as a function of temperature in cooling cycles to near liquid nitrogen temperature. Low-temperature demagnetization experiments were done for NRM, ARM and SIRM for all specimens. For the three specimens with highest median destructive fields (~40mT for NRM) low temperature cycling had relatively little effect on remanence as expected if the remanence was controlled by shape anisotropy. Similar low-temperature behaviour was reported by others for synthetic magnetites of less than .31μm grain size. -- The rest of the specimens showed a pronounced decrease in intensity of remanence on cooling in zero field. The rate of remanence decrease was greatest on approaching 120 K, the temperature of magnetite's Verwey transition from cubic to monoclinic crystal structure. Cooling below the Verwey transition resulted in little further decrease in remanence. On warming back to room temperature remanence increased once the Verwey transition was passed. The final remanence intensity after a cycle of cooling and warming as a function of the initial intensity is termed "recovery" and averaged about ~0.75 of initial remanence for NRM and ARM and ~0.60 for SIRM. The decrease of ARM on cooling from room temperature to near 120 K is shown to roughly parallel the decrease of saturation magnetostriction, suggesting that remanence decrease is due to unpinning of magnetoelastically controlled domain walls. -- Finally, combining our measurements of recovery in magnetite after low temperature cycling with measurements of others revealed that the higher the median destructive field of the specimen, the higher the recovery. This may be due to both median destructive field and recovery increasing with dislocation density.


identifier: Ritcey, David Henry <https://research.library.mun.ca/view/creator_az/Ritcey=3ADavid_Henry=3A=3A.html>   (1993) Geology, U-Pb geochronology and stable isotope geochemistry of the Hammer Down Gold Prospect, Green Bay District, Newfoundland.  Masters thesis, Memorial University of Newfoundland.

abstract: The Hammer Down gold prospect is an important example of the numerous mesothermal gold occurrences associated with structural zones of regional extent in the Newfoundland Dunnage Zone. -- The main mineralized zones in the Hammer Down prospect consist of structurally controlled quartz veins with abundant pyrite, chalcopyrite, and sphalerite, hosted by volcanic and sedimentary rocks of the Ordovician (Arenig) Catchers Pond Group, and by Early Silurian felsic porphyry dykes. Gold-bearing veins postdate sub- greenschist metamorphism and an early phase of deformation, and were produced synchronously with a locally intense S₂ fabric related to folding. Veins were preferentially emplaced in narrow brittle-ductile high strain zones within and adjacent to felsic dykes. The gold-bearing veins and Sj fabric are locally folded, and mineralized zones are truncated by a late brittle fault. Barren, paragenetically late veins, characterized by fluorite and low contents of sulphide minerals, are abundant in and near the gold-bearing zones. -- Gold is present within pyrite and along sulphide grain boundaries in veins and in locally sericitized, carbonatized, and pyritized wall rock. Hydrothermal alteration adjacent to veins is restricted to narrow zones, or is absent. Alteration of mafic rocks is characterized by muscovite, calcite, pyrite, quartz, and rutile, and is marked by enrichment in the lithophile elements K and Rb, and by sporadically elevated levels of Cu, Zn, and S. -- Felsic tuff from the Hammer Down prospect has an igneous U-Pb zircon age of 480 + 4/-3 Ma, and records arc volcanism in the Dunnage Zone. Felsic dykes from the prospect, which have a strong spatial association with gold, are petrographically and chemically distinct from the nearby King's Point volcanic-plutonic complex, but they are correlative with the Burlington Granodiorite, a regional plutonic unit of the eastern Baie Verte Peninsula. Zircon from a felsic dyke cut by a gold-bearing vein has a high degree of Proterozoic inheritance. Acicular zircon grains from this dyke have a ²⁰⁷Pb/²⁰⁶Pb age of 437 +/-3 Ma, which is considered the age of intrusion, and is a maximum age limit for gold deposition. -- Isotopic compositions of quartz (δ¹⁸O = 11.4±0.7) and calcite and ferroan dolomite from gold-bearing veins (δ¹³C = -6.2±0.7) are typical of mesothermal vein systems elsewhere. Oxygen isotope thermometry using quartz, chlorite, and muscovite indicates mineralization temperatures between 240 and 320°C. The ore- forming solutions had calculated δ¹⁸O values between 2.2 and 5.2 %o and δD values between -27 and -42 0/00, which are compatible with a predominantly metamorphic source having some meteoric contribution. Age constraints and regional considerations place the gold mineralizing event wthin a period of crustal extension and widespread magmatism that were part of an important Silurian orogenic phase in central Newfoundland. A meteoric component in the vein fluid system is atuibuted to the extensional setting, which promoted influx of surface water to deeper reservoirs.


identifier: Ramsey, R. Douglas <https://research.library.mun.ca/view/creator_az/Ramsey=3AR=2E_Douglas=3A=3A.html>   (1993) Land competition issues affecting agriculture in Newfoundland and Labrador.  Masters thesis, Memorial University of Newfoundland.

abstract: This thesis examines one particular constraint faced by agriculture: the implications of land competition and the resulting land use conflicts. This is done by identifying and describing land competition issues at two scales: a provincial overview and a detailed case study of one agricultural region in the Province, the Lethbridge-Musgravetovm Agricultural Development Area (LMADA). The issues were identified through questionnaires completed by professionals in the Agriculture Branch of the Department of Forestry and Agriculture (provincial overview) and to the farmers in the LMADA (case study). These issues were then clarified and reinforced with key informant interviews with resource users and agencies identified as competing for land with agriculture. -- Following this examination, two main policy options are described. These options are drawn from the existing literature, including experiences in Newfoundland and Labrador. The first option is for the implementation of farmland preservation policies, including restrictive zoning, differential taxation. Purchase of Development Rights (PDRs), and "Right-to-Farm" Legislation. The second option is for a policy of Integrated Resource Planning (IRP), also known as Integrated Resource Management (IRM). These options are presented with reference to both the existing literature, examples of such policies in other jurisdictions throughout North America, and information obtained in the questionnaires and key informant interviews.


identifier: Sung, Gee-Woong <https://research.library.mun.ca/view/creator_az/Sung=3AGee-Woong=3A=3A.html>   (1992) Geology and metamorphic evolution of the Indian Head Range, a Grenvillian inlier in West Newfoundland.  Masters thesis, Memorial University of Newfoundland.

abstract: The Indian Head Range (IHR), which forms an inlier in the western foreland of the Appalachian orogeny in Newfoundland, is mainly underlain by an upper amphibolite facies to granulite facies metaplutonic complex. Granulite facies units have annealed, high strain fabrics and include metanorthosite, meta-lherzolite, metagabbro and noritic, dioritic, granitic and politic gneiss. They predate a less deformed, amphibolite facies, foliated hornblende granodiorite. -- The IHR shows two distinct sets of ductile deformation fabric : (1) a relatively high strain group comprising gneissic to migmatitic rocks; and (2) a relatively lower strain group comprising foliated granitoids. This grouping is compatible with a subdivision made on the basis of grade of metamorphism, with the higher strain group possessing granulite facies assemblage and the lower strain group being characterized by amphibolite facies assemblages. Considering the relative ages of the units, it appears that two metamorphic events occurred in the IHR. -- Rare aluminous-magnesian mineral assemblages, indicated by the phases sapphirine and kornerupine, occur in the politic gneiss, which forms km-scale inclusions in metagabbro and screens between metagabbro and other gneissic plutonites. -- Assemblages in the politic gneiss are subdivided into three groups. (1) Quartz-bearing assemblages consist of qtz-opx-crd-sil-bio-pla-ilm/mt ± spl ± krn ± gnt ± gdr ± (crn). Sapphirine-bearing assemblages are subdivided into an Al-rich assemblage (2) spr-krn-opx-crd-sil-bio-pla-ilm/mt ± spl ± rt, and al Al-poor assemblage (3) spr-opx-bio-pla-ilm/mt ± spl ± rt. The sub-assemblage spr-qtz has not been observed. Reaction textures suggest the following metamorphic history. In quartz-bearing rocks, an early crd-spl-high Al opx (8.5-9.5 wt% Al₂O₃) assemblage implies T ≈ 800°C and P ≈ 8-10 kbars. In quartz-free rocks, the reaction crd-spl = spr=opx took place under similar P-T conditions. Kornerupine replacement by the reaction krn = spr-crd-low Al opx (5-7 wt% Al₂O₃) implies much lower pressures (5-6 kbars) at similar T (750 - 800°C), indicating a quasi-isothermal synmetamorphic decompression event from 8-10 to 5-6 kbars.  [Please see thesis for remainder of abstract.]


identifier: Mackenzie, Leonard M. <https://research.library.mun.ca/view/creator_az/Mackenzie=3ALeonard_M=2E=3A=3A.html>   (1991) Geology, geochemistry and metallogeny of the Burnt Lake area, central mineral belt, Labrador, Canada.  Masters thesis, Memorial University of Newfoundland.

abstract: The Burnt Lake area, located within the central region of the Central Mineral Belt of Labrador, is underlain by the Early Proterozoic (1855 Ma) supracrustal sequence of the Upper Aillik Group felsic volcanic and associated sedimentary rocks. Intruded into this volcanic pile is the 1650 Ma Burnt Lake Granite, a high level, leucocratic, post-tectonic granite. -- The area was the focus of uranium exploration in the late 1970's and hosts open pit reserves of 140,000 tonnes grading 0.082% U₃O₈. -- Uranium was originally deposited (1855 Ma) by subvolcanic leaching of volcanic glasses and concentration during K- metasomatic alteration of the felsic volcanic rocks (Burnt Lake Potassic Showing) and later upgraded during a period of magmatic and metamorphic activity between 1800 Ma - 1740 Ma (Burnt Lake Sodic, Emben amd Aurora River Showings). This produced uranium enrichments associated with intense Na- metasomatism and is characterized as epigenetic-hydrothermal. -- Base metal (and possibly some uranium) mineralization was later superimposed on the Burnt Lake uraniferous occurrences which originated as magmatic fluids from the Burnt Lake Granite (1650 Ma). The mineraliza-tion is characterized as epigenetic magmatic-hydrothermal (granophile) with potassium, lead, zinc, copper, fluorite and molybdenite enrichments. -- Model ages from a galena separate from Burnt Lake, hosted in felsic volcanic rocks of the Upper Aillik Group (1355 Ma) are 1651 Ma for the lower crust-type reservoir. This indicates an age of 1651 Ma for at least some of the lead mineralization derived from a magmatic source. --  An Rb/Sr isocron for the Burnt Lake Granite has produced an age of 1651 ± 140 Ma, however, the isotopic signature has been disturbed by fluid effects and a partial re-setting of the isotopic clock during the Grenville Orogeny. -- Significant concentrations of molybdenite occur near the contact of the Burnt Lake Granite and the meta-felsic volcanic rocks. Differentiation trends in geochemical data for this granite indicate vapour phase concentration towards the top of the pluton.


identifier: Quinn, Louise Anne <https://research.library.mun.ca/view/creator_az/Quinn=3ALouise_Anne=3A=3A.html>   (1992) Foreland and trench slope basin sandstones of the Goose Tickle Group and Lower Head Formation, western Newfoundland.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: Two major Ordovician siliciclastic units can be recognised in western Newfoundland: the parautochthonous Goose Tickle group (Llanvint - ?Llandeiloi, and the allochthonous Lower Head Formation (Arenig - Llanvirn). This study has resulted in the distinction cf two uniu; within the Goose Tickle group: the American Tickle and Mainland formations. The Howe Harbour member has also been newly recognised w ith.tin the American Tickle formation. -- All three formations are dominated by turbidites, ranging from the deposits of low and moderate concentration flows for the relatively sand-poor American Tickle formation, to high concentration flows for the sand-rich Mainland and Lower Head formations. The American Tickle formation was deposited under anoxic conditions in a foreland basin with at least two different sediment input points. The turbidites and debris flows of the Howe Harbour member were locally shed in front of faults generated by allochthons (Taconic Allochthons) which were advancing over the eastern margin of the basin. The Mainland formation was deposited in the southern part of the same basin, but in much closer proximity to a third sediment input point, and has complex characteristics related to unusual local topography. The Lower Head Formation exhibits complex facies variations and was deposited in a confining trench slope basin or basins. -- Although all three units are petrographically similar, the Lower Head Formation is distinct in that it contains a higher feldspar content and a lower lithic fragment content than the Goose Tickle group. Petrographic characteristics are consistent with mixed sources for all units. While many of the sources can be related to lithologies now present in the Taconic Allochthons, there is no lithology in the allochthons which can be related to felsic volcanic grains and rounded microclines. Mixing of detrinis in a now destroyed basin or basins is implied, and the overall provenance suggests supply of sediment from a major and complex area of uplift of which the Taconic Allochthons are only a small and incomplete remnant. This uplifted area included passive margin sediments, possibly Grenville basement and a major arc terrane which may have been compressed prior to erosion. -- Geochemical analyses also indicate mixed sources and demonstrate that the Lower Head Formation is distinct from the Goose Tickle group. Comparison of the behaviour of trace elements between the units suggests that weathering of source areas may have been more intense during the Llanvirn than the Arenig. -- Although western Newfoundland foreland and trench slope sediments are broadly typical of their tectonic setting, variations in sedimentology do exist along the length of the system, and they differ in subtle respects from analogous units in Quebec, supporting the concept of variations in tectonic style along the length of the Appalachian basin.


identifier: Lee, Christopher Bernard <https://research.library.mun.ca/view/creator_az/Lee=3AChristopher_Bernard=3A=3A.html>   (1994) Polykinematic evolution of the Teakettle and Carmanville Melanges in the exploits subzone, Northeast Newfoundland.  Masters thesis, Memorial University of Newfoundland.

abstract: The Carmanville Melange contains an impressive variety of sedimentary, igneous and metamorphic blocks in a silty shale matrix. Block lithologies include: pillowed basalts, gabbro, trondhjemite, greywacke, grey siltstone, rhythmically bedded grey siltstone and black shale, and polyphase deformed metamorphic rock. The polydeformed and metamorphosed rocks consist of variably strained pillow basalts, banded mafic metavolcanic rocks, and psammite, in a black pelitic matrix. This assemblage is interpreted as an earlier generation of melange (Teakettle melange), that now occurs as discrete blocks in the Carmanville Melange. -- The Carmanville Melange is associated with distinctive coticule-bearing shales and siltstones of the Woody Island formation and fragmental volcanic rocks of the Noggin Cove Formation. All of these units are assigned to the Hamilton Sound complex, and distinguished from the adjacent Davidsville Group. -- Structural and metamorphic contrasts between the Teakettle and Carmanville melanges are spectacular. Teakettle psammites locally exhibit overprinting of three phases of deformation, at least two with associated fabric development. The strong asymmetry of most of the structures, coupled with large scale boudinage, suggests a tectonic origin for the Teakettle melange or extreme deformation of an existing melange, at mid to deep crustal levels. -- The Carmanville Melange formed at higher crustal levels. It has early, asymmetrical layer-parallel shearing, produced by independent particulate flow, and asymmetrical, isoclinal folding in entrained stratified blocks. Later structures record increasing viscosity during deformation, progressing from folds and shear bands, to shearing on discrete surfaces and finally brecciation and cataclasis. Structures in the Carmanville Melange are interpreted as products of diapiric processes whereby a mobile matrix sampled and entrained of a wide variety of lithologies, with dramatic structural and metamorphic contrasts. The Carmanville Melange is therefore a non-stratigraphic unit, that has injected the Noggin Cove and Woody Island formations, and post-dates both. Diapiric mobility could have been driven by thrust imbrication, with attendant overthickening and overpressuring of wet sediments, at the base of an accretionary wedge.


identifier: Myrow, Paul Michael <https://research.library.mun.ca/view/creator_az/Myrow=3APaul_Michael=3A=3A.html>   (1987) Sedimentology and depositional history of the Chapel Island Formation (late Precambrian to early Cambrian), southeast Newfoundland.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: The Chapel Island Formation, a 1000 m thick shelf sequence of late Precambrian-Early Cambrian age, is receiving considerable attention as a leading candidate for the boundary stratotype for the Precambrian-Cambrian boundary. The formation, composed of five informally defined members, has been divided into six facies associations (1-6). -- Facies Association 1 consists of red and green sandstones and shales (Facies 1.1/1.2), and grey to black, thinly laminated shales and silty shales (Facies 1.3), deposited in tidally-influenced peritidal and semi-restricted shoreline environments, respectively. -- Facies Association 2 consists of very thin to medium bedded sandstones and siltstones (Facies 2.1/2.2) with subordinate green and red laminated siltstones (Facies 2.3/2/4), deposited within a muddy deltaic system. Storm-generated sandstones (tempestites), and other storm-related features (e.g., gutter and pot casts), dominate Facies 2.1 and 2.2. These facies are also characterized by abundant and diverse slide and gravity-flow features (debrites, turbidites, and liquefied flow deposits) formed under conditions of high sediment supply in a delta front/upper prodelta setting. Thin bedded and laminated siltstones of Facies 2.3/2.4 form excellent marker horizons and represent delta abandonment facies. -- Laminated green siltstones of Facies Association 3 are considered outer shelf deposits. Sandstone laminae are interpreted as distal tempestites deposited by waning flows below storm wave base. -- Facies Association 4 consists of red, green and gray mudstones of inner shelf origin and thing fossiliferous algal limestones deposited in peritidal environments. Deposition took place on a low energy, oxygen-stratified muddy shelf, with the limestone beds forming during low stands of sea level. -- Facies Associations 5 and 6 were deposited on a storm- and wave-dominated shelf below and above the influence of storm waves, respectively. The thin to medium bedded sandstones and siltstones of Facies Association 5 represent distal tempestites. The planar laminated and hummocky/swaly cross-stratified sandstones of Facies Association 6 represent inner shelf and shoreface environments. -- The depositional history of the Chapel Island Formation records a shift from tectonically-active fault-bounded basins (underlying Rencontre Formation) to a tectonically-stable platform (overlying Random formation). Three distinct phases of sedimentation have been delineated. Phase 1, corresponding to the lower part of the formation (members 1-3), is a period of relative sea level rise recording a shift from marginal marine environments to delta front;/prodelta settings to the outer shelf. Phase 2, represented by members 3 and 4, is interpreted as a time of dropping relative sea level and low sediment input. Small scale relative sea level changes are recorded by variations in color, sedimentary and biogenic structures, diagenetic features and the deposition of thin peritidal limestone beds. Phase 3 (member 5) is a period of rapid deepening followed by shallowing with the progradation of a storm- and wave-dominated shelf. This phase, recording high sediment influx and strong storm and wave influence, is associated with major uplift and re-orientation of the shoreline from the southwest to the northeast.


identifier: Swinden, H. S. <https://research.library.mun.ca/view/creator_az/Swinden=3AH=2E_S=2E=3A=3A.html>   (1987) Ordovician volcanism and mineralization in the Wild Bight group, central Newfoundland: a geological, petrological, geochemical and isotopic study.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
The Wild Bight Group, part of the Newfoundland Dunnage Zone or Central Mobile Belt, is a thick (probably more than 8 km.) sequence of dominantly epiclastic (~75%) and lesser volcanic (~25%) rocks which outcrops in and to the south of central Notre Dame Bay. The base of the group is not exposed. It passes conformably upward into fossiliferous shale with a Caradocian (Middle Ordovician) graptolite fauna. On this basis, it is considered as Early to Middle Ordovician in age. -- Volcanic rocks occur throughout the stratigraphic section of the Wild Bight Group. Eleven separate volcanic sequences are identified and sampled, most of which comprise dominantly or wholly mafic pillow lava. Less commonly, massive basalt or pillow breccia and associated mafic pyroclastic rocks are the dominant lithology. Felsic volcanic rocks occur in five of these sequences and volcanogenic sulphide deposits or prospects in four of them. The entire assemblage is intruded by fine to medium grained mafic sills and, less commonly, dykes, which are interpreted on field and geochemical evidence to be subvolcanic. -- The mafic volcanic rocks exhibit a greenschist facies metamorophic assemblage of chlorite - albite - quartz - epidote ± (actinolite, sphene, magnetite and calcite). The only primary mineral remaining is clinopyroxene. Comparison of secondary mineral chemistry with ancient and modern oceanic rocks and with experimental results are consistent with metamorphism at temperatures in the range 200°C to 280°C and low water/rock ratios. The local presence of secondary amphibole is interpreted to reflect slightly higher temperatures. -- Major and trace element whole rock analyses of volcanic and subvolcanic rocks, as well as clinopyroxene mineral chemistry, reveal a complex geochemical association. Two broad paleotectonic environments can be identified using high field strength elements; volcanic rocks in the lower and middle parts of the group have a clear island arc geochemical signature (negative Ta and Nb and positive Th with respect to La on a chondrite-normalized basis) whereas those in the upper parts of the group generally do not. However, basalts of both affinities occur together in one sequence at the top of the group, suggesting that magmatism of island arc and non-arc affinity overlapped in time. -- Within these two environments, further variations can be recognized. Rocks with an island arc geochemical signature include both LREE-depleted and LREE-enriched island arc tholeiites as well as a group of very incompatible element-depleted tholeiites which are interpreted to represent partial melting of refractory sources. Rocks lacking the island arc geochemical signature range from slightly LREE-enriched basalts to alkali basalts and include a group of basalts that have geochemical characteristics transitional between the two end members. Mafic subvolcanic rocks represent all of these eruptive types. -- Felsic volcanic rocks are low-K, high-SiO₂ rhyolite. They occur only in the central stratigraphic parts of the group and are associated with mafic rocks of island arc affinity. -- Petrogenetic modelling of the Wild Bight Group volcanic rocks, using a comprehensive suite of Nd isotope analyses on selected whole rocks, allows further interpretation of their origin. Rocks of island arc affinity, for the most part, have epsilon Nd in the range -1.2 to +4.8, indicating the involvement of enriched mantle sources in the magmas. Negative Nb and Ta and positive Th anomalies with respect to the LREE indicate that this component was most likely a continental crustal source from the subducting slab. The island arc tholeiites can be modelled as resulting from mixing of this crustal source and normal depleted mantle followed by varying amounts of partial melting. However, the melting history of the depleted tholeiites must be more complex, as suggested by a strong negative correlation between epsilon Nd and both Sm/Nd and atomic Mg/(Mg+Fe) (Mg#). All rocks that lack the island arc geochemical signature have epsilonNd in the range +4 to +7 and are interpreted to have resulted from varying degrees of partial melting of an ocean island basalt-type source, locally mixed with normal depleted mantle.
[Please see thesis for remainder of abstract.]