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Outcrop Analog For Lower Paleozoic Hydrothermal Dolomite Reservoirs, Mohawk Valley, Ny, Brian E. Slater
Outcrop Analog For Lower Paleozoic Hydrothermal Dolomite Reservoirs, Mohawk Valley, Ny, Brian E. Slater
Geology Theses and Dissertations
Geochemical analysis and field relations of linear dolomite bodies occurring in outcrop in the Mohawk Valley of New York suggest that they have undergone significant fault-related hydrothermal alteration. The dolomite occurs in the Lower Ordovician Tribes Hill Formation, which is regionally an early Ordovician shaley limestone with patchy dolomitization. The outcrop has an en echelon fault, fracture, and fold pattern. A 3D ground penetrating radar survey of the quarry floor has helped to map out faults, fractures, anticlines, synclines and the extent of dolomitization. Most of the dolomitization occurs in fault-bounded synclines or “sags” flanked by anticlines. The dolomite structures …
Source Of Meta-Igneous Blocks And Structure Of The Colebrooke Schist In The Snowcamp Peak Area, Pickett Peak Terrane, Southwestern Oregon, Jennifer Katrib
Source Of Meta-Igneous Blocks And Structure Of The Colebrooke Schist In The Snowcamp Peak Area, Pickett Peak Terrane, Southwestern Oregon, Jennifer Katrib
Geology Theses and Dissertations
The Colebrooke Schist of the Pickett Peak terrane, southwestern Oregon, is the easternmost, structurally highest unit of the Late Mesozoic-Cenozoic Franciscan Accretionary Complex. The Colebrooke Schist consists of mostly transitional greenschist-blueschist-facies meta-sedimentary rocks with common blocks of meta-volcanics and serpentinites, rare talc-schists and meta-plutonic rocks. The Colebrooke Schist meta-volcanic blocks are greenstones, in many cases with visible relict pillow structures and relict igneous textures.
Fifteen meta-volcanic samples and one meta-plutonic sample were analyzed by XRF and ICP-MS and were plotted with analyses from Plake (1989) and Coleman (1972). The Colebrooke Schist meta-volcanic rocks plot in mid-ocean ridge basalt (MORB), island …
Convergent And Collisional Tectonics In Parts Of Oregon, Maine, And The Vermont- Quebec Border, Adam Schoonmaker
Convergent And Collisional Tectonics In Parts Of Oregon, Maine, And The Vermont- Quebec Border, Adam Schoonmaker
Geology Theses and Dissertations
Four problems of tectonic significance were addressed. The first is a study of the structural emplacement of the Snowcamp ophiolite over the Rogue-Chetco arc complex during the Nevadan Orogeny in southwestern Oregon. Similarities in age, pressure and temperature conditions during thrusting, metamorphic history, and kinematics indicate that thrusting there was correlative with the nearby Madstone Cabin thrust. This implies that the overlying ophiolitic rocks have undergone a similar history as the Josephine ophiolite and are not exotic to Jurassic North America. Two projects involve the geochemical and field relationships of rocks in north-central Maine, which are used to constrain the …
The Geology, Geochronology, Structure And Geochemistry Of The Wild Rogue Wilderness Remnant Of The Coast Range Ophiolite, Southwest Oregon: Implications For The Magmatic And Tectonic Evolution Of The Coast Range Ophiolite, Stefan Bernhard Kosanke
The Geology, Geochronology, Structure And Geochemistry Of The Wild Rogue Wilderness Remnant Of The Coast Range Ophiolite, Southwest Oregon: Implications For The Magmatic And Tectonic Evolution Of The Coast Range Ophiolite, Stefan Bernhard Kosanke
Geology Theses and Dissertations
The Wild Rogue Wilderness ophiolite (WRWO) has been correlated with the Coast Range ophiolite (CRO) and overlying Great Valley Sequence in California. The WRWO occurs on the east limb of a large Cretaceous syncline within a folded thrust sheet. The basement units strike NE, are subvertical and fault bounded and include from east to west: (1) a sheeted dike complex having gabbro screens; (2) a ductily, but heterogeneously deformed metatonalite containing abundant mylonites; (3) a heterogeneously deformed metagabbro having a relic magmatic foliation overprinted by solid-state deformation at amphibolite facies and lower grade conditions; (4) a 0.5–0.9 km wide, high-strain …
The Geology Of The Liberty-Orrington-Passagassawakeag/Fredericton Trough Terrane Boundary In The Bucksport-Orland Area, Coastal Maine, Heather A. Short
The Geology Of The Liberty-Orrington-Passagassawakeag/Fredericton Trough Terrane Boundary In The Bucksport-Orland Area, Coastal Maine, Heather A. Short
Geology Theses and Dissertations
The Liberty-Orrington fault separates two tectonic terranes of widely different lithologies and metamorphic grades within the Coastal Lithotectonic Belt of Maine. While the juxtaposition of the sillimanite-bearing Passagassawakeag gneiss and the chlorite grade Bucksport Formation (turbidites) requires a fault between them, field evidence for, and an understanding of, the nature of the fault has hitherto been lacking. Although the Liberty-Orrington fault has previously been interpreted as a thrust, strike-slip, and/or normal fault, the most recent debate has been centered around two models of Acadian amalgamation involving thrusting of the Passagassawakeag terrane from the southeast vs. thrusting from beneath central Maine …
Pre-Thrust Normal Faults And Post-Tectonic Micas In The Taconic Range Of West-Central Vermont, Nicholas W. Hayman
Pre-Thrust Normal Faults And Post-Tectonic Micas In The Taconic Range Of West-Central Vermont, Nicholas W. Hayman
Geology Theses and Dissertations
New geologic maps show that the Champlain Thrust System traces continuously between Shoreham and Benson, Vermont. The Champlain Thrust System consists of at least three internally imbricated thrust slices in continental shelf facies quartzites and carbonates. From north to south there is a structurally controlled thinning of the Champlain Thrust System, and a climbing in stratigraphic level by the thrusts. Within the Champlain Thrust System are a set of across-strike structures which create offsets in the thrusts and the surrounding lithic map unit boundaries. These structures function as lateral ramps in the thrust system geometry and bound thrust duplexes. Often …
Structure And Tectonic Significance Of Deformed Medial Ordovician Flysch And Melange Between Albany And Saratoga Lake And In The Central Hudson Valley, New York, Andreas Plesch
Geology Theses and Dissertations
The belt of medial Ordovician deformed flysch west of the traditionally defined Taconic boundary thrust was investigated by detailed mapping in the Capital District, from Albany to Saratoga Lake, and large scale compilation of the central Hudson Valley, between Glens Falls and Middletown. Maps and detailed sections are presented. Mapping recognized a two-fold division into a western belt of folded and faulted flysch and an eastern belt which is dominated by tectonic melange. The Folded and Faulted Flysch unit shows northward fining from greywacke-dominated to shale-dominated. Isoclinal folding and incipient melanges are characteristic in the south, whereas in the north …
A Kinematic Study Of The Summit Valley Plutonic Complex, Klamath Mountains, California, Nancy E. Griesau
A Kinematic Study Of The Summit Valley Plutonic Complex, Klamath Mountains, California, Nancy E. Griesau
Geology Theses and Dissertations
The Summit Valley plutonic complex (SVPC) is a multi-phase intrusive body of Late Jurassic age. Crystallization age for a zircon of 150±1 Ma and a cooling age for a hornblende of 144±1 Ma indicate a protracted period of high temperature. The SVPC is irregularly shaped, covers <15 km2, and is believed to be in the western limb of a post-Nevadan syncline, with an easterly dip estimated at about 45°. The SVPC penetrated the Orleans Fault and intruded and contact metamorphosed the upper and lower plates of the thrust. The Orleans Fault is a major tectonic boundary separating the Western Paleozoic …
The Geology Of The Vermont Valley And The Western Flank Of The Green Mountains Between Dorset Mountain And Wallingford, Vermont, Rolf Herrmann
The Geology Of The Vermont Valley And The Western Flank Of The Green Mountains Between Dorset Mountain And Wallingford, Vermont, Rolf Herrmann
Geology Theses and Dissertations
The carbonate sequence of the Vermont Valley has been generally believed to lie on the east limb of a major unfaulted syncline ("Middlebury Synclinorium"), and the exposed Precambrian basement and overlying cover rocks of the Green Mountain massif on the west limb of the adjacent major unfaulted anticline ("Green Mountain Anticlinorium"). Except for the Basal Thrust of the Taconic Allochthon, all faults shown on previous maps die out north of Dorset Mountain.
In contrast, detailed mapping for this thesis in the Vermont Valley and the western flank of the Green Mountain massif has revealed several major north/south trending thrust faults, …
Evaluation Of Computational Methods Of Paleostress Analysis Using Fault-Striation Data, Steven Henry Schimmrich
Evaluation Of Computational Methods Of Paleostress Analysis Using Fault-Striation Data, Steven Henry Schimmrich
Geology Theses and Dissertations
Over the past 12 years, many different computational methods or variations of existing methods have been proposed for determining paleostress tensors from fault populations and their slip directions. These methods are all based upon well-known relationships between stress and shear and use iterative, non-linear mathematical algorithms which seek to minimize the angles between the calculated maximum shear stress direction and the observed movement directions on each fault plane in a population. The solution returned is the best-fit paleostress tensor for the population.
By taking the Coulomb failure criterion into account, several paleostress analysis programs have been able to use linear, …
The Geology Of Taconic Thrust Sheets And Surrounding Carbonates Of The West Central Vermont Marble Belt, North Of Rutland, Vermont, Kay Bierbrauer
The Geology Of Taconic Thrust Sheets And Surrounding Carbonates Of The West Central Vermont Marble Belt, North Of Rutland, Vermont, Kay Bierbrauer
Geology Theses and Dissertations
The carbonates of the Vermont Valley and the overlying rocks of the Taconic sequence have been generally believed to lie on the east limb of a major unfaulted syncline (Middlebury Synclinorium). In this view a westward dipping, north-south trending basal Taconic overthrust must be exposed somewhere along the eastern margin of the Taconic Range.
In contrast, this study based on detailed mapping at the north end of the Taconic Allochthon suggests that a folded overthrust surface is only locally seen in fensters; more commonly the basal obduction surface of the Taconic Allochthon has been truncated by later cross-cutting thrust faults. …
Petrology Of The Kula Volcanic Field, Western Turkey, Julie M. Dyer
Petrology Of The Kula Volcanic Field, Western Turkey, Julie M. Dyer
Geology Theses and Dissertations
The Kula volcanics are a small Pleistocene to Recent volcanic field located on the north shoulder of the Gediz graben, approximately 120 km east of Izmir. The field consists of a mixture of flows, small cones and pyroclastic deposits erupted during three periods of volcanic activity beginning about one million years ago. The volcanics range in composition from basanites to trachybasalts, commonly porphyritic with abundant clinopyroxene, olivine and amphibole phenocrysts. The lavas also host a wide variety of megacrysts, crustal xenoliths and hydrous mantle-derived nodules. These volcanics unconformably overlie Neogene lacustrine sedimentary rocks and the metamorphic basement rocks of the …
Structural Analysis Across The Northeast Boundary Of The Taconic Allochthon, West-Central Vermont, Thomas E. Hoak
Structural Analysis Across The Northeast Boundary Of The Taconic Allochthon, West-Central Vermont, Thomas E. Hoak
Geology Theses and Dissertations
The Taconic Allochthon is an elongate belt of Cambro-Ordovician, argillaceous sediments with lesser occurrences of calcareous and siliceous lithologies. These lithologically distinctive strata lie tectonically juxtaposed over a coeval medial-Ordovician carbonate shelf sequence. This geometry resulted from an arc-continent collision in which a westward-migrating arc (Ammonoosuc Volcanics) collided with an eastern North America passive margin and the accumulated accretionary prism of the forearc region was thrust onto the passive continental margin.
The present thesis examined the structural sequence at the north end of the Allochthon and the continuity of this sequence into the adjacent Parautochthonous Shelf strata. Structurally, the study …
Structural Investigations On Experimentally And Naturally Produced Slickensides, Thomas Michael Will
Structural Investigations On Experimentally And Naturally Produced Slickensides, Thomas Michael Will
Geology Theses and Dissertations
This work has involved an experimental approach and a study of naturally produced slickensides.
The experiments, carried out on a pyrophyllitic rock, have been performed in order to define some extrinsic parameters that control surface and microstructural features. Normal stress, speed (i.e. strain rate), and amount of slip and total displacement were related to measureable surface features, such as length, and spacing between the developing ridges and grooves. Special attention was paid to a newly recognized type of slickenside lineation (Means, 1986). This lineation produced experimentally cannot be explained in terms of the traditional asperity ploughing or dissolution/precipitation models. It …
Sedimentology And Tectonic Significance Of The Nutzotin Mountains Sequence, Alaska, Jane Kozinski
Sedimentology And Tectonic Significance Of The Nutzotin Mountains Sequence, Alaska, Jane Kozinski
Geology Theses and Dissertations
The Nutzotin Mountains Sequence, a Mesozoic flysch sequence in the eastern Alaska Range, was studied along the southern border and in the central portions of the outcrop belt. Three lithologic associations are recognized in the Bonanza Creek section (southern margin) that together indicate a coarsening-upward trend, suggestive of a prograding fan system. These associations are (from bottom to top): 1) debris flow conglomerates overlain by 500 m of intercalated mudstone and base-missing turbiditic siltstone, and mass movement features such as slump folds and slump horizons, 2) 195 m of thicker, coarser turbidites intercalated with mudstones; turbidites are graded but lack …
The Influence Of Oceanic Transform Boundaries On The Generation And Evolution Of Oceanic Lithosphere, David G. Gallo
The Influence Of Oceanic Transform Boundaries On The Generation And Evolution Of Oceanic Lithosphere, David G. Gallo
Geology Theses and Dissertations
The first-order geologic and morphologic relationships at, along and proximal to ridge-transform-ridge plate boundaries are used to construct an empirical and speculative tectonic model. The geometry of a ridge-transform intersection necessitates the juxtaposition of relatively cold, thick lithosphere against the truncated end of an accreting plate boundary. The cold face of lithosphere cools the adjacent wedge of asthenosphere rising beneath the axis of accretion and restricts the amount of partial melting thus attenuating the amount of basaltic melt segregated from the asthenosphere per unit time. The manifestation of this cold edge effect is a thinner oceanic crust. At depth, upper …
The Tectonic Evolution Of The Eastern Yukon Tanana Upland, Alaska, Grant W. Cushing
The Tectonic Evolution Of The Eastern Yukon Tanana Upland, Alaska, Grant W. Cushing
Geology Theses and Dissertations
Field, structural, and isotopic studies in the southeastern Eagle Quadrangle reveal a complex Mesozoic history involving major metamorphism, fold development, thrusting, and igneous intrusion. These events may be related to the accretion of a terrane, possibly Stikine, to the North American continental margin.
40Ar/39Ar incremental heating experiments on metamorphic minerals from amphibolite facies rocks reveal Late Triassic to Middle Jurassic plateau ages interpreted as the age of major metamorphism. Large scale northeast trending folds within these rocks formed after the major metamorphism and before the intrusion of an undeformed, unmetamorphosed cross-cutting dike in Middle Jurassic. These folds probably developed in …
Geology Of The Fondo Negro Region, Dominican Republic, J. Calvin Cooper
Geology Of The Fondo Negro Region, Dominican Republic, J. Calvin Cooper
Geology Theses and Dissertations
Detailed geologic mapping of the Fondo Negro-Sierra de Martin Garcia region of the Southwestern Dominican Republic establishes that this area is part of a broad and diffuse Northern Caribbean plate boundary zone (PBZ). Faulting in the study area is predominantly left lateral strike-slip, with secondary compression (thrusting) causing both substantial, and rapid, uplift of the region. Folding associated with the wrench faulting affects rocks of all ages in the field area from Paleocene limestones to Quaternary alluvial fans.
New stratigraphic designations are proposed for mappable litho-units in the area, and these are correlated with Hispaniola stratigraphy in general based on …
The Pre-Tertiary Geology And Mesozoic Tectonic Evolution Of Eastern China, Southeast Asia And Adjacent Regions, Michael P. Klimetz
The Pre-Tertiary Geology And Mesozoic Tectonic Evolution Of Eastern China, Southeast Asia And Adjacent Regions, Michael P. Klimetz
Geology Theses and Dissertations
Several orogenic belts transecting south-eastern Asia are the sites of former convergent plate margins although there have been varying interpretations of the collisional framework of individual continental blocks, styles of convergence at these zones and the timing of respective collisions. A comprehensive tectonic study of eastern China, Mongolia and the southern Soviet Far East indicates the collision of the South China Block with a combined North China-Northeast China Fold Zone Block in the late Triassic-early Jurassic, their collective suturing to Eurasia in the late Jurassic-early Cretaceous, followed by the Sikhote Alin-Japan Block in the mid to late Cretaceous. The evidence …
Structure And Stratigraphy Of West Haven, Vermont, Christoph K. Steinhardt
Structure And Stratigraphy Of West Haven, Vermont, Christoph K. Steinhardt
Geology Theses and Dissertations
Mapping and structural investigations in an area bounded to to the west by by Grenvillian basement and to the east by allochthonous rocks emplaced during the medial Ordovician Taconic Orogeny led to division of the area into a Western Undeformed Zone and an Eastern Deformed Zone. The former consists of a thin, undeformed shelf sequence of upper Cambrian to lower Ordovician (Canadian) clastics and carbonates, which unconformably overlie Grenvillian basement and dip gently to the east.
The Eastern Deformed Zone consists of early to medial Ordovician carbonates folded about northnortheast trending axes with east to southeast dipping axial surfaces, overlain …
Structure And Tectonics Of The Keban Metamorphics In The Northern Margin Of The Bitlis Suture Zone, Southeastern Turkey, Gültekin Savci
Structure And Tectonics Of The Keban Metamorphics In The Northern Margin Of The Bitlis Suture Zone, Southeastern Turkey, Gültekin Savci
Geology Theses and Dissertations
The study area near Keban consists of the allochthonous Keban division of the Keban-Malatya crystalline complex and the Yuksekova island-arc rocks of the Bitlis-Puturge Complex in the northern margin of the Bitlis Suture Zone. Detailed mapping shows that the Palaeozoic-Triassic Keban Metamorphics are composed of the following formations: (1) white, massive, karstic Kirklar Marble; (2) phyllitic psammite with calcschist interlayers Calik Formation; and (3) semi-crystallized gray Koyunatlayan Limestone. These formations define a tectonostratigraphy with the Kirklar Marble at the base and the Koyunatlayan Limestone at the top. The detailed lithological description of the Keban Metamorphic rock assemblages suggest that they …
The Structural Geology Of The Tectonized Ultramafic Suite Of The Table Mountain Massif, Bay Of Islands Complex, Newfoundland, Robert Whitney Blake
The Structural Geology Of The Tectonized Ultramafic Suite Of The Table Mountain Massif, Bay Of Islands Complex, Newfoundland, Robert Whitney Blake
Geology Theses and Dissertations
Table Mountain is the northernmost massif in the Bay of Islands Ophiolite. It represents a continuous, approximately 7 kilometer thick, section of residual harzburgite tectonites capped by a nearly flat-lying assemblage of deformed and undeformed cumulate rocks. The notable mesoscopic structural features of the massif include a zone of penetrative deformation extending upsection from the tectonized harzburgites approximately 500 meters into the dunites and basal cumulates. The orientation of the foliation and associated lineations as well as the inferred shear sense within the zone is consistent with that affecting the harzburgites. Highly deformed dunite lenses which range in thickness up …
Structure Of The Northern Margin Of The Bitlis Suture Zone Near Sivrice, Southeastern Turkey, Mark R. Hempton
Structure Of The Northern Margin Of The Bitlis Suture Zone Near Sivrice, Southeastern Turkey, Mark R. Hempton
Geology Theses and Dissertations
Detailed mapping near Sivrice shows that the northern margin of the Bitlis Suture zone consists of three major tectonostratigraphic units outcropping as distinct north-dipping thrust slices. From south to north these are: (1) the Pütürge Complex; (2) the Maden Complex; and (3) the Elazig Complex.
The pre-Eocene Pütürge Complex consists of 80% metapelite, 15% metaquartzite, and 5% recrystallized limestone. These rocks represent a continental margin sequence that has been metamorphosed to the lower greenschist facies. There are three generations of structural elements: (1) a transposition foliation and macroscopic isoclinal folds, (2) a crenulation cleavage and mesoscopic folds, and (3) kink …
Permo-Triassic Reconstruction Of Western Pangea And The Evolution Of The Gulf Of Mexico-Caribbean Region, James Lawrence Pindell
Permo-Triassic Reconstruction Of Western Pangea And The Evolution Of The Gulf Of Mexico-Caribbean Region, James Lawrence Pindell
Geology Theses and Dissertations
A Permo-Triassic reconstruction of western Pangea (North America, South America, Africa) is proposed that is characterized by: 1) definition of the North Atlantic fit by matching of marginal offsets (fracture zones) along the opposing margins, 2) a South Atlantic fit that is tighter than the Bullard fit and that is achieved by treating Africa as two plates astride the Benue Trough and related structures during the Cretaceous, 3) complete closure of the Proto-Atlantic Ocean between North and South America, accomplished by placing the Yucatan block between the Ouachita Mountains and Venezuela, 4) a proposed Hercynian suture zone that separates zones …
Structural Studies Of The Ordovician Flysch And Melange In Albany County, New York, Frederick W. Vollmer
Structural Studies Of The Ordovician Flysch And Melange In Albany County, New York, Frederick W. Vollmer
Geology Theses and Dissertations
The middle Ordovician rocks of the Albany 15 minute quadrangle comprise interbedded graywacke and shale, and in the east, coarse cobble or olistostromic deposits. The detrital composition, westward fining and regional westward transgression of these deposits indicate that these were sediments shed off the westward thrusting Taconic Allochthon. Primary sedimentary structures show that these rocks were deposited by turbidity currents flowing into a longitudinal trough, probably formed in response to increased load during overthrusting. Although strongly dependent on lithology, deformation intensity generally increases from west to east; from essentially undeformed bedded flysch through asymmetrically folded and thrust beds to highly …
Complex Structure And Stratigraphy Of Lower Slices Of The Taconic Allochthon Near Middle Granville, New York, David B. Rowley
Complex Structure And Stratigraphy Of Lower Slices Of The Taconic Allochthon Near Middle Granville, New York, David B. Rowley
Geology Theses and Dissertations
The Precambrian (?) to medial Ordovician rocks of the Taconic Allochthon are characterized by argillaceous and arenaceous sediments with lesser associated carbonates, carbonate breccias, and cherts of predominantly deep-water aspect. These allochthonous rocks tectonically overlie an autochthonous to parautochthonous coeval sequence of dominantly shallow marine clastics and carbonates of the Champlain and Vermont Valley sequences. Facies, thickness, sedimentologic, and paleontologic considerations suggest that these coeval sequences represent a carbonate shelf continental rise pair of the east-facing early Paleozoic Atlantic-type margin of North America. This margin formed by the opening of an ocean in latest Precambrian time. The stratigraphy of the …
Theoretical And Computer Assisted Studies In Tectonics, Structural Geology And Isotope Dating, Richard Leigh Thiessen
Theoretical And Computer Assisted Studies In Tectonics, Structural Geology And Isotope Dating, Richard Leigh Thiessen
Geology Theses and Dissertations
Several problems in the fields of tectonics, structural geology and isotopic dating were examined and simplified using computer programs. These problems include the theory of refolding, refold applications to three mining areas, hotspots and their relationship to mantle convection systems and ionium dating of volcanic rocks. In the first study, it was shown that current refold classification schemes are inadequate and so modifications were suggested. Various other aspects of multiple generations of interfering folds were also examined. The ideas of refold theory were then applied to three mining areas, the Chisel Lake Ore Body of Manitoba, the Galena-Roubaix District of …
The Geology Of The Northern Part Of North Arm Massif, Bay Of Islands Ophiolite Complex, Newfoundland: With Application To Upper Oceanic Crust Lithology, Structure, And Genesis, Eric J. Rosencrantz
The Geology Of The Northern Part Of North Arm Massif, Bay Of Islands Ophiolite Complex, Newfoundland: With Application To Upper Oceanic Crust Lithology, Structure, And Genesis, Eric J. Rosencrantz
Geology Theses and Dissertations
Detailed mapping (1:15,800) of the northern half of North Arm Massif shows the area to be underlain with a complete, although thin, ophiolite assemblage consisting, from top to base, of basalts, sheeted diabase dikes, isotropic and layered gabbroic rocks, layered ultramafic rocks and harzburgite tectonite. The assemblage represents a preserved piece of Cambrian oceanic crust analogous to present-day oceanic crust. Sheeted dikes and isotropic gabbros comprise the majority of the rocks exposed, with this sequence at present flat-lying to gently warped into open, upright but nonsystematic folds. Basalts occupy a shallow discontinuous N-S trending trough within the west-central part of …
The Geology Of The Southern Part Of The North Arm Mountain Massif, Bay Of Islands Ophiolite Complex, Western Newfoundland With Application To Ophiolite Obduction And The Genesis Of The Plutonic Portions Of Oceanic Crust And Upper Mantle, John F. Casey
Geology Theses and Dissertations
The Bay of Islands Ophiolite Complex forms a discontinuous belt of highly allochthonous mafic and ultramafic massifs in southwestern Newfoundland. The North Arm Mountain Massif contains the only significant exposures of sedimentary rocks overlying the ophiolite and also contains the most extensive exposures of plutonic rocks in the Bay of Islands Complex. Mapping has shown that sedimentary rocks, here named the Crabb Brook Group, rest with a pronounced erosional unconformity on ophiolitic rocks. Lithologic,paleontologic, facies, structural, and tectonic relationships indicate that this Group was deposited on the back of the ophiolite allochthon as it was being obducted onto the early …
Saratoga: The Bubbles Of Reputation And Their Implications For An Embryonic Rift System In The Upper Hudson River Valley, James R. Young
Saratoga: The Bubbles Of Reputation And Their Implications For An Embryonic Rift System In The Upper Hudson River Valley, James R. Young
Geology Theses and Dissertations
Carbonated, alkaline, saline waters occur over a wide area in the upper Hudson River Valley approaching 1,000 square miles. Through the sampling (spring and fall) of 39 locations, half of which were hitherto unsampled, the waters are shown to be a complexly mixed system with at least five major components.
They are:
1) a gaseous phase consisting primarily of CO2;
2) a fluid (containing the dissolved CO2) possibly analogous to a metamorphic brine whose major chemistry is HCO3>Na>Cl;
3) formational waters of variably low salinities which may be the end products of progressive dilution of Paleozoic connate brines …