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Theses/Dissertations

Geology

University at Albany, State University of New York

1987

Articles 1 - 8 of 8

Full-Text Articles in Physical Sciences and Mathematics

Petrology Of The Kula Volcanic Field, Western Turkey, Julie M. Dyer Jan 1987

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 …

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Structural Analysis Across The Northeast Boundary Of The Taconic Allochthon, West-Central Vermont, Thomas E. Hoak Jan 1987

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 …

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Granitic Pegmatites In The Southeastern Adirondacks: Their Use As Indicators Of Temperature, Pressure, And Fluid Conditions During A Late Stage Of The Grenville Orogeny, John P. Mihalich Jan 1987

Granitic Pegmatites In The Southeastern Adirondacks: Their Use As Indicators Of Temperature, Pressure, And Fluid Conditions During A Late Stage Of The Grenville Orogeny, John P. Mihalich

Geology Theses and Dissertations

Granitic pegmatites associated with the Grenville orogeny intrude a mid-Proterozoic, upper amphibolite to near granulite facies terrane in the southeastern Adirondack Mountains of New York State. The inferred anatectic, fluid-saturated, and minimum melt characteristics of the pegmatites suggest that they can be used as analogs of the "granite" or "haplogranite" system, and as indicators of crustal temperature, pressure, and fluid conditions during a late stage of the Grenville orogeny. Bulk chemical compositions of seven simple, undeformed pegmatites in the southeastern Adirondacks indicate that they are generally depleted in silica and sodium, and enriched in potassium, relative to experimental data on …

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Geology, Geochemistry, And Geochronology Of The Lems Ridge Olistostrome, Klamath Mountains, California, Matthias Ohr Jan 1987

Geology, Geochemistry, And Geochronology Of The Lems Ridge Olistostrome, Klamath Mountains, California, Matthias Ohr

Geology Theses and Dissertations

The Lems Ridge olistostrome (LRO), located within the western Jurassic belt of the Klamath Mountains geologic province, is a melange unit showing a distinct block-in-matrix fabric. The conformable relationship to both an igneous basement and the overlying flysch of the Late Jurassic Galice Formation points to a sedimentary origin. The lack of pervasive deformation and the internal stratification also support a predominantly olistostromal origin of the LRO. The matrix of the LRO consists of pebbly mudstone which interfingers with tuffaceous greenstone and tuff-breccias. Subordinate beds of chert, argillite, and sandstone are also present. The matrix contains abundant ophiolitic clasts, fragments …

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The Providence Island Formation In The Northern Appalachian Region - A Lower-Lower Middle Ordovician Analogue To Recent Arid-Semiarid Tidal-Flat Carbonates Of The Persian Gulf Trucial Coast, Mauricio Roma Hernandez Jan 1987

The Providence Island Formation In The Northern Appalachian Region - A Lower-Lower Middle Ordovician Analogue To Recent Arid-Semiarid Tidal-Flat Carbonates Of The Persian Gulf Trucial Coast, Mauricio Roma Hernandez

Geology Theses and Dissertations

The Providence Island Formation of Early-early Middle Ordovician age occurs in the Champlain Valley and adjacent areas in eastern New York, western Vermont, and southern Quebec. The unit forms part of a carbonate shelf sequence which occupied the eastern margin of the North American continent from Newfoundland to Alabama, and its lithology is representative of the dolostone lithofacies that characterizes the uppermost Beekmantown Group in this region.
This is the first study documenting depositional environments, diagenesis, and stratigraphic correlations of the Providence Island Formation. This formation consists, in decreasing abundance, of dolostones, limestones, shales, and dedolostones. The dominantly fine grain …

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Geology Of The Northern Baie Verte Peninsula, Newfoundland, Canada, Pamela J. Stella Jan 1987

Geology Of The Northern Baie Verte Peninsula, Newfoundland, Canada, Pamela J. Stella

Geology Theses and Dissertations

On the eastern portion of the Burlington Peninsula of northwest central Newfoundland, Canada, there are two different age groups of volcanic and volcaniclastic rocks. There have been arguments in the past as to whether or not these two groups are actually only one group (Cape St. John Group) but with progressive intensity of deformation and metamorphism from south to north. Other workers have divided the rocks into two distinct groups, the Grand Cove Group and the Cape St. John Group based on their differences in deformation style and metamorphic grade. This study ignored previous divisions of the rocks into one …

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Structural Investigations On Experimentally And Naturally Produced Slickensides, Thomas Michael Will Jan 1987

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 …

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Identification Of Endmembers For Magma Mixing In Little Sitkin Volcano, Alaska, Douglas A. Wolf Jan 1987

Identification Of Endmembers For Magma Mixing In Little Sitkin Volcano, Alaska, Douglas A. Wolf

Geology Theses and Dissertations

Little Sitkin island is an Aleutian calc-alkalic volcanic center that has erupted a suite of lavas ranging from andesite through rhyodacite. Whole-rock chemistry of these lavas indicates contrasting evolutionary processes; major-oxide silica variation diagrams exhibit linear trends that are suggestive of magma-mixing while trace-element trends are largely controlled by accessory-phase fractionation.
Plagioclase, the dominant phenocryst phase in all lavas, commonly occurs in two distinct populations with markedly different compositions and textures. Both normal and reverse zonation is noted in the plagioclase and clinopyroxene of several samples. In addition, clinopyroxene is found as rims on orthopyroxene grains and as cores with …

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