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Sedimentology

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Articles 31 - 59 of 59

Full-Text Articles in Sedimentology

Stratigraphic Architecture And Lithofacies Of High-Frequency Deltaic Sequences: Virtual Outcrop Analysis Of The Upper Cretaceous (Turonian) Ferron Sandstone Member Of The Mancos Shale, South-Central Utah, Usa, Conor J. Horton Jul 2017

Stratigraphic Architecture And Lithofacies Of High-Frequency Deltaic Sequences: Virtual Outcrop Analysis Of The Upper Cretaceous (Turonian) Ferron Sandstone Member Of The Mancos Shale, South-Central Utah, Usa, Conor J. Horton

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Sequence stratigraphic models for low-accommodation settings are not well-formulated and lack documented examples illustrating lithofacies stratal stacking pattern complexities. Presented herein is a detailed stratigraphic analysis of the Upper Cretaceous (Turonian) Ferron Sandstone Member of the Mancos Shale Formation; a fluvial-deltaic succession that primarily accumulated under forced-regressive, falling stage systems tracts during decreasing accommodation. The small (4 km2) study area is located at the connecting point of a 67 km long, depositional strike-oriented and a 30 km long, depositional-dip transect within the western-limb of the Henry Mountains Syncline. Detailed outcrop sections and digital Light Detection and Ranging (LiDAR) derived Virtual …


Slope, Grain Size, And Roughness Controls On Dry Sediment Transport And Storage On Steep Hillslopes, Roman A. Dibiase, Michael P. Lamb, Vamsi Ganti, Adam M. Booth Apr 2017

Slope, Grain Size, And Roughness Controls On Dry Sediment Transport And Storage On Steep Hillslopes, Roman A. Dibiase, Michael P. Lamb, Vamsi Ganti, Adam M. Booth

Geology Faculty Publications and Presentations

Existing hillslope sediment transport models developed for low-relief, soil-mantled landscapes are poorly suited to explain the coupling between steep rocky hillslopes and headwater channels. Here we address this knowledge gap using a series of field and numerical experiments to inform a particle-based model of sediment transport by dry ravel—a mechanism of granular transport characteristic of steep hillslopes. We find that particle travel distance increases as a function of the ratio of particle diameter to fine-scale (1m) topographic variability associated with rocky landscapes. Applying a 2-D dry-ravel-routing model to lidar-derived surface topography, we show how spatial patterns of local and nonlocal …


Sedimentology Of A Small Estuarine Marsh Along East (Pensacola) Bay, Florida, Jesse Pfadenhauer Dec 2016

Sedimentology Of A Small Estuarine Marsh Along East (Pensacola) Bay, Florida, Jesse Pfadenhauer

Honors Theses

Sediment samples from a marsh along East (Pensacola) Bay were analyzed using various laboratory techniques. The color, magnetic susceptibility, organic content, carbonate content, and sediment size distribution of each sample was measured to attain an overall profile of the sedimentary characteristics of the area. Using the GPS coordinates of each collection site, samples were categorized into sub-environments based on their position within the marsh. The trends within the study area and sub-environments were evaluated and interpreted. The data indicate that this marsh is a siliciclastic, fining-inland area that is frequently inundated with tidal fluctuations and storm surges. These storm surges …


Pore Characterizations And Distributions Within Niagaran – Lower Salina Reef Complex Reservoirs In The Silurian Northern Niagaran Pinnacle Reef Trend, Michigan Basin, Agam Arief Suhaimi Aug 2016

Pore Characterizations And Distributions Within Niagaran – Lower Salina Reef Complex Reservoirs In The Silurian Northern Niagaran Pinnacle Reef Trend, Michigan Basin, Agam Arief Suhaimi

Masters Theses

The Northern Niagaran Pinnacle Reef Trend (NNPRT) has generated significant oil and gas production in Michigan. The best reservoir rock in the Reef Trend reservoirs are from porous and permeable dolomite of the Guelph Dolomite. Low-to-non reservoir limestone occurs interstratified with reservoir dolomite in many locations. This study utilizes available cores data, thin section Petrographic Image Analysis (PIA), Mercury Injection Capillary Pressure (MICP) and a newly developed Niagaran Reef depositional model (Rine, 2015) to characterize the distribution of pore geometry within each dolomitized Niagaran Reef Complex (Brown Niagaran – Lower Salina Group) reservoir facies and lithofacies. This study shows that …


Controls On Carbonate Sedimentation And Sequence Stratigraphic Framework Of The Lower Permian (Wolfcampian) Hueco Formation (Upper-Middle And Gastropod Intervals), Robledo Shelf, Western Orogrande Basin, New Mexico, Matthew S. Harder Jan 2016

Controls On Carbonate Sedimentation And Sequence Stratigraphic Framework Of The Lower Permian (Wolfcampian) Hueco Formation (Upper-Middle And Gastropod Intervals), Robledo Shelf, Western Orogrande Basin, New Mexico, Matthew S. Harder

Open Access Theses & Dissertations

On the western margin of the Pennsylvanian/Permian Orogrande Basin, two composite measured sections in the Lower Permian upper interval of the Middle Member of the Hueco Limestone were analyzed in regards to depositional environment, facies and sequence stratigraphy. This can elucidate where potential unconventional reservoirs can be found in the Wolfcamp Shale of the Permian Basin. Based on these analyses, 12 lithofacies were identified, including 9 carbonate lithofacies: 1) fenestral dolomudstone, 2) peloidal dolomudstone, 3) ostracode foraminifera packstone, 4) foraminifera peloidal grainstone, 5) skeletal intraclast grainstone, 6) phylloid algal peloidal grainstone, 7) echinoderm phylloid algal packstone, 8) echinoderm bivalve brachiopod …


Depositional Facies And Sequence Stratigraphy Of Niagaran-Lower Salina Reef Complex Reservoirs Of The Guelph Formation, Michigan Basin, Matthew J. Rine Dec 2015

Depositional Facies And Sequence Stratigraphy Of Niagaran-Lower Salina Reef Complex Reservoirs Of The Guelph Formation, Michigan Basin, Matthew J. Rine

Masters Theses

Hydrocarbon reservoirs in the Niagara-Lower Salina Reef Complex in the Michigan Basin have been extensively studied since the early 1960’s. These reservoirs host an immense hydrocarbon resource, existing as closely-spaced, highly-compartmentalized reservoirs that have produced >500 million barrels of oil and 2.9 trillion cubic feet of natural gas. Previous studies depict these “pinnacle reefs” as tall, symmetrical towers with a random distribution of facies. This study utilizes abundant core data (32 cores, 20-acre spacing), thin-section petrography, and petrophysical wire-line logs to reconstruct the geometry, facies distributions, depositional history, and sequence stratigraphy of the Columbus III Reef Complex within the Southern …


8000 Years Of Environmental Evolution Of Barrier–Lagoon Systems Emplaced In Coastal Embayments (Nw Iberia), Rita González-Villanueva, Marta Pérez-Arlucea, Susana Costas, Roberto Bao, Xose L. Otero, Ronald J. Goble Nov 2015

8000 Years Of Environmental Evolution Of Barrier–Lagoon Systems Emplaced In Coastal Embayments (Nw Iberia), Rita González-Villanueva, Marta Pérez-Arlucea, Susana Costas, Roberto Bao, Xose L. Otero, Ronald J. Goble

Department of Earth and Atmospheric Sciences: Faculty Publications

The rocky and indented coast of NW Iberia is characterized by the presence of highly valuable and vulnerable, small and shallow barrier– lagoon systems structurally controlled. The case study was selected to analyse barrier–lagoon evolution based on detailed sedimentary architecture, chronology, geochemical and biological proxies. The main objective is to test the hypothesis of structural control and the significance at regional scale of any highenergy event recorded. This work is also aimed at identifying general patterns and conceptualizing the formation and evolution of this type of coastal systems. The results allowed us to establish a conceptual model of Holocene evolution …


Geological Controls On Stratigraphy And Sedimentation Of The Mississippian Marshall Formation, Michigan Basin, U.S.A., Joseph G. Adducci Aug 2015

Geological Controls On Stratigraphy And Sedimentation Of The Mississippian Marshall Formation, Michigan Basin, U.S.A., Joseph G. Adducci

Masters Theses

An understanding of regional orogenic, climatic, and eustatic processes is critical to the interbasinal correlation of Paleozoic strata in eastern North America. Tectonic activity associated with the culmination of Appalachian Orogenic events has been shown to have regional influence on paleostructure and sediment dispersal in the Appalachian foreland basin and adjacent intracratonic Illinois and Michigan basins. The culmination of the Acadian Orogeny at the end of the Devonian represents the beginning of a period of general tectonic quiescence extending throughout the early and middle Mississippian in eastern North America. Early Mississippian strata in the Michigan basin is distinctive and marks …


Stratigraphy And Depositional Environment Of The Mesaverde Group In The Northern Bighorn Basin Of Wyoming, Gordon Adams May 2015

Stratigraphy And Depositional Environment Of The Mesaverde Group In The Northern Bighorn Basin Of Wyoming, Gordon Adams

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

A sedimentological, stratigraphical and palynological study was conducted on the upper Cretaceous (Campanian) Mesaverde Group over 27.5 km of a north-south-orientated outcrop belt in the northern Bighorn Basin, Wyoming. During the Campanian, the study area lay in the western part of the Cretaceous Western Interior Seaway. The study aims to provide a stratigraphic and paleoenvironmental analysis of the Mesaverde Group and to integrate findings with data from outcrop belts to the south (southern Bighorn Basin), north (Montana) and east (Powder River Basin).

The Mesaverde Group (371 - 515 m thick) comprises a succession of mainly coarsening-upward stratal cycles, with some …


Using Strat Columns To Interpret Sequence Stragraphy Of Glacial Driven Stream Deposits Of The Acient San Joaquin River, Kyle R. Scharton Aug 2014

Using Strat Columns To Interpret Sequence Stragraphy Of Glacial Driven Stream Deposits Of The Acient San Joaquin River, Kyle R. Scharton

STAR Program Research Presentations

The sedimentary deposits of the ancient San Joaquin River tell the story of river flow through three glacial periods. A strat column shows vertical changes in deposition throughout an outcrop. It can be used to extrapolate the energy level of the flow, and other features of the river at different depositional environments. By looking at trends through the column it is possible to determine how the river’s flow changed through time. Variances in the gravel size and whether it supports itself or is held together by the surrounding sand matrix give clues as to the rate of flow and how …


Sedimentological And Stratigraphic Study Of A Falling-Stage Delta Complex In The Upper Cretaceous (Turonian) Ferron Sandstone Member Of The Mancos Shale, South-Central Utah, Usa, Fares Alaboud Jun 2014

Sedimentological And Stratigraphic Study Of A Falling-Stage Delta Complex In The Upper Cretaceous (Turonian) Ferron Sandstone Member Of The Mancos Shale, South-Central Utah, Usa, Fares Alaboud

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The character and distribution of lithofacies in falling-stage deltas are incompletely documented. This paper presents a sedimentological and stratigraphic evaluation of a superbly-exposed interval of Cretaceous deltaic strata that are believed to be of falling stage origin. The studied interval forms part of the Upper Cretaceous (Turonian) Ferron Sandstone Member of the Mancos Shale in the southernmost Henry Mountains Basin of south-central Utah, USA. The interval of interest is exposed in three dimensions over a 20 km2 area in a series of canyon walls. Observed facies include fine-grained mudrocks (offshore basin), mudrocks with thinly interlaminated sandstone (prodelta), thinly interbedded …


Late Mississippian (Chesterian) Through Early Pennsylvanian (Atokan) Strata, Michigan Basin, U.S.A., Shannon M. Towne Apr 2013

Late Mississippian (Chesterian) Through Early Pennsylvanian (Atokan) Strata, Michigan Basin, U.S.A., Shannon M. Towne

Masters Theses

Over 2,000 linear feet of core material was analyzed to evaluate the stratigraphy and basin evolution of Carboniferous strata in the Michigan basin. Rock units were evaluated on the basis of lithofacies type, contact relationships, and existing regional geologic interpretations. The recovery of three distinct pollen and spore assemblages from core confirms the timing of deposition during the Late Mississippian Chesterian and Early-Middle Pennsylvanian Morrowan and Atokan regional stages within the Michigan basin.

The deposition of a marine carbonate succession with significant interstratified quartz sandstone occurred during the Chesterian regional stage. The Bayport interval (Bayport Limestone) is composed of seven …


Analysis Of Depositional Facies And Geological Controls On Reservoir Quality In Lower-Middle Devonian Sylvania Sandstone, Midland County, Michigan, Katherine A. Pollard Apr 2013

Analysis Of Depositional Facies And Geological Controls On Reservoir Quality In Lower-Middle Devonian Sylvania Sandstone, Midland County, Michigan, Katherine A. Pollard

Masters Theses

The early-Middle Devonian Sylvania “Sandstone” is considered a target for potential CO2 geosequestration. In order to develop geostatic models for CO2 injection simulations, controls on reservoir properties must be addressed. The three objectives of this study involve: 1) develop an overview of depositional lithofacies and their vertical stacking relationships, 2) determine fluid sources and controls of diagenesis (dolomitization and silicification), and 3) examine geological controls on the distribution and character of reservoir facies.

The grossly transgressive Sylvania-Bois Blanc interval is a complex lithologic assemblage. Sylvania “Sandstone” strata transition from high energy, subtidal to lower-intertidal mixed carbonate-siliciclastic facies to …


The Contribution Of Small Anthropogenic Particulates (Sap) To The Sediment Load Of A Major Ephemeral Fluvial System, Santa Ana River (Sar), Southern California, Junjie Shen Jan 2013

The Contribution Of Small Anthropogenic Particulates (Sap) To The Sediment Load Of A Major Ephemeral Fluvial System, Santa Ana River (Sar), Southern California, Junjie Shen

Theses Digitization Project

This research was undertaken to explore the distribution of small anthropogenic particulates (SAP) in the Santa Ana River (SAR), and to determine the contribution of SAP to the sediment load of the SAR. SAP have never been documented before in the fluvial systems, especially in Southern California. This project will effectively establish a baseline for future changes in SAP for environmental monitoring and regulations.


Depositional Setting And Sequence Stratigraphic Analysis Of The Lower Permian Lower Hueco Formation On The Western Margin Of The Orogrande Basin, South Central New Mexico, Jonathon Eric Stautberg Jan 2013

Depositional Setting And Sequence Stratigraphic Analysis Of The Lower Permian Lower Hueco Formation On The Western Margin Of The Orogrande Basin, South Central New Mexico, Jonathon Eric Stautberg

Open Access Theses & Dissertations

On the western margin of the Orogrande Basin in south-central New Mexico, eight outcrop datasets, in the form of measured stratigraphic sections from the lower interval of the Lower Permian Lower Hueco Formation were analyzed in regard to depositional facies distribution and sequence stratigraphy. Based on petrographic analysis of 247 samples and associated field relationships, 11 depositional facies are recognized: 1) quartz sandstone, 2) quartz siltstone and shale, 3) fenestral dolomudstone, 4) microbial intraclast packstone, 5) dolomudstone, 6) green-algal packstone to grainstone, 7) ostracode foram wackestone, 8) oolitic packstone, 9) fossiliferous packstone and grainstone, 10) fusulinid packstone and grainstone, 11) …


Detrital Carbonates In A Sequence Stratigraphic Framework: An Example From The Furongian Slope Environment In The Hot Creek Range Of Central Nevada, Leon Taufani Dec 2012

Detrital Carbonates In A Sequence Stratigraphic Framework: An Example From The Furongian Slope Environment In The Hot Creek Range Of Central Nevada, Leon Taufani

UNLV Theses, Dissertations, Professional Papers, and Capstones

An integrated sedimentological study of detrital carbonates of the late Cambrian (Furongian) Hales Limestone in central Nevada was conducted in order to model facies distribution and controlling mechanisms of carbonate gravity-flow deposits. Seven closely-spaced sections and numerous traceable short sections were measured to investigate temporal and spatial changes of detrital carbonates within a high-resolution stratigraphic framework supported by biostratigraphic and carbon isotope chemostratigraphic constraints and by key physical surfaces. Polished slabs and thin section petrographic analysis were used to identify micro- and macro-scale textures and diagenesis.

Ten lithofacies are identified from the Hales Limestone. Lateral tracing of these facies reveals …


Terrestrialization In The Late Devonian: A Palaeoecological Overview Of The Red Hill Site, Pennsylvania, Usa, Walter L. Cressler Iii, Edward B. Daeschler, Rudy Slingerland, Daniel A. Peterson Jan 2010

Terrestrialization In The Late Devonian: A Palaeoecological Overview Of The Red Hill Site, Pennsylvania, Usa, Walter L. Cressler Iii, Edward B. Daeschler, Rudy Slingerland, Daniel A. Peterson

Earth & Space Sciences Faculty Publications

No abstract provided.


The Role Of Geomorphic Features And Hydrologic Processes On Sediment Clusters In Gravel-Bed Rivers, Washington: A Field-Based Approach, Ross Richard Hendrick Jan 2005

The Role Of Geomorphic Features And Hydrologic Processes On Sediment Clusters In Gravel-Bed Rivers, Washington: A Field-Based Approach, Ross Richard Hendrick

All Master's Theses

This project investigated the movement and evolution of sediment clusters after four separate flood events at two geomorphically different sites along the Entiat River, Washington. Clusters are defined as an obstacle or anchor clast(s) that impede the progress of two or more sediment particles, and are believed to be an important characteristic of the variable bed topography of gravel-bed rivers. Detailed field descriptions and digital photographs of clusters were used to determine the characteristics of clusters at chosen locations on gravel bars regularly covered by high flow events. Data were collected during low-flow conditions, and clusters were re- examined and …


Complexity Of Devonian K-Bentonites In The Appalachian Foreland Basin: Geochemical And Physical Evidence Supporting Multi-Layered K-Bentonite Horizons, Lucas Benedict Jan 2004

Complexity Of Devonian K-Bentonites In The Appalachian Foreland Basin: Geochemical And Physical Evidence Supporting Multi-Layered K-Bentonite Horizons, Lucas Benedict

Geology Theses and Dissertations

Detailed analysis of Lower to Middle Devonian K-bentonites in the Appalachian Basin reveals physical and geochemical characteristics within supposed single eruptive event deposits that indicate a more complex depositional history is recorded in many of these volcanic beds. Variations in bedding showing multiple coarse and fine-grained layers within a K-bentonite layer can be seen in some Devonian K-bentonite beds. Microscopic irregularities show variations in the orientation of volcanic grains, and subtle phenocryst layers within a K-bentonite suggest changes in depositional environment where changing water and wave regimes rework and redeposit material on the sea floor. The presence of fossil layers …


Hydrothermal Sediments Associated With A Relict Back-Arc Spreading Center In The Shikoku Basin, Recovered From The Nankai Accretionary Prism, Japan, Jane L. Alexander, Kevin T. Pickering, Elizabeth H. Bailey Jun 1999

Hydrothermal Sediments Associated With A Relict Back-Arc Spreading Center In The Shikoku Basin, Recovered From The Nankai Accretionary Prism, Japan, Jane L. Alexander, Kevin T. Pickering, Elizabeth H. Bailey

Publications and Research

The hemipelagic mudrocks of the Nankai accretionary prism, Japan, contain hydrothermal deposits associated with a relict spreading center in the Shikoku Basin. Initial work on core samples from Ocean Drilling Program Site 808 found several samples with elevated concentrations of calcium, magnesium, iron and manganese, at depths of between 1060 and 1111 m below sea floor. However, the origin of these sediments was uncertain, due to a lack of data. There was no recorded evidence of whether these elevated concentrations were present throughout this interval of core, or if they were present as discrete layers with the background hemipelagic mudrocks …


Hydrology And Sedimentology Of Dynamic Rill Networks Volume I: Erosion Model For Dynamic Rill Networks, Daniel E. Storm, Billy J. Barfield, Lindell E. Ormsbee Aug 1990

Hydrology And Sedimentology Of Dynamic Rill Networks Volume I: Erosion Model For Dynamic Rill Networks, Daniel E. Storm, Billy J. Barfield, Lindell E. Ormsbee

KWRRI Research Reports

No abstract provided.


Hydrology And Sedimentology Of Dynamic Rill Networks Volume Ii: Hydrologic Model For Dynamic Rill Networks, Lindell E. Ormsbee, George E. Blandford, John S. Montgomery, Laura B. Terrell, Billy J. Barfield, Daniel E. Storm Aug 1990

Hydrology And Sedimentology Of Dynamic Rill Networks Volume Ii: Hydrologic Model For Dynamic Rill Networks, Lindell E. Ormsbee, George E. Blandford, John S. Montgomery, Laura B. Terrell, Billy J. Barfield, Daniel E. Storm

KWRRI Research Reports

A comprehensive model has been developed for use in modeling the hydrologic response of rill network systems. The model, which is called HYMODRIN, is composed of both a hydrologic runoff component and a hydraulic channel routing component. The hydrologic component of the model uses a Green Ampt infiltration approach linked with a nonlinear reservoir runoff model. The channel routing component of the model is baaed on a finite element solution of the diffusion wave equations. In order to account for backwater effects the model employs a dual level iteration scheme.

The model may be used in either a stand alone …


Sedimentology And Tectonic Significance Of The Nutzotin Mountains Sequence, Alaska, Jane Kozinski Jan 1985

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 …


Provenance Study Of The Middle Ordovician Sandstones Of New York And Western Vermont, Stephen A. Tanski Jan 1984

Provenance Study Of The Middle Ordovician Sandstones Of New York And Western Vermont, Stephen A. Tanski

Geology Theses and Dissertations

Medial Ordovician rocks exposed in westernmost New England and eastern New York State include thick sequences of marine sandstones which are part of a belt extending from Newfoundland to Tennessee. A petrographic study was made of 237 samples distributed across the entire outcrop belt (approx. 250 km. north-south along strike and 190 km. east-west across strike).
Two distinct types of sandstone are recognized, the oldest, and most widespread, is a deep water lithic wacke deposited by turbidity currents and found interbedded with shale (flysch). The younger sandstone is found only in the southeastern part of the study area and is …


Geology Of The Fondo Negro Region, Dominican Republic, J. Calvin Cooper Jan 1983

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 …


Stratigraphy And Sedimentation Of The Spencer Formation In Yamhill And Washington Counties, Oregon, Fathi Ayoub Al-Azzaby Jan 1980

Stratigraphy And Sedimentation Of The Spencer Formation In Yamhill And Washington Counties, Oregon, Fathi Ayoub Al-Azzaby

Dissertations and Theses

The Spencer Formation in Yamhill and Washington Counties, Oregon, is exposed in a narrow belt 27 km long, from 1/4 to 3 km wide and with a maximum thickness of about 400 m. The formation is composed entirely of sandstone with interbedded thin layers of mudstone in the uppermost member. The sedimentary structure and paleoecology indicate a shallow marine depositional environment. The upper member of the Spencer Formation contains more quartz, plagioclase, and hornblende than does the lower member, but K-feldspar is less than that of the lower member. Shallower water conditions for the deposition of the upper member are …


The Development Of Foliations In Low, Medium And High Grade Metamorphic Tectonites, William J. Gregg Jan 1979

The Development Of Foliations In Low, Medium And High Grade Metamorphic Tectonites, William J. Gregg

Geology Theses and Dissertations

Studies of foliation and associated microstructures are presented from a variety of rock types and localities in the metamorphic terrains of the northeastern United States.
At Islesboro, Maine cleavage is well developed in lower greenschist grade siltstones and interbedded pelites of lower Paleozoic age. Cleavage in the siltstone units consists of two types of discrete mica films: short film segments and lengthened mica film. Thick secondary mica-rich layers are also exhibited in some siltstones. The short film segments appear to be basic elements through which cleavage development progresses by a linkage process that is poorly understood. The linkage of these …


Origin Of The Mount Merino Chert And Shale, Middle Ordovician, Eastern New York State, Dorothy M. Lang Jan 1969

Origin Of The Mount Merino Chert And Shale, Middle Ordovician, Eastern New York State, Dorothy M. Lang

Geology Theses and Dissertations

Mount Merino Chert and Shale, Middle Ordovician, is one of the most siliceous units of the Taconic sequence (eastern New York and western Vermont); it is composed of interbedded shale, siliceous hale, argillite and chert. Non-clastic quartz — aggregates of quartz having a.mosaic or felted texture — predominates in all beds, except `shale. All siliceous beds are finely laminated; most laminae are distinguished from adjacent laminae by the texture of the quartz groundmass, and the amount of clastics, carbonates, chlorite and sulphides. Statistical comparison of the textures of the quartz aggregates which occur with the other mineral components suggests that …


Surficial Geology Of The Las Vegas Quadrangle, Nevada, Charles Edgar Price Jr Jun 1966

Surficial Geology Of The Las Vegas Quadrangle, Nevada, Charles Edgar Price Jr

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Las Vegas 15-minute quadrangle, located in the south part of the state of Nevada, includes about 240 square miles in and around the city of Las Vegas; it is in the basin and range province. The quadrangle includes a broad valley floor that was once a lake bottom, a bordering area of badlands and rolling hills developed in Tertiary and Quaternary deposits, an outer marginal area of alluvial fans, and the surrounding mountains.

The mountains constitute about three per cent of the total land surface and are composed of rock ranging in are from Precambrian to Tertiary. The remainder …