Geology Commons^™

Geology In The Vicinity Of The City Of Fossil, Wheeler County, North-Central Oregon, Patrick W. Riseley

Loma Linda University Electronic Theses, Dissertations & Projects

The area of study is located on the north flank of the northeast-southwest trending Blue Mountains Anticlinorium in north-central Oregon. The primary geologic problems investigated were: 1) the age and stratigraphic position of leaf-bearing tufts mapped as Oligo-Miocene John Day Formation but surrounded by andesitic basalts of the Eo-Oligocene Clarno Formation, 2) the age of "olivine basalt" mapped as John Day Formation by some workers but referred to the Clarno Formation by others, and 3) the petroleum potential of the Fossil area.

To resolve these three problems I mapped a 25 square mile area surrounding Fossil at 1 :24,000 scale. …

Taylor Instability In Ryholite Lava Flows, B. A. Baum, W. B. Krantz, Jonathan H. Fink, R. E. Dickinson

Geology Faculty Publications and Presentations

A refined Taylor instability model is developed to describe the surface morphology of rhyolite lava flows. The effect of the downslope flow of the lava on the structures resulting from the Taylor instability mechanism is considered. Squire's (1933) transformation is developed for this flow in order to extend the results to three-dimensional modes. This permits assessing why ridges thought to arise from the Taylor instability mechanism are preferentially oriented transverse to the direction of lava flow. Measured diapir and ridge spacings for the Little and Big Glass Mountain rhyolite flows in northern California are used in conjunction with the model …

Groundwater Flow Systems And Thermal Regimes Near Cooling Igneous Plutons: Influence Of Surface Topography, Mark U. Birch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Previous studies of cooling igneous plutons did not consider the possible influence of sloping surface topography. Topographically-driven fluids in high relief terrain, however, are thought to interact with deep buoyancy-driven fluids to produce large lateral-flow systems up to 5 km long and 20 km long in silicic and andesitic volcanic terrain, respectively. In this study, a quantitative investigation of the interaction of topographically-driven and buoyancy-driven fluid flow is conducted through the use of a finite element numerical model to simulate the fluid flow and thermal regimes associated with a cooling igneous pluton in the presence of significant topographic relief. The …

The Geology And Structural Significance Of The Arch Mountain Area, Northern Black Mountains, Mohave County, Arizona, Edward Eschner

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Arch Mountain area of northwestern Mohave County, Arizona, is typified by rocks that range from Precambrian to Quatemary in age. Arch mountain is a north-trending horst bounded on the west by the Petroglyph Wash graben and on the east by the Virgin Basin. A low-angle normal fault, herein named the Arch Mountain detachment fault, is exposed for 6 km along strike just below the ridge crest of Arch Mountain, and it is typified by a 2-20 cm thick zone of hematite-impregnated breccia and cataclasite. The detachment fault places an upper plate of Precambrian gneiss, Paleozoic quartzite, shale and dolomite, …

Footwall Deformation And Structural Analysis Of The Footwall Of The Willard Thrust Fault, Northern Wasatch Range, Utah, Douglas Scott Neves

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Deformation mechanisms in the footwall of the Willard thrust fault, northern Wasatch Range, Utah, change from dominantly plastic to dominantly cataclastic (both microscopically and macroscopically) in the Ophir Formation and Maxfield Limestone before the thrust begins to ramp laterally upsection southward, just to the north of the North Ogden Canyon field area. This transition in compressional deformation style and mechanism is located within a lateral distance of 3.2-kilometers along the 22-kilometer long trace of the thrust fault.

Between Willard Canyon and North Ogden Canyon penetrative deformation is localized within 200 meters of the thrust surface and is characterized by transposed …

Origin And Evolution Of Dolostone In The Middle Cambrian Langston Formation, Northern Utah, Mark C. Hall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Six major generations of dolomite are present within the Cambrian Langston Formation in the Wellsville Mountains and Bear River Range of northern Utah. Identification of dolomite generations and delineation of their relative sequences are based on normal light petrography, cathodoluminescence, staining, chemistry, inferred burial history, and deformation features. The earliest stage is believed to be Middle to Late Cambrian in age. The presence of dolomite rhombs and dolomitized echinoid fragments and peloids suggests that this stage probably formed under sabkha reflux conditions. Extensive nonferroan, polymodal, nonplanar ("xenotopic") dolomite formed next under confined mixing zone conditions. A succeeding generation of pervasive …

The Style Of Late Cenozoic Deformation At The Eastern Front Of The California Coast Ranges, Carl M. Wentworth, Mark D. Zoback

United States Geological Survey: Staff Publications

The 1983 Coalinga earthquake occurred at the eastern boundary of the California Coast Ranges in response to northeast directed thrusting. Such movements over the past 2 Ma have produced Coalinga anticline by folding above the blind eastern tip of the Coalinga thrust zone. The 600-km length of the Coast Ranges boundary shares a common structural setting that involves westward upturn of Cenozoic and Cretaceou strata at the eastern front of the Coast Ranges and a major, southwest facing step in the basement surface beneath the western Great Valley. Like Coalinga anticline, Pliocene and Quaternary folding and faulting along the rest …

Seismic Signature Of A Swan Hills (Frasnian) Reef Reservoir, Snipe Lake, Alberta, Neil Lennart Anderson, Robert James Sidford Brown, Ronald C. Hinds, L. V. Hills

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Swan Hills formation (Frasnian stage) carbonate buildups of the Beaverhill Lake group are generally of low relief and considerable areal extent and are overlain by and encased within the relatively high-velocity shale of the Waterways formation, which thins but does not drape across the reefs. Consistent with this picture, prereef seismic events are not significantly pulled up beneath the reefs nor are postreef events draped across them. Indeed, the seismic images of these reefs are effectively masked by the high-amplitude reflections from the overlying top of the Beaverhill Lake group and underlying Gilwood member and cannot be distinguished from those …

Analysis Of Hydrogeologic Sensitivity In Winona County, Minnesota, Michael D. Trojan, James A. Perry

Journal of the Minnesota Academy of Science

Hydrogeologic sensitivity to contamination throughout Winona County in southeastern Minnesota was assessed using the recently developed Trojan-Perry rating method. Sensitivity varied across and within three analysis regions. The Prairie du Chien Aquifer, comprising Region I, showed a wide range of sensitivity, varying from moderate to extreme. Areas of greatest sensitivity were sites where the aquifer was unconfined and overlain by a thin layer of unconsolidated material and karst bedrock. Under these conditions water may rapidly infiltrate through the soil zone and highly dissolved bedrock and into underlying aquifers. The Ironton-Galesville Aquifer, comprising Region II, was protected from surface infiltration by …

Geographic Information Systems, Data, And Water Resources, Dwight A. Brown, Philip J. Gersmehl

Journal of the Minnesota Academy of Science

ABSTRACT-We evaluate three data handling methods for use in a GIS analysis of land-cover change impacts on runoff. A universe of 2560 point samples is analyzed to provide runoff calculations that would se1:7e _as a comparison base to evaluate different attribute logic systems. The attribute logics ~e evaluate are two va~1at1ons of tag and one of count. We chose a two by five mile area of Dakota County, Mmnesota as the test site, and prepared raster GIS maps of soil hydrologic groups and two plausible land covers. The count 1:1~thod for handling the generalization of data produced results that were …

Water Quality In Southeastern Minnesota Streams: Observations Along A Gradient Of Land Use And Geology, Nels H. Troelstrup Jr., James A. Perry

Journal of the Minnesota Academy of Science

ABSTRACT-Surface water quality in southeastern Minnesota's driftless area exhibits subregional and local spatial patterns which are highly correlated with subsurface geology and land-use practices. Some variables appear to respond on subregional or watershed scales. Nitrate, specific conductance, alkalinity, and surface water atrazine concentrations were lower in streams originating from the Prairie Du Chien or Jordan sandstone ~quifers of easte:n Fillmore and Houston Counties than those originating from the Galena limestone aquifer m west-central Fillmore County. In addition, the numbers of pollution intolerant and functionally specialized invertebrates in the benthic community were higher in the eastern streams. Gross primary production on …

Origin And Developmental History Of Minnesota Lakes, H. E. Wright Jr.

Journal of the Minnesota Academy of Science

ABSTRACT-Most lakes in Minnesota owe their origin directly or indirectly to glacial deposition or erosion 10,000 to 20,000 years ago. The lakes' shapes have since been modified by waves and currents near the shores and by the deposition of sediment off-shore-principally the sediment produced by growth of algae and other organisms. This sediment is a receptacle for pollen grains blown into the lake from the surrounding vegetation, and the stratigraphic succession of pollen grains records the postglacial vegetational and thus climatic history of the area. The sediment also preserves the fossils of microorganisms that reveal by their chemical composition the …

Natural And Anthropogenic Forces Acting On A Forest Lake, M. C. Whiteside, M. B. King, K. Pulling

Journal of the Minnesota Academy of Science

ABS1RACT-Lak~ Itasca, Minnes~ta is located within one of the more popular state parks. Since the turn of the centmy, loggmg, fire protection, and development within the watershed have put modest pressures on the ecosystem. The presence of the University of Minnesota's Biological and Forestry Station on the lake has encouraged research in this region. Consequently there are numerous research reports and papers which are available _at the station's library. We examined data collected over the past 25 years to see if we could detect changes ~~ the lake. We detected no changes in phytoplankton, macrophyte, zooplankton, or zoobenthos com~urnues, but …

A Hydrologic Model For Minnesota Peatlands, Kenneth N. Brooks, Dawn R. Kreft

Journal of the Minnesota Academy of Science

ABSTRACT-The Peatland Hydrologic Impact Model (PHIM) is a continuous simulation computer model developed over a twelve-year period to aid hydrologists in understanding the hydrologic functions of peatlands and upland-peatland watersheds. An initial conceptual model defined the research needed to create the working m?del. The re~e_arch has become an iterative process of model design, field work, model refinement, ~ode! test1?g, an~ add1t1?nal field work. The model is as physically-based as possible while relying on data mput that 1s readily available to the natural resources community. It simulates streamflow response of peatlands, upland-peatland systems, mined peatlands, and a combination of these watershed …

Geology Of The Pre-Dune Strata, James B. Swinehart, Robert F. Diffendal Jr.

School of Natural Resources: Faculty Publications

Over the last 98 million years, four general geological processes have acted to shape the ancient landscapes buried beneath the Sand Hills. Three of these affected the area directly, either depositing sediments on the land surface or eroding it, while a fourth took place west of Nebraska, but affected the region nonetheless.

Shells of clams, oysters, and numerous other kinds of creatures similar to forms that live today in the seas are preserved as fossils in the chalks, limestones, and shales that form the oldest rocks beneath the Sand Hills that will be described. These deposits indicate to geologists that …

Late Pennsylvanian And Early Permian Cyclic Sedimentation, Paleogeography, Paleoecology, And Biostratigraphy In Kansas And Nebraska, Roger K. Pabian, Robert F. Diffendal, Jr. Jr.

Robert F. Diffendal, Jr., Publications

Overview of Upper Pennsylvanian Cyclic Sedimentation in Kansas and Nebraska, Philip H. Heckel, Department of Geology, University of Iowa, Iowa City, Iowa

With contributions from:

Christopher G. Maples and W. Lynn Watney, Kansas Geological Survey, Lawrence, Kansas

John Harris, Shell Western Exploration and Production, Inc., Houston, Texas

David Ball, Champlin Petroleum Company, Houston, Texas

Philip H. Heckel, University of Iowa, Iowa City, Iowa

R. R. West, V. Voegeli, S. Roth, K. Leonard, H. R. Feldman, and C. Cunningham, Kansas State University, Manhattan, Kansas

Royal H. Mapes, Ohio University, Athens, Ohio

Hans-Peter Schultze, University of Kansas, Lawrence, Kansas

R. Matt Joeckel, …

Lake Maloney Quadrangle, Nebraska--Lincoln County, 7.5 Minute Series (Topographic), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

7.5 minute series (topographic)

100° 45' to 100° 52' 30"

41° 00' to 41° 07' 30"

Includes Ogallala Outcrops (pencil)

Pisces Iv Submersible Observations In The Epicentral Region Of The 1929 Grand Banks Earthquake, John E. Hughes Clarke, Larry A. Mayer, David J.W. Piper, Alexander N. Shor

Affiliate Scholarship

The PISCES IVsubmersible was used to investigate the upper continental slope around 44 ON, 56" W, near the epicentre of the 1929 Grand Banks earthquake. Four dives in water depths of 800-2000 m were undertaken to observe speci3c features identijied with the SeaMARC I sidescan system in 1983. Two dives were made in the head of Eastern Valley where pebbly mudstones ofprobable Pleistocene age were recognized outcropping on the seafloor. Constructional features of cobbles and boulders, derived by exhumation and reworking of the pebbly mudstone, were also observed. These include gravel/sand bedforms (transverse waves) on the valley floor. Slope failure …

Lithostratigraphy, Biostratigraphy, And Stable-Isotope Stratigraphy Of Cores From Odp Leg 105 Site Surveys, Labrador Sea And Baffin Bay, D. B. Scott, P. J. Mudie, A. De Vernal, C. Hillaire-Marcel, V. Baki, K. D. Mackinnon, F. S. Medioli, Larry A. Mayer

Affiliate Scholarship

Trigger weight (TWC) and piston (PC) cores obtained from surveys of the three sites drilled during Ocean Drilling Program (ODP) Leg 105 were studied in detail for benthic foraminiferal assemblages, total carbonate (all sites), planktonic foraminiferal abundances (Sites 645 and 647), and stable isotopes (Sites 646 and 647). These high-resolution data provide the link between modern environmental conditions represented by the sediment in the TWC and the uppermost cores of the ODP holes. This link provides essential control data for interpretating late Pleistocene paleoceanographic records from these core holes. At Site 645 in Baffin Bay, local correlation is difficult because …

The Influence Of Biogenic Silica On Seismic Lithostratigraphy At Odp Sites 642 And 643, Eastern Norwegian Sea, Peter Hempel, Larry A. Mayer, Elliot Taylor, Gerhard Bohrmann, Alan Pittenger

Affiliate Scholarship

Drilling at ODP Sites 642 and 643 revealed a 250 m-thick section of diatomaceous Pliocene to Miocene sediments on the outer Vdring Plateau, eastern Norwegian Sea. These biogenic silica-rich sediments have a significantly lower saturated bulk density than the surrounding sediments, causing a decrease in acoustic impedance, which is seismically expressed as a negative polarity reflection. Variations in sonic velocity, the other key parameter in seismic analysis, is only of secondary importance in creating impedance contrasts in our study. Synthetic seismograms were produced from shipboard physical property measurements corrected for in situ conditions. These synthetic seismograms are in good agreement …

Ua66/8/2 Earthquake Risk Assessment For Warren County, Kentucky, Wku Center For Local Government, Nicholas Crawford, Thomas Tweddell, Shaun Winter, Peter Erlenbach, Amy Huot, Grant Whittle

WKU Administration Documents

Earthquake risk assessment report for Bowling Green and Warren County, Kentucky. Include illustrations and maps.

Geologic Evolution Of Trail Ridge Eolian Heavy-Mineral Sand And Underlying Peat, Northern Florida, Eric Force, Fredrick J. Rich

Earth, Environment & Sustainability: Faculty Publications

The southern portion of Trail Ridge in Clay County, Fla., has been an important domestic source of altered ilmenite, zircon, and other minerals since 1949. The ridge as a physiographic feature extends in a north-south direction over 160 km and is 1 to 2 km wide. The ore is a fine- to medium-grained sand body that extends down from the crest of the ridge about 20 m. Average heavy-mineral content is about 4 percent. Over half of the ilmenite and zircon is contained in thin, dark laminae dipping 26° to 41 ° southwest; these laminae extend deep within the ore …

Distribution Patterns And Accumulation Rates Of Fine-Grained Sediments In Upper Tampa Bay, Florida, Gregg R. Brooks

Reports

Tampa Bay, a drowned river valley, is the largest estuary on Florida's west coast.

Surface sediments consist of a mixture of carbonate and terrigenous clastic sands and muds.

The objectives of this study are to determine accumulation rates and processes controlling the distribution patterns of fine grain sediments.

Comparative Morphologic Analysis And Geochronology For The Development And Decline Of Two Pleistocene Coral Reefs, San Salvador And Great Inagua Islands, Bahamas, H. Allen Curran, Brian White, J. H. Chen, G. J. Wasserburg

Geosciences: Faculty Publications

Reprinted from: John E. Mylroie (ed.), Proceedings of the 4th Symposium on the Geology of the Bahamas: San Salvador, Bahamian Field Station.

Pleistocene And Holocene Carbonate Environments On San Salvador Island, Bahamas: A Field Trip Guide, H. Allen Curran, Roger J. Bain, James L. Carew, John E. Mylroie, James W. Teeter, Brian White

Geosciences: Faculty Publications

Although isolated and small in size, San Salvador Island is in many ways a unique place - an all carbonates setting on a small, tectonically stable platform, surrounded by deep oceanic waters, and an historical footnote as the widely accepted first landing site of Christopher Columbus in the New World in 1492. Columbus' stay here was brief, and the major events of subsequent history largely have passed San Salvador by. This is not a tourist island; the natural beauty, floras, and faunas of the Bahamas are well preserved here.

The overview theme of this series of field excursions on San …

Johnson County Test Hole Logs, Raymond R. Burchett, Frank A. Smith

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Guide To Interpretation Of Structural Features Associated With The Kentucky River Fault System Along U.S. Highway 27 Near Camp Nelson, Kentucky, J. A. Gilreath, Paul E. Potter, George Losonsky

Map and Chart--KGS

The spectacular, near- vertical roadcuts in the High Bridge Group (Middle Ordovician) in central Kentucky (Fig. 1) along U.S. Highway 27 just south of the Kentucky River (Fig. 2) afford an excellent opportunity to examine a major fault zone and study its complexity (Figs, 3, 4). These roadcuts are located in Garrard County approximately 12 miles south of Lexington and contain the oldest rocks exposed in Kentucky.

Index To Oil And Gas Fields Of Kentucky, Brandon C. Nuttall

Information Circular--KGS

These data have been collected by the Kentucky Geological Survey as part of an ongoing project, and this report is subject to updating and revision as additional data become available. Where information is not available for a certain category, the entry is left blank.

Data are listed in order by county and field name. Producing formations generally are listed in approximate stratigraphic sequence from youngest to oldest. The date shown is the year of completion of the discovery well in the field. The Carter coordinate location pertains only to the discovery well of the field and in some cases may …

40ar/39ar Age Constraints On Deformation And Metamorphism In The Maine Central Thrust Zone And Tibetan Slab, Eastern Nepal Himalaya, Mary S. Hubbard, T. M. Harrison

Geosciences Faculty Publications

No abstract provided.

Depositional Environments And Diagenesis Of The Lower Duperow Formation (Devonian), Billings Anticline, North Dakota, Randolph B. Burke

Theses and Dissertations

The Duperow Formation is an Upper Devonian (Frasnian) subsurface unit in the Williston Basin in the north-central United States and south-central Canada. Despite its economic importance for hydrocarbons, no detailed accounts have been published on the Duperow Formation that integrate depositional environments, lithology, diagenesis, and pore studies on either a regional or local scale. It was the purpose of this study to construct a model of the depositional environments and diagenesis of the lower Duperow Formation in the Billings Anticline of west-central North Dakota, based on detailed analysis of 17 cores (225 m, 739 ft) and associated wireline logs and …