Geology Commons^™

Effective Elastic Thickness Of The Lithosphere Along The Easter Seamount Chain, Sarah E. Kruse, Zhengro J. Liu, David F. Naar, Robert A. Duncan

Geology Faculty Publications

Bathymetry and gravity data collected during Legs 5, 6, and 7 of the 1993 GLORIA Expedition and the recently released 2-min altimetry-derived global gravity grid are used to determine the effective elastic thickness of the lithosphere along the Easter Seamount Chain (ESC). Forward modeling, admittance, and coherence methods yield consistent results. With the exception of the eastern and western ends of the ESC the effective elastic thickness along the chain is ∼1–4 km. The thin elastic thickness for the majority of the ESC seamounts is compatible with a young seafloor age at the time of loading derived from new radiometric …

The Marine Pleistocene Sediments Andn Paleogeography Of The Southern Thrace Coast, Mehmet Sakinç, Cenk Yaltirak

Bulletin of the Mineral Research and Exploration

No abstract provided.

Anatomy Of An Epithermal Mineralization: Mumcu (Balikesi̇r-Sindirgi), Inner-Western Anatolia, Turkey, Vedat Oygür

Bulletin of the Mineral Research and Exploration

No abstract provided.

Geology Of The İdi̇ş Daği - Avanos Area (Nevşehi̇r - Central Anatolia), Serhat Köksal, M. Cemal Göncüoğlu

Bulletin of the Mineral Research and Exploration

No abstract provided.

Volcanology And Geochemistry Of Pliocene And Quaternary Basalts On Citadel Mountain, Lunar Crater Volcanic Field, Pancake Range, Nevada, Loretta D. Dickson

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alkali basalts on Citadel Mountain form the southern margin of the Lunar Crater Volcanic Field (LCVF) in the central Great Basin, Nevada. Citadel Mountain comprised of a faulted, north tilted section of Tertiary andesite and ash-flow tuff is capped by Pliocene and Quaternary alkali basalt flows that erupted from six major cinder cones. The basalt flows on Citadel Mountain can be divided into two groups (older and younger) based on age and isotopic signatures. The older basalt group is characterized by higher ⁸⁷ Sr/⁸⁶Sr and lower E_Nd and the younger group has lower ⁸⁷Sr/⁸⁶Sr …

The Migration Of Arsenic And Lead In Surface Sediments At Three Kids Mine Henderson, Nevada, Douglas Brian Sims

Publications (WR)

This study focused on the distribution of arsenic and lead in surface sediments at Three Kids Mine in Henderson, Nevada. The mine site encompasses approximately 470 acres of desert and is situated above two developing communities (Lake Las Vegas and Calico Ridge) and the Las Vegas Valley's water source (Lake Mead).

Transport of arsenic and lead appears to have occurred within a limited range in both the eastern and western washes on the eastern and western sides of Three Kids Mine. Concentrations of arsenic range between 20 mg/kg (ppm) and 1130 mg/kg and between 20 mg/kg and 8400 mg/kg for …

A Comparison Study Of Water Well Grouting Materials, Sherry L. Callaway

Masters Theses

To prevent contamination from occurring in water wells, and thereby groundwater, the annulus between the well casing and borehole wall must be sealed with a grout that is capable of maintaining a proper seal. Several factors and properties determine the integrity of the grout and the seal formed by that grout.

A field study discovered limitations in all of the tested grout types. Most grouts were found to vary greatly in thickness surrounding the well casing. Bentonite slurry grouts settled excessively. Cement and bentoni tecement grouts did not adhere to PVC well casing. Bentonite-cement grout fractured. The granulated bentonite was …

Laboratory Comparison Of Trench Design Options For Recovering Spilled Oil, Renuka Fernando

Masters Theses

The research goal was to improve the performance of drainage trenches used to recover spilled oil in the subsurface. Different trench designs were compared in two laboratory experiments. The first laboratory experiment clearly demonstrates that the performance of a oil recovering drainage trench could be improved by replacing the standard gravel pack sand used around the drain pipe with mixtures of teflon and sand. The effectiveness of a downgradient impermeable 'backstop' also was studied in the first experiment.

In experiment two, four trench designs were compared: perforated drain pipe; wire-wrapped horizontal well screen; perforated sheet pile; and gravel fill with …

Lithological And Stratigraphic Analysis Of Glacial Diamictons, Sturgis, Michigan, R. Christopher Gardner

Masters Theses

Seven diamictons are identified in the subsurface glacial drift near Sturgis, Michigan using textural analyses and x-ray diffraction of clay minerals. The clay mineral content is quantified by comparing the 7-A/10- A peak height ratios from x-ray diffraction diffractograms of oriented clay-size particle (<2um) mounts. Two diamictons occur at the base of the drift. Unit 1 is gray , resembling the shale it overlies. The texture of Unit 1 is sandy clay loam to loam and average 7-A/10-A peak height clay mineral ratios of 0.446 ±0.069. Unit 2 is a yellowish-brown diamicton, it overlies Unit 1, and is a sandy loam to loam with average 7-A/10-A clay mineral ratio of 0.657 ±0.151. Diamicton Units 4 and 5 overlie a thick unit of sand and gravel on top of Unit 2. Units 4 and 5 have similar color and texture, however the 7-A/10-A ratios are 1.059 ±0.090 and 0.810 ±0.072 respectively. Unit 6 is a thin diamicton unit, leached of calcite, and x-ray diffraction suggests that there is a range of weathering horzins between borings. Unit 7 is loamy, whereas Unit 8 generally ranges from sandy clay loam to sandy loam with average 7-A/10-A ratios of 0.865 ±0.090 and 1.195 ±0.189.

Vertical Axis Rotation In The Silurian Hills: A Cenozoic Overprint On The Mesozoic U.S. Cordilleran Magmatic Arc, John E. Comstock

University of New Orleans Theses and Dissertations

New, detailed field work in the Silurian hills, southeast of Death Valley, reveals a pattern of a complex Cenozoic brittle fault overprint of rocks containing evidence of at least three episodes of Mesozoic thermal-ductile deformation. The Cenozoic brittle fault overprint of rocks containing evidence of at least three episodes of Mesozoic thermal-ductile formation. The Cenozoic faulting consists of five distinct sets of structures ordered by cross cutting relationships. The oldest, BF1, are fragments of reverse faults trending NW and dipping 45-60 SW. BF2 consist of NW trending, en echelon, sinistral strike-slip faults. BF3 is a conjugate set of N-NE trending …

Stratospheric Loading Of Sulfur From Explosive Volcanic Eruptions, Gregg J. Bluth, William I. Rose, Ian E. Sprod, Arlin J. Krueger

Department of Geological and Mining Engineering and Sciences Publications

This paper is an attempt to measure our understanding of volcano/atmosphere interactions by comparing a box model of potential volcanogenic aerosol production and removal in the stratosphere with the stratospheric aerosol optical depth over the period of 1979 to 1994. Model results and observed data are in good agreement both in magnitude and removal rates for the two largest eruptions, El Chicho´n and Pinatubo. However, the peak of stratospheric optical depth occurs about nine months after the eruptions, four times longer than the model prediction, which is driven by actual SO2 measurements. For smaller eruptions, the observed stratospheric perturbation is …

Geology Newsletter- 1997, Department Of Geology

Geological and Environmental Sciences News

Vol. 1, No. 22

• Dear Alumni and Friends
• Faculty News
• Awards and Scholarships
• Alumni News
• Geology Development and Scholarship Donations
• Advisory Council News

Salinity And Hydrology Of The Mills Lake Catchment, R Ferdowsian, A T. Ryder

Resource management technical reports

The Mills Lake Catchment is located north of the Ongerup-Jerramungup Road, 35 km west of Jerramungup and 10 km north-east of Ongerup. It covers about 23,800 ha of agricultural land that is more than 90% cleared and predominantly cropped. The average annual rainfall of the catchment is about 370 mm. Many low-lying parts of the study area have become salt-affected during recent years. The extent of soil salinity is growing rapidly and it is feared that, without any treatment, more land will become salt-affected.

S K S Splitting Beneath Continental Rift Zones, Stephen S. Gao, Paul M. Davis, Kelly H. Liu, Philip D. Slack, Andrew W. Rigor, Yu A. Zorin, Valentina V. Mordvinova, Vladimir M. Kozhevnikov, Nikolai A. Logatchev

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

We present measurements of S K S splitting at 28 digital seismic stations and 35 analog stations in the Baikal rift zone, Siberia, and adjacent areas, and at 17 stations in the East African Rift in Kenya and compare them with previous measurements from the Rio Grande Rift of North America. Fast directions in the inner region of the Baikal rift zone are distributed in two orthogonal directions, NE and NW, approximately parallel and perpendicular to the NE strike of the rift. In the adjacent Siberian platform and northern Mongolian fold belt, only the rift-orthogonal fast direction is observed. In …

An Ice Shelf Mechanism For Heinrich Layer Production, Christina L. Hulbe

Geology Faculty Publications and Presentations

The effect of an ice shelf in the Labrador Sea on ice-rafted sediment delivery to the glacial North Atlantic is investigated using a finite element numerical model of ice shelf flow. Discharge into the shelf from Hudson Strait creates a thick central core, extending downstream into the shelf, that is flanked by relatively thin ice. Melting at the base of the deep keel would produce cool, fresh water which would rise to refreeze along the keel's flanks. Debris deposited by melting deep central ice could create the Heinrich layers observed in the Labrador Sea while the debris-rich ice protected by …

Field Trip Guide (For The Nebraska Well Drillers Association) Northeastern Nebraska Geology, Sue Olafsen Lackey, Robert F. Diffendal Jr., Raymond R. Burchett, Duane A. Eversoll, Rodney J. Tremblay

Conservation and Survey Division

Field trip guide, for the Nebraska Well Drillers Association, covering northeastern Nebraska geology from September 1997.

Geology Of The Ponca Creek And Keya Paha River Drainage Basins In Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

The geology of the study area has been investigated many times over more than a century. Interested readers are directed to the report by Diffendal and Voorhies (1994), which gives a more detailed overview of the results of the investigations and lists most of the more important reports about the area’s geology.

The names of the sedimentary rock strata and unlithified sediments exposed in and underlying all or parts of the study area are shown in Table V.I. These formations range in age from more than 85 million years to sediments being deposited today by winds, water, and downslope movements …

Geology Of Niobrara State Park, Knox County, Nebraska, And Adjacent Areas, With A Brief History Of The Park, Gavins Point Dam, And Lewis And Clark Lake, Charles A. Flowerday, Robert F. Diffendal Jr., R. L. Skelly, F. G. Ethridge, D. A. Eversoll, David K. Watkins, B. E. Bailey

Conservation and Survey Division

Location

Niobrara State Park is located in northwestern Knox County, Nebraska, just west of the town of Niobrara and on the west side of the Niobrara River. The present park was opened in the summer of 1987. Mostly north of Nebraska Highway 12, the site is hilly with bluffs overlooking the Missouri and Niobrara rivers. Excellent facilities include paved roads, cabins, an outdoor swimming pooi, hiking trails, picnic and camping sites, horseback riding trails, playgrounds, restrooms, a group lodge, and an interpretive shelter. Many vantage points in the park have beautiful views of the lower Niobrara Valley and the middle …

Geologic Evidence Of Historic And Prehistoric Tsunami Inundation At Seaside, Oregon, Brooke K. Fiedorowicz

Dissertations and Theses

Over the past decade, research conducted along the Cascadia subduction zone coast established evidence for coseismic subsidence, liquefaction, and nearfield tsunami deposition. Seaside is a low lying northern Oregon coastal city potentially at risk for nearfield tsunami inundation from a Cascadia earthquake. The 1964 Alaskan farfield tsunami impacted Seaside, and deposits from that event serve as a model for interpreting prehistoric tsunami deposits in the Seaside area. A reconnaissance subsurface study of potential tsunami inundation sites was performed by trenching and gouge coring in the coastal wetlands along the Necanicum River, Neacoxie Creek, drainage to the east of Neacoxie Creek, …

Reservoir Characterization Of Crystal Field And Analysis Of The Tow#1-3 Hd-1 Well, Montcalm County, Michigan, Heidi Wines

Masters Theses

The goal of this project was to characterize the Dundee reservoir of Crystal oil field using the newly drilled Tow #1-3 well data in conjunction with historical well records to evaluate heterogeneity of facies and their controls on oil production.

From the Tow# 1-3 HD-1 well, three major facies were identified in the reservoir. A non-fractured intertidal grainstone facies provides storage of fluids with its uniform permeability and excellent intercrystalline porosity. The supratidal fractured micrites and open marine fractured biomicrites are interbedded with the grainstone facies providing conduits for fluid migration between the facies. Facies are important controls on oil …

Geophysical Characterization Of A Jp-4 (Lnapl) Contaminated Site At The Wurtsmith, Air Force Base, Oscoda, Michigan, Kristina C. Sprietzer

Masters Theses

The detection of hydrocarbon contamination in the subsurface using geophysical techniques has been based on the known physical properties of high electrical resistivities (ρa) (low conductivities). However, geophysical field investigations at uncontrolled spill sites yield measurements of low resistivity (high conductivity). The purpose of this study is to test that in the natural environment some hydrocarbon spills (in the case of LNAPLs), can exhibit changes with time due to biodegradation, from electrically resistive to conductive. Since time is an important factor, this hypothesis was tested at a site where the time when a hydrocarbon release occurred is known and where …

Sediments And Shallow Stratigraphy Of A Portion Of The Continental Shelf Of Southeastern Virginia, Carl H. Hobbs Iii

Reports

A network of high-resolution, seismic-reflection profiles and grab samples of the surficial sediments of the inner continental shelf of southeastern Virginia demonstrate that the Quaternary geology of the region is more complex than indicated by earlier studies. The spatial variability of the surficial sediments depicts active processes, such as outflow from Chesapeake Bay, as well as the underlying geology in outcrops of finer grained sediments near False Cape.

The complexity of the Quaternary geology results from large and small scale fluctuations in sea level. Individual, relatively large-scale, seismostratigraphic units are separated by erosional surfaces formed during the major changes in …

A Bayesian Nonlinear Inversion Of Seismic Body-Wave Attenuation Factors, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

It is a well-known fact that the uncertainties in measuring relative attenuation factors within a local or regional seismic network are usually high, due to noise of different kinds and unrealistic assumptions. Numerical experiments using nine synthetic seismograms, created using t* values ranging from 0.1 to 0.9 sec, reveal that the commonly used spectral ratio method is strongly affected by the selection of data processing parameters such as width of the spectral smoothing window, reference station, and so on. The numerical experiments demonstrate that a Bayesian nonlinear inversion approach that directly matches the spectra is better at finding the correct …

Systematics Of Stable Isotopes And Radionuclides In Precipitation At Kalamazoo, Michigan, Usa, Madhav V. Machavaram

Dissertations

Precipitation samples were collected at Kalamazoo from June 1992 to March 1995. The samples were analyzed for their 8D and 8lgO values. The 5D - 5I80 relationship is comparable to that of Meteoric Water Line (MWL). The monthly mean isotopic values in precipitation exhibited strong seasonality, being higher in summer and lower in winter months. This behavior is apparently a direct consequence of the temperature effect on isotope fractionation.

The summer precipitation at Kalamazoo is derived predominantly from the water vapor originated in the Gulf of Mexico. A box model calculation showed that a Rayleigh type distillation with Gulf moisture …

Long Dormancy, Low Slip Rate, And Similar Slip‐Per‐Event For The Emerson Fault, Eastern California Shear Zone, Charles M. Rubin, Kerry Sieh

All Faculty Scholarship for the College of the Sciences

Excavations in a playa along the 1992 rupture of the Emerson fault reveal evidence of two paleoseismic events, with only one large prehistoric rupture in the past 15 millennia. Accelerator mass spectrometer radiocarbon ages of charcoal from playa sediments and from fault‐scarp colluvium directly beneath the playa beds indicate that the last large prehistoric slip event occurred about 9000 ka. Trench‐wall exposures revealed clear evidence of at least one pre‐9 ka rupture at the playa site. The event horizon of this earthquake is between two pedogenic carbonate layers that have radiocarbon ages of 14.8 ka and 24.1 ka, implying that …

Microanalytical Investigations Of Gold-Bearing Rocks From The An Najadi Region In Saudi Arabia, Nazrul I. Khandaker, M. Ahmed, M. M. Hariri, M. A. Garwan, K. R. Khan, M. M. Al-Ohali

Publications and Research

The Proton Induced X-ray Emission technique with a scanning microbeam (micro-PIXE) and Scanning Electron Microscopy (SEM) were employed to study gold-bearing rocks from the An Najadi and adjacent regions situated within the exposed northeastern part of the Arabian Shield. These microanalytical investigations, together with routine petrological and ore microscopic studies, demonstrated the presence of important partitioning of major minerals and trace elements in several samples. These measurements also revealed microstructural features including brecciation within quartz grains and metal concentrations within these fracture-controlled micro-conduits. Results showed promise in terms of using distinctive geochemical signatures for ore body recognition. Of particular interest …

Detection Of Volcanic Ash Clouds From Nimbus 7/Total Ozone Mapping Spectrometer, C. J. Seftor, N. C. Hsu, J. R. Herman, P. K. Bhartia, O. Torres, William I. Rose, David J. Schneider, N. Krotkov

Department of Geological and Mining Engineering and Sciences Publications

Measured radiances from the Version 7 reprocessing of the Nimbus 7/total ozone mapping spectrometer (TOMS) 340- and 380-nm channels are used to detect absorbing particulates injected into the atmosphere after the El Chichon eruption on April 4, 1982. It is shown that while the single-channel reflectivity determined from the 380-nm channel is able to detect clouds and haze composed of nonabsorbing aerosols, the spectral contrast between the 340- and 380-nm channels is sensitive to absorbing particulates such as volcanic ash, desert dust, or smoke from biomass burning. In this paper the spectral contrast between these two channels is used to …

Researchers Pool Knowledge About Antarctic Dry Valleys, Andrew G. Fountain, Sarah Spaulding

Geology Faculty Publications and Presentations

Most of us think of ice when we think of the Antarctic, and rightly so, considering that only 5% of it is ice-free. Dry valleys--the ice-free areas--have sandy, rocky valley floors, ice-covered lakes, and streams that flow only two months of the year. The McMurdo Dry Valleys (78øS 163øE) are the largest of these regions.

Oil And Gas Map Of The Tompkinsville 30 X 60 Minute Quadrangle, Kentucky, Brandon C. Nuttall

Map and Chart--KGS

No abstract provided.

Concentrations And Isotope Ratios Of Dissolved Inorganic Carbon In Denitrifying Environments, C. Nascimento, Eliot A. Atekwana, R. V. Krishnamurthy

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

We measured the concentration and isotope ratio of dissolved inorganic carbon (DIC) in groundwater associated with denitrification (C_org + NO₃^- = CO₂ + N₂) in an agriculturally impacted site in southwestern Michigan. Samples with the lowest nitrate levels also had low dissolved oxygen content and were more depleted in δ¹³C than background groundwater. All the samples had DIC concentrations in excess of titratable alkalinity. The magnitude of this DIC in excess of alkalinity correlated with a decreasing δ¹³C attesting to the presence of CO₂ derived from organic carbon. Carbon …