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Full-Text Articles in Geology

Longbase Laser Strainmeter Measurements From The South Ramp Of The Yucca Mountain Facility, Frank K. Wyatt, Duncan C. Agnew, James N. Brune, Amy J. Smiecinski Oct 2003

Longbase Laser Strainmeter Measurements From The South Ramp Of The Yucca Mountain Facility, Frank K. Wyatt, Duncan C. Agnew, James N. Brune, Amy J. Smiecinski

Publications (YM)

Under subcontract (DOE/UCCSN DE-FC28-98NV12081, Task 7) from the Seismological Laboratory of the University of Nevada-Reno, the University of California, San Diego (UCSD), has designed, installed, and operated a laser strainmeter (LSM) in the Exploratory Studies Facility (ESF) at Yucca Mountain, Nevada. This instrument provides precise deformation monitoring of the (proposed) repository block. This document describes the history of the installation, outlines the principles of operation of the system, documents the integral recording and control system and file formats used, and provides information on how QA has been implemented, with the aim of being a self-contained description which could be used …


Dissolved Humic Substances: Characterization Of Their Sorption Onto Iron Hydroxide Aluminum Hydroxide Kaolinite And Smectite, Sarah E. Diebel Oct 2003

Dissolved Humic Substances: Characterization Of Their Sorption Onto Iron Hydroxide Aluminum Hydroxide Kaolinite And Smectite, Sarah E. Diebel

OES Theses and Dissertations

Humic (HA) and fulvic (FA) acids participate in many geochemical processes and the mechanisms of their sorption to colloidal surfaces are numerous, indicating these substances are complex and heterogeneous. The current study focuses on the interactions of the Fe hydroxide (FE), Al hydroxide, Kaolinite (KA) and Smectite (SM) and these naturally occurring organic acids using Fourier Transform Infrared Spectroscopy (FTIR) and DOC analysis at pH 4. FTIR was used for the initial functional group characterization, as well as the comparison of before and after adsorption spectra of the HA and FA. DOC examined the amounts of HA and FA adsorbed …


A Stochastic Sediment Delivery Model For A Steep Mediterranean Landscape, Emmanuel Gabet, Thomas Dunne Sep 2003

A Stochastic Sediment Delivery Model For A Steep Mediterranean Landscape, Emmanuel Gabet, Thomas Dunne

Faculty Publications

It is a truism in geomorphology that climatic events operate on a landscape to drive sediment transport processes, yet few investigations have formally linked climate and terrain characteristics with geomorphological processes. In this study, we incorporate sediment transport equations derived from fieldwork into a computer model that predicts the delivery of sediment from hillslopes in a steep Mediterranean landscape near Santa Barbara, California. The sediment transport equations are driven by rainstorms and fires that are stochastically generated from probability distributions. The model is used to compare the rates and processes of sediment delivery under two vegetation types: coastal sage scrub …


Great Plains Workshop Held To Prepare For Usarray Deployment, Mary S. Hubbard, S. S. Gao, K. H. Liu, K. E. Nicolaysen, C. G. Oviatt Aug 2003

Great Plains Workshop Held To Prepare For Usarray Deployment, Mary S. Hubbard, S. S. Gao, K. H. Liu, K. E. Nicolaysen, C. G. Oviatt

Geosciences Faculty Publications

Relative to most parts of North America, the Great Plains region, which is bordered by the Rocky Mountain Front on the west and the Mississippi River on the east, has been understudied in terms of the structure, formation, and evolution of the underlying crust, mantle, and core. The anticipated arrival of the USArray portable seismic stations, which will cover the entire United States regardless of surface geology and tectonic activities, and the deployment of the accompanying flexible array stations and the permanent seismic stations in this area, will fill this gap and address numerous problems related to the structure and …


Day 3. Wednesday, August 13, 2003: Oil Shale, University Of Colorado Boulder. Natural Resources Law Center Aug 2003

Day 3. Wednesday, August 13, 2003: Oil Shale, University Of Colorado Boulder. Natural Resources Law Center

Energy Field Tour 2003 (August 11-16)

8 pages.

Contains references.


Day 3. Wednesday, August 13, 2003: Travel To Grand Junction, University Of Colorado Boulder. Natural Resources Law Center Aug 2003

Day 3. Wednesday, August 13, 2003: Travel To Grand Junction, University Of Colorado Boulder. Natural Resources Law Center

Energy Field Tour 2003 (August 11-16)

5 pages (includes color illustration and map).

Contains references.


Day 3. Wednesday, August 13, 2003: Clifford Duncan, Ute Tribe, Clifford Duncan Aug 2003

Day 3. Wednesday, August 13, 2003: Clifford Duncan, Ute Tribe, Clifford Duncan

Energy Field Tour 2003 (August 11-16)

4 pages.

Contains references.


Day 3. Wednesday, August 13, 2003: Lighthawk Flyover, University Of Colorado Boulder. Natural Resources Law Center Aug 2003

Day 3. Wednesday, August 13, 2003: Lighthawk Flyover, University Of Colorado Boulder. Natural Resources Law Center

Energy Field Tour 2003 (August 11-16)

11 pages (includes some color illustrations and maps).

Contains references.


Day 3. Wednesday, August 13, 2003: Coalbed Methane Development, University Of Colorado Boulder. Natural Resources Law Center Aug 2003

Day 3. Wednesday, August 13, 2003: Coalbed Methane Development, University Of Colorado Boulder. Natural Resources Law Center

Energy Field Tour 2003 (August 11-16)

10 pages (includes color illustrations and maps).


Day 2. Tuesday, August 12, 2003: Delta Montrose Energy, University Of Colorado Boulder. Natural Resources Law Center Aug 2003

Day 2. Tuesday, August 12, 2003: Delta Montrose Energy, University Of Colorado Boulder. Natural Resources Law Center

Energy Field Tour 2003 (August 11-16)

1 page.

Contains references.


Agenda: Energy Field Tour 2003, University Of Colorado Boulder. Natural Resources Law Center Aug 2003

Agenda: Energy Field Tour 2003, University Of Colorado Boulder. Natural Resources Law Center

Energy Field Tour 2003 (August 11-16)

Congressional staff tour held August 11-16, 2003

Summary: Binder of assorted articles, maps, brochures and other materials prepared for participants of the tour

Contents:

MONDAY, AUGUST 11, 2003: BLUE SPRUCE PEAKER PLANT: University of Colorado Natural Resources Law Center : congressional staff tour of Blue Spruce Energy Center / Peggy Duxbury -- 'Power Struggle', National Journal, June 27, 2003 / Margaret Kritz -- 'Calpine's Blue Spruce Energy Center begins commercial operation', Calpine press release, April 17, 2003 -- NATIONAL RENEWABLE ENERGY LAB: NREL at a glance -- NREL technologies -- SHOSHONE HYDROELECTRIC PLANT: 'River District Board supports spring Shoshone call …


Application Of Geochemical Fingerprinting And Isotopes To Identity Landfill Gas Impacts To Groundwater, Eric E. Wallis Aug 2003

Application Of Geochemical Fingerprinting And Isotopes To Identity Landfill Gas Impacts To Groundwater, Eric E. Wallis

Masters Theses

Volatile organic compounds (VOCs) are detected in two groundwater monitoring wells (MW-60 and MW-62S) located along the northern, downgradient property line of the McGill Road Landfill (MRL) in Jackson, Michigan. Potential on-site sources for groundwater impact are two distinct landfill units at the MRL. Leachate chemistry suggested that landfill leachate was not the source of VOCs detected in groundwater. A potential source for VOCs was landfill gas. Sources of landfill gas in the vicinity of the impacted wells included the distinct MRL landfill units as well as the old Jackson County Landfill (JCL), located hydraulically downgradient from the impacted wells. …


Sediment Distribution And Composition On The Shallow Water Carbonate Basin Of The Zanzibar Channel, Yw Shaghude Jul 2003

Sediment Distribution And Composition On The Shallow Water Carbonate Basin Of The Zanzibar Channel, Yw Shaghude

Tanzania Journal of Science

Sediments of the shallow water carbonate basin in Zanzibar channel were investigated for composition and grain size distribution. The surface sediment composition was dominated by carbonate sands (with CaCO3 > 30%), except in the area adjacent to mainland coastline and a thin lobe which projects from Ruvu River to the middle of the channel. Mean grain size distribution closely resembles that of the carbonate content, where Tidally Dominated Reef Platform Sediments (TDRPS) located east of the Zanzibar channel were characterised by medium to coarse sands and the siliciclastic sediments adjacent to the mainland were characterised by fine sand. The TDRPS are …


Tectonic And Sedimentary Evolution Of The Coastal Basin Of Tanzania During The Mesozoic Times, S Kapilima Jul 2003

Tectonic And Sedimentary Evolution Of The Coastal Basin Of Tanzania During The Mesozoic Times, S Kapilima

Tanzania Journal of Science

The present paper reviews and updates the stratigraphy and tectonic evolution of the coastal basin of Tanzania during the Mesozoic times based on the interpretation of existing palaeontological and stratigraphical information and supplemented by recent fieldwork investigations by the author. Tectonic events largely controlled the evolution of the coastal basin of Tanzania and the Indian Ocean. These included the Karoo rifting during Permo-Triassic, the break up of the Gondwana Supercontinent, which started with rifting in the Triassic period, the opening of the Somali basin in the Middle Jurassic, and the Cenozoic rifting along the East African rift system. The Karoo …


Levels Of Pesticide Residues In Water, Soil And Sediments From Southern Lake Victoria And Its Basin, Leonia Henry, Michale A Kishimba Jul 2003

Levels Of Pesticide Residues In Water, Soil And Sediments From Southern Lake Victoria And Its Basin, Leonia Henry, Michale A Kishimba

Tanzania Journal of Science

Water, sediment and soil samples collected from Southern Lake Victoria and its basin were analysed for 76 organochlorine, organophosphorous, carbamate and pyrethroid pesticide residues. The samples were collected from sampling stations in nine districts on the Tanzanian side of the lake, namely Mwanza, Sengerema, Geita, Ngudu, Misungwi, Magu, Bunda, Tarime and Musoma Districts. DDT and HCH residues were the only detected pesticides. The concentration of total DDT was up to 1.6 mg/L in water, 600 mg/kg dry mass in sediments and 20 mg/kg dry mass in soil. The concentration of total HCHs were up to 0.2 mg/L in water, 132 …


High Altitude Himalayan Climate Inferred From Glacial Ice Flux, Joel T. Harper, Neil Humphrey Jul 2003

High Altitude Himalayan Climate Inferred From Glacial Ice Flux, Joel T. Harper, Neil Humphrey

Geosciences Faculty Publications

Glaciological processes are modeled to investigate precipitation patterns and the resulting mass flux of snow and ice across Himalayan topography. Our model tracks the accumulation and ablation of snow and ice and the transport of snow and ice across the topography by glacier motion. We investigate high elevation precipitation on the Annapurna Massif by comparing the existing ice cover with model-simulated glaciers produced by a suite of different precipitation scenarios. Our results suggest that precipitation reaches a maximum level well below the elevation of the highest peaks. Further, essentially no snow accumulates on the topography above an elevation of 6200–6300 …


Exploring Links Between Physical And Probabilistic Models Of Volcanic Eruptions: The Soufriere Hills Volcano, Montserrat, Charles B. Connor, R. S. J. Sparks, R. M. Mason, Costanza Bonadonna, S. R. Young Jul 2003

Exploring Links Between Physical And Probabilistic Models Of Volcanic Eruptions: The Soufriere Hills Volcano, Montserrat, Charles B. Connor, R. S. J. Sparks, R. M. Mason, Costanza Bonadonna, S. R. Young

Geology Faculty Publications

Probabilistic methods play an increasingly important role in volcanic hazards forecasts. Here we show that a probability distribution characterized by competing processes provides an excellent statistical fit (>99% confidence) to repose intervals between 75 vulcanian explosions of Soufrière Hills Volcano, Montserrat in September–October, 1997. The excellent fit is explained by a physical model in which there are competing processes operating in the upper volcano conduit on different time scales: pressurization due to rheological stiffening and gas exsolution, and depressurization due to development of permeability and gas escape. Our experience with the Soufrière Hills Volcano eruption sequence suggests that volcanic …


Hydrogeologic Principles Useful In Predicting The Effects Of Stream Flow Alterations On Shallow Groundwater And Associated Riparian Vegetation, Mark Cable Rains Jul 2003

Hydrogeologic Principles Useful In Predicting The Effects Of Stream Flow Alterations On Shallow Groundwater And Associated Riparian Vegetation, Mark Cable Rains

Geology Faculty Publications

Numerous studies have shown that stream water and shallow groundwater are tightly linked in alluvial settings, and that changes in stream stage are propagated rapidly across alluvial aquifers (Castro and Hornberger 1991, Sophocleous 1991). Thus, many researchers have assumed that stream stages approximate water tables in alluvial aquifers (Auble et al. 1994, Stromberg and Patten 1996). This assumption is valid in some cases but invalid in other cases, particularly in arid basin terrain and more humid mountain terrain. Even when this assumption is valid, this relationship only implies correlation and not causation so the potential effects of stream flow alterations …


History, Geology And Water In The Lower Platte River Valley In Eastern Nebraska, Dave Gosselin, Marv Carlson, Matt Joeckel Jun 2003

History, Geology And Water In The Lower Platte River Valley In Eastern Nebraska, Dave Gosselin, Marv Carlson, Matt Joeckel

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Southeast Nebraska Geology: Field Trip 3, Roger K. Pabian, Robert F. Diffendal, Jr. Jr., Darwin R. Boardman Ii Jun 2003

Southeast Nebraska Geology: Field Trip 3, Roger K. Pabian, Robert F. Diffendal, Jr. Jr., Darwin R. Boardman Ii

Robert F. Diffendal, Jr., Publications

The purpose of this trip is to familiarize you with the latest Pennsylvanian and earliest Permian rocks that are exposed in extreme southeastern Nebraska. You will see eight exposures of these rocks and will have ample opportunity to collect lithologic samples, as well as samples for both macro- and micro-fossils. The stops have been selected to show you examples of several different environments that existed in southeastern Nebraska in the late Paleozoic. These include subaerial deposits with paleosols, nearshore and offshore marine clastic and carbonate sequences. Each stop is covered in detail in the handouts that have been furnished to …


Ashfall Historic Park: Field Trip 5, Robert F. Diffendal Jr. Jun 2003

Ashfall Historic Park: Field Trip 5, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Ashfall Fossill Beds: A State Historical Park. Brochure. Nebraska Game and Parks Commission and University of Nebraska State Museum

Research Reports, 1978. Projects: A Miocene Rhinoceros Herd Buried in Volcanic Ash. Grant Recipient: Michael R. Voorhies, Division of Vertebrate Paleontology, University of Nebraska State Museum, Lincoln, Nebraska.

Geologic Framework of the Niobrara River Drainage Basin and Adjacent Areas in South Dakota Generally East of the 100th Meridian West Longitude and West of the Missouri River Robert F. Diffendal, Jr. and Michael R. Voorhies. Nebraska Geological Survey Report of Investigations, number 9.


Morphological Biosignatures And The Search For Life On Mars, Sherry L. Cady, Jack D. Farmer, John P. Grotzinger, J. William Schopf, Andrew Steele Jun 2003

Morphological Biosignatures And The Search For Life On Mars, Sherry L. Cady, Jack D. Farmer, John P. Grotzinger, J. William Schopf, Andrew Steele

Geology Faculty Publications and Presentations

This report provides a rationale for the advances in instrumentation and understanding needed to assess claims of ancient and extraterrestrial life made on the basis of morphological biosignatures. Morphological biosignatures consist of bona fide microbial fossils as well as microbially influenced sedimentary structures. To be recognized as evidence of life, microbial fossils must contain chemical and structural attributes uniquely indicative of microbial cells or cellular or extracellular processes. When combined with various research strategies, high-resolution instruments can reveal such attributes and elucidate how morphological fossils form and become altered, thereby improving the ability to recognize them in the geological record …


Stratigraphy Of Lake Michigan Lobe Deposits In Van Buren County, Michigan, Steven P. Beukema Jun 2003

Stratigraphy Of Lake Michigan Lobe Deposits In Van Buren County, Michigan, Steven P. Beukema

Masters Theses

The surficial glacial deposits and landforms of Van Buren County were recently mapped at a 1:24,000 scale as part of a STATEMAP project. Several borings were drilled to supplement the surface data. Six of these borings were characterized in detail by means of gamma ray logging, textural analysis, and X-ray diffraction of the clay-sized fraction of the diamicton units.

Results from this study reveal two diamicton units at stratigraphically distinct positions that can be correlated across the county and that are separated by a thick sequence of lacustrine sediments. Correlation of diamicton and lacustrine units was accomplished by analyzing several …


Investigating The Geoelectrical Response Of Hydrocarbon Contamination Undergoing Biodegradation, D. Dale Werkema, Estella A. Atekwana, Anthony L. Endres, William August Sauck, Daniel P. Cassidy Jun 2003

Investigating The Geoelectrical Response Of Hydrocarbon Contamination Undergoing Biodegradation, D. Dale Werkema, Estella A. Atekwana, Anthony L. Endres, William August Sauck, Daniel P. Cassidy

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

A newly proposed geoelectrical model for hydrocarbon contaminated sites predicts high conductivities coincident with the contaminated zone as opposed to the traditionally accepted low conductivity. The model attributes the high conductivities to mineral weathering resulting from byproducts of microbial redox processes. To evaluate this conductive model, in situ vertical conductivity measurements were acquired from a light non-aqueous phase liquid (LNAPL) contaminated site. The results showed high conductivities coincident with the zone of contamination and within the smear zone influenced by seasonal water table fluctuations. We infer this zone as an active zone of biodegradation and suggest significant microbial degradation under …


Melting Processes And Fluid And Sediment Transport Rates Along The Alaska-Aleutian Arc From An Integrated U-Th-Ra-Be Isotope Study, Rhiannon George, Simon Turner, Chris Hawkesworth, Julie Morris, Chris Nye, Jeffrey G. Ryan, Shu-Hui Zheng May 2003

Melting Processes And Fluid And Sediment Transport Rates Along The Alaska-Aleutian Arc From An Integrated U-Th-Ra-Be Isotope Study, Rhiannon George, Simon Turner, Chris Hawkesworth, Julie Morris, Chris Nye, Jeffrey G. Ryan, Shu-Hui Zheng

Geology Faculty Publications

A comprehensive data set for young lavas erupted along the Alaska-Aleutian arc is used to examine how fluid and sediment transport rates and melting processes vary in response to systematic changes in subduction rate and dip along the arc and across the ocean-continent boundary. Positive correlations between convergence rate, volcano volume, and 238U excesses suggest that magmatic output is closely linked to the size of the fluid flux which occurred <10 kyr prior to eruption. Sediment-sensitive tracers like Th/Nb, Ce/Ce*, and 10Be/9Be also increase with convergence rate. However, the inferred 10Be/9Be ratio of this component is low relative to that in the incoming sediments, …


Mitigation, Monitoring, And Geomorphology Related To Gully Erosion Of Archaeological Sites In Grand Canyon, Paul A. Petersen May 2003

Mitigation, Monitoring, And Geomorphology Related To Gully Erosion Of Archaeological Sites In Grand Canyon, Paul A. Petersen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Gully erosion has been damaging archaeological sites in Grand Canyon during the last several decades, and there is a need to protect these features through mitigation, monitoring, and better geomorphic understanding. The purpose of this study was to assess the effectiveness of erosion-control structures, determine the accuracy and utility of aerial photogrammetry for monitoring gullies, and understand the geomorphology of the erosion. We performed total-station surveys and other data collection during February and October, 2002, at nine study sites in eastern and western Grand Canyon.

Erosion-control structures are more prone to be damaged by flow when they are placed in …


Evaluation Of Chela Formation In Kambala-Livuite Area, Southern Block 0, Cabinda, Angola, Alba B. Bias Dos Santos May 2003

Evaluation Of Chela Formation In Kambala-Livuite Area, Southern Block 0, Cabinda, Angola, Alba B. Bias Dos Santos

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The abundance of good reservoir and source rocks offshore Cabinda, Angola, makes the area an attractive and successful hydrocarbon province. Block 0, offshore Cabinda, lies in the Lower Congo basin along the western coast of Africa. The stratigraphy of Block 0 consists of two major oil-rich sequences: the rift sequence (primarily lacustrine) and the post-rift sequence (primarily marine). These are separated by a thick section of evaporites, and thus are referred to as the pre-salt sequence and post-salt sequence, respectively.

The Chela Formation, mid-Aptian in age, was deposited before the salt. It consists of sandstones and conglomerates locally interbedded with …


Quaternary Geology And Landscape Evolution Of Eastern Grand Canyon, Arizona, Matt D. Anders May 2003

Quaternary Geology And Landscape Evolution Of Eastern Grand Canyon, Arizona, Matt D. Anders

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tectonics and drainage evolution are controlling overall landscape incision in eastern Grand Canyon. Superimposed on downcutting are dynamic responses of hillslopes, tributary streams, and the Colorado River to glacial-interglacial climate cycles. Five tributary stream fill terraces have been identified, and luminescence dating indicates aggradation was occurring 50- 34 ka {S3), 12-7 ka (S2), and 5-3.5 ka (S1). Seven Colorado River fill terraces have been identified, and luminescence and U-series dating indicate deposition was occurring 343-322 ka (M5), 151-118 ka (M4), and 71-64 ka (M3).

Aggradation by the Colorado River in eastern Grand Canyon begins during glacial advances and continues into …


From The Rim To The River: The Geomorphology Of Debris Flows In The Green River Canyons Of Dinosaur National Monument, Colorado And Utah, Isaac J. Larsen May 2003

From The Rim To The River: The Geomorphology Of Debris Flows In The Green River Canyons Of Dinosaur National Monument, Colorado And Utah, Isaac J. Larsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Green River canyons of the eastern Uinta Mountains have experienced a 5-year period of high debris flow activity. Catchment factors were studied in watersheds and on debris fans with recent debris flows, leading to the development of a conceptual framework of the hillslope and debris flow processes that deliver sediment to the Green River. Two recent fan deposits were monitored to determine the magnitude and processes of reworking that occur during mainstem floods of varying magnitude.

The dominant debris flow initiation mechanism, termed the firehose effect, occurs when overland flow generated on bedrock slopes cascades down steep cliffs and …


Characteristics, Evolution, And Lateral Variation Of Lower Cretaceous Supradetachment Basins In The Daqing Shan, Inner Mongolia, China, Adrian K. Berry May 2003

Characteristics, Evolution, And Lateral Variation Of Lower Cretaceous Supradetachment Basins In The Daqing Shan, Inner Mongolia, China, Adrian K. Berry

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lower Cretaceous basins associated with the Hohhot detachment in the Daqing Shan of Inner Mongolia, China, allow us to better understand the tectonic evolution of extensional basins formed in association with detachment faulting and metamorphic core complex formation. The six basins, informally named N1, N2, S1, S2, S3, and S4, are located in different structural settings, or depozones, throughout the detachment-metamorphic core complex setting, and although all basins are consistent with previously proposed models for supradetachment basin sedimentation, second-order variability in sedimentary style is exerted by these distinct structural settings. The basins are composed of coarse, predominantly footwall derived, conglomerate …