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Lewis And Clark And The Geology Of Nebraska And Parts Of Adjacent States, Robert F. Diffendal Jr., Anne P. Diffendal

School of Natural Resources: Faculty Publications

Meriwether Lewis and William Clark undertook their journey with the Corps of Discovery in 1804–1806 in order to explore the area that the United States had purchased from France in 1803. Then known as Louisiana, this region included almost everything west of the Mississippi to the continental divide (illustrated below). In order to find the best route across the continent, President Thomas Jefferson charged Lewis to follow the Missouri River to its headwaters and then locate rivers flowing down the west side of the Rocky Mountains to the Columbia River and into the Pacific Ocean. Jefferson's written instructions further specified …

Lewis And Clark And The Geology Of The Great Plains, Robert F. Diffendal Jr., Anne P. Diffendal

School of Natural Resources: Faculty Publications

Meriwether Lewis and William Clark undertook their journey with the Corps of Discovery in 1804-1806 in order to explore the area that the United States had purchased from France in 1803. Then known as Louisiana, this region included almost everything west of the Mississippi to the continental divide. In order to find the best route across the continent, President Thomas Jefferson charged Lewis with following the Missouri River to its headwaters and then locating rivers flowing down the west side of the Rocky Mountains to the Columbia River and into the Pacific Ocean. Jefferson's written instructions further specified that the …

Current Perspectives On Energy And Mass Fluxes In Volcanic Arcs, William Leeman, Jon Davidson, Tobias Fischer, Anita Grunder, Mark Reagan, Martin J. Streck

Geology Faculty Publications and Presentations

Volcanoes of the Pacific Ring of Fire and other convergent margins worldwide are familiar manifestations of nature's energy, account for about 25% of global volcanic outputs, dominate volcanic gas emissions to the atmosphere, and pose significant physical threats to a large human population. Yet the processes behind this prolific activity remain poorly understood.

An international "State of the Arc" (SOTA) conference was held in August on the slopes of Mt. Hood, Oregon, to address current views on the energy and mass fluxes in volcanic arcs. This meeting brought together some 90 leading experts and students of subduction zones and their …

Field-Scale Estimation Of Volumetric Water Content Using Ground-Penetrating Radar Ground Wave Techniques, Katherine R. Grote, Susan Sharpless Hubbard, Yoram N. Rubin

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Ground-penetrating radar (GPR) ground wave techniques were applied to estimate soil water content in the uppermost ∼10 cm of a 3 acre California vineyard several times over 1 year. We collected densely spaced GPR travel time measurements using 900 and 450 MHz antennas and analyzed these data to estimate water content. The spatial distribution of water content across the vineyard did not change significantly with time, although the absolute water content values varied seasonally and with irrigation. The GPR estimates of water content were compared to gravimetric water content, time domain reflectometry, and soil texture measurements. The comparisons of GPR-derived …

Mantle Layering Across Central South America, Kelly H. Liu, Stephen S. Gao, Paul G. Silver, Yongkai K. Zhang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Imaging of seismic velocity discontinuities along a 3000 km profile across central South America at 20°S suggests that the depth variations of the 410-km (d410) and 660-km (d660) discontinuities are closely associated with the high-velocity Nazca slab and juxtaposed low-velocity oceanic mantle beneath the slab. The mantle transition zone thickness ranges from 220 km in the oceanic mantle to 270 km in a 600-km-wide area occupied by the deflected Nazca slab. The slab deflection has also been suggested by previous studies of seismic tomography and seismicity. This 50 km difference in the thickness corresponds to a lateral temperature variation of …

Sulfide Mineralization In Deep-Water Marine Sediments Related To Methane Transport, Methane Consumption, And Methane Gas Hydrates, Matthew K. Thompson, Walter S. Borowski, Charles K. Paull, William Ussler Iii

EKU Faculty and Staff Scholarship

Patterns of sulfide sulfur concentration and sulfur isotopic composition (d³⁴S) are perhaps related to upward methane transport, especially in sediments underlain by methane gas hydrate deposits. Increased methane delivery augments the affect of anaerobic methane oxidation (AMO) occurring at the sulfate-methane interface (SMI). Sulfate and methane co-consumption results in production of dissolved sulfide at the interface that is eventually sequestered within sulfide minerals (elemental sulfur, iron monosulfide, pyrite).

We examine the sediments of two piston cores collected over the Blake Ridge gas hydrate deposits (offshore southeastern North America) by extracting total sedimentary sulfide using chromium reduction. We use …

Using Cesium 137 To Understand Recent In Cave Sedimentation In The Tongass National Forest, Southeast Alaska, William Curry

Masters Theses & Specialist Projects

Removal of vegetation and subsequent erosion in karst regions such as central Kentucky or southeastern Alaska often leads to increased sedimentation in karst features such as caves and dolines. This sedimentation can impact the ground water by altering flow paths and the bio-geochemistry of the karst aquifer itself. Various methodologies have been used to obtain quantitative erosion and sedimentation rates for surface areas in karst and non-karst settings, but few quantitative studies have taken place in caves. The purpose of this study is to examine the effects of timber harvesting and development upon the caves and karst of southeastern Alaska …

Ancient Maize From Chacoan Great Houses: Where Was It Grown?, Larry Benson, Linda Cordell, Kirk Vincent, Howard E. Taylor, John Stein, G. Lang Farmer, U.S. Geological Survey

United States Geological Survey: Staff Publications

In this article, we compare chemical (⁸⁷Sr/⁸⁶Sr and elemental) analyses of archaeological maize from dated contexts within Pueblo Bonito, Chaco Canyon, New Mexico, to potential agricultural sites on the periphery of the San Juan Basin. The oldest maize analyzed from Pueblo Bonito probably was grown in an area located 80 km to the west at the base of the Chuska Mountains. The youngest maize came from the San Juan or Animas river floodplains 90 km to the north. This article demonstrates that maize, a dietary staple of southwestern Native Americans, was transported over considerable distances in …

Integrated Hydrologic And Hydrochemical Observations Of Hidden Creek Lake Jökulhlaups, Kennicott Glacier, Alaska, Suzanne P. Anderson, Joseph S. Walder, Robert S. Anderson, Erin R. Kraal, Michelle Cunico, Andrew G. Fountain, Dennis C. Trabant

Geology Faculty Publications and Presentations

Hidden Creek Lake (HCL), an ice-marginal lake impounded by Kennicott Glacier, Wrangell Mountains, Alaska, fills annually to ~20 to 30 x ~10⁶ m³ and then drains subglacially within 2 to 3 days. During the 1999 and 2000 jökulhlaups, we carried out a series of planned observations around the lake and in the Kennicott River, which drains the glacier. Approximately 20% of the lake volume was contained within a subglacial water ‘‘wedge’’ beneath the ice dam. The entire volume of the lake drains through the wedge; hydraulic head loss through this constriction may be responsible for the fairly symmetrical shape of …

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 …

Geogram 2003, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Mri: Acquisition Of A Modern Electron Microprobe At The University Of Maine, Charles V. Guidotti

University of Maine Office of Research Administration: Grant Reports

This award, made through the Major Research Instrumentation (MRI) Program, provides support for the acquisition of a state-of-the-art electron microprobe (EMP) for the microchemical characterization of geological materials. A new EMP will replace an aging (vintage 1981) ARL SEMQ in the Department of Geological Sciences at the University of Maine. The instrument will facilitate research on a range of topics in metamorphic petrology including, the speciation of Fe and distribution of OH- in metapelites, and light element (i.e. Li, B, Be) partitioning in granulite facies rocks. Research in paleoclimatology will also be enhanced by this instrument. The probe will be …

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

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: 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: 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: 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

Energy Field Tour 2003 (August 11-16)

10 pages (includes color illustrations and maps).

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

Energy Field Tour 2003 (August 11-16)

4 pages.

Contains references.

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

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 …

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 …

Characterizing Fracture Distribution In Layered Rocks Using Geographic Information System-Based Techniques, Kajari Ghosh

FIU Electronic Theses and Dissertations

Fractures are discrete planar features that are heterogeneously distributed throughout the earth's upper crust. Methods commonly used to quantify fracture populations typically yield singular values/indexes for the attribute of interest. These values are useful in characterizing the bulk properties of a fracture population, but are unable to address the inherent spatial heterogeneities of the fracture network.

This study explores techniques to map fractures and capture the spatial heterogeneity of fracture networks within a Geographic Information System (GIS). The study was performed on exposures of the intensely fractured Monterey Formation in Santa Barbara, California. Results of the GIS-based spatial analysis provide …

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

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

Conservation and Survey Division

No abstract provided.

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 …

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.

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

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 …