Geology Commons^™

Arctic Ice Export Events And Their Potential Impact On Global Climate During The Late Pleistocene, Dennis A. Darby, Jens F. Bischof, Robert F. Spielhagen, Steven A. Marshall, Stephen W. Herman

OES Faculty Publications

Ice sheets in the North American Arctic and, to a lesser extent, those in northern Eurasia calved large quantities of icebergs that drifted through Fram Strait into the Greenland Sea several times during the late Pleistocene. These icebergs deposited Fe oxide grains (45-250 mum) and coarse lithic clasts >250 mum matched to specific circum-Arctic sources. Four massive Arctic iceberg export events are identified from the Laurentide and the Innuitian ice sheets, between 14 and 34 ka (calendar years) in a sediment core from Fram Strait. These relatively short duration (<1-4 kyr) events contain 3-5 times the background levels of Fe oxide grains. They began suddenly, as indicated by a steep rise in the number of grains matched to an ice sheet source, suggesting rapid purges of ice through Fram Strait, due perhaps to collapse of ice sheets. The larger events from the northwestern Laurentide ice sheet are preceded by events from the Innuitian ice sheet. Despite the chronological uncertainties, the Arctic export events appear to occur prior to Heinrich events.

High Plains To Rio Grand Rift: Late Cenozoic Evolution Of Central Colorado, E. M. Leonard, Mary S. Hubbard, S. A. Kelley, E. Evanoff, C. S. Siddoway, C. G. Oviatt, M. Heizler, M. Timmons

Geosciences Faculty Publications

No abstract provided.

Dextral Shear Along The Eastern Margin Of The Colorado Plateau- A Kinematic Link Between Laramide Contraction And Rio Grande Rifting (Ca 75 Ma To 13 Ma), T. F. Wawrzyniec, J. W. Geissman, M. D. Melker, Mary S. Hubbard

Geosciences Faculty Publications

Kinematic data associated with both Laramide‐age and ‐style and Rio Grande rift‐related structures show that the latest Cretaceous to Neogene interaction between the Colorado Plateau and the North American craton was dominantly coupled with a component of dextral shear. Consistent with earlier studies, minor‐fault data in this study yielded results of varied kinematics. Inverted to a common northeast‐oriented hemisphere, the mean trend of kinematic shortening associated with Laramide‐age structures is 056∘±6" role="presentation" style="box-sizing: border-box; display: inline; line-height: normal; word-spacing: normal; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px …

Field Relations, Structural Geology, And Geochemistry Of The Jonestown Volcanic Field, Lebanon County, Southeastern Pennsylvania, Tristan J. Ashcroft

Geology Theses and Dissertations

The Jonestown Volcanic Field is a five kilometer by fifteen kilometer area of volcanic and hypabyssal rocks, basalt and diabase, located in southeastern Pennsylvania. These igneous rocks presently occur within an allochthonous belt of Ordovician deep water sedimentary rocks and Taconic flysch rocks known collectively as the Hamburg Klippe. Detailed field mapping during this project has revealed that the contacts between the igneous rocks and the flysch are not conformable. The volcanic rocks are associated with the Ordovician limestone that is adjacent to these volcanics. This limestone also is not conformable to the Hamburg Klippe sediments, rather it shares outcrop …

The Use Of A Synthetic Binary Solid Solution To Model Igneous Textural Evolution, Elizabeth Scott

Geology Theses and Dissertations

Crystallization experiments using a synthetic igneous analog have shown that grain boundary migration can take place in melt-present environments (Means and Park, 1994). In order to evaluate the importance of metamorphic processes during the textural evolution of a crystal mush, microstructural evidence is needed to link them with final igneous textures. In natural magmatic systems, plagioclase may provide a microstructural link; plagioclase solid solution enables the process of chemical zoning and preserves a record of crystal morphology (and chemistry) during growth. If metamorphic processes are common, they should affect the zoning patterns of plagioclase crystals.
A petrographic stage heater apparatus …

Development Of A Circa 2000 Landcover Database For The United States, Collin Homer, Chengquan Huang, Limin Yang, Bruce K. Wylie

United States Geological Survey: Publications

Multi-Resolution Land Characterization 2000 (MRLC 2000) is a second-generation federal consortium to create an updated pool of nation-wide Landsat 7 imagery, and derive a second-generation National Land Cover Database (NLCD 2000). This multi-layer, multisource database will include a suite of 30-meter resolution data that will serve as standardized ingredients for the production of land cover – both nationally and locally. This database will also provide the framework to allow flexibility in developing and applying suites of independent data layers. These nationally standardized independent data layers or components, will be useful not only within the land-cover classification but as data themes …

Derivation Of A Tasseled Cap Transformation Based On Landsat 7 At-Satellite Reflectance, C. Huang, Bruce K. Wylie, Limin Yang, Collin Homer, Gregory Zylstra

United States Geological Survey: Publications

A new tasseled cap transformation based on Landsat 7 at-satellite reflectance was developed. This transformation is most appropriate for regional applications where atmospheric correction is not feasible. The brightness, greenness and wetness of the derived transformation collectively explained over 97% of the spectral variance of the individual scenes used in this study.

Assessment Of Elemental Concentrations In Streams Of The New Lead Belt In Southeastern Missouri, 2002–05, William G. Brumbaugh, Thomas W. May, John M. Besser, Ann L. Allert, Christopher J. Schmitt

United States Geological Survey: Publications

Concerns about possible effects of lead-mining activities on the water quality of federally protected streams located in southeastern Missouri prompted a suite of multidisciplinary studies to be conducted by the U.S. Geological Survey. As part of this investigation, a series of biological studies were initiated in 2001 for streams in the current mining region and the prospecting area. In this report, results are examined for trace elements and other selected chemical measurements in sediment, surface water, and sediment interstitial (pore) water sampled between 2002 and 2005 in association with these biological studies. Compared to reference sites, fine sediments collected downstream …

Organochlorine Chemical Residues In Fish From The Mississippi River Basin, 1995, C.J. Schmitt

United States Geological Survey: Staff Publications

µ≤≥

Fish were collected in late 1995 from 34 National Contaminant Biomonitoring Program (NCBP) stations and 13 National Water Quality Assessment Program (NAWQA) stations in the Mississippi River basin (MRB) and in late 1996 from a reference site in West Virginia. Four composite samples, each comprising (nominally) 10 adult common carp (Cyprinus carpio) or black bass (Micropterus spp.) of the same sex, were collected from each site and analyzed for organochlorine chemical residues by gas chromatography with electron capture detection. At the NCBP stations, which are located on relatively large rivers, concentrations of organochlorine chemical residues were generally lower than …

Evidence For The Timing And Duration Of The Last Interglacial Period From High-Precision Uranium-Series Ages Of Corals On Tectonically Stable Coastlines, Daniel R. Muhs

United States Geological Survey: Staff Publications

The last interglacial period has a timing and duration that can be estimated from U-series dating of emergent, coral-bearing deposits on tectonically stable coastlines. High-precision dating from Bermuda, the Bahamas, Hawaii, and Australia suggests that the last interglacial period had a sea level at least as high as present from ∼128,000 to 116,000 yr B.P. Sea level reached a near-present level more quickly after the close of the penultimate glacial period than at the close of the last glacial period and the duration of high sea level is longer than that implied by the deep-sea record.

Water Well And Spring Map Of The Somerset 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson

Map and Chart--KGS

No abstract provided.

Water Well And Spring Map Of The Evansville 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson

Map and Chart--KGS

No abstract provided.

Water Well And Spring Map Of The Beaver Dam 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson

Map and Chart--KGS

No abstract provided.

Water Well And Spring Map Of The Lexington 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson

Map and Chart--KGS

No abstract provided.

Groundwater Quality In Kentucky: Arsenic, R. Stephen Fisher

Information Circular--KGS

Arsenic is a naturally occurring element found in low concentrations in rocks, soils, water, plants, and animals (Nriagu, 1994 a, b). In Kentucky, arsenic is commonly found in iron sulfide minerals associated with coal deposits and black shales. Arsenic is released when iron sulfides oxidize during weathering. Once released, it is readily sorbed onto iron oxides and iron oxyhydroxides, which limits arsenic concentrations in the near-surface environment.

Water Well And Spring Map Of The Louisville 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson

Map and Chart--KGS

No abstract provided.

Water Well And Spring Map Of The Campbellsville 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson

Map and Chart--KGS

No abstract provided.

Water Well And Spring Map Of The Harrodsburg 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson

Map and Chart--KGS

No abstract provided.

Inventory Of Karst Springs Of Fayette County, Kentucky, James C. Currens, Qianhong Wu, Kenneth G. Pidgeon

Map and Chart--KGS

The purpose of this publication is to document karst springs in Fayette County and provide a resource to help the county's citizens avoid the geologic hazards associated with building near springs during future urban development. It may be used as an aid in locating potential groundwater discharge points in case of hazardous material spills, and to provide a foundation for future studies of the hydrogeology and karst geology of the Inner Bluegrass Region.

It is also a basic historical record of the springs of Fayette County. Although over 350 springs are reported here, this inventory is not exhaustive. At the …

Carboniferous Stratigraphy In The Vicinity Of The Daniel Boone National Forest, Donald R. Chesnut Jr.

Map and Chart--KGS

Middle Carboniferous strata on the western margin of the Eastern Kentucky Coal Field crop out along a north-northeast-trending belt sometimes referred to as the western belt of outcrop of the central Appalachian Basin. This belt also coincides with the Daniel Boone National Forest. These rocks are important because they contain coal, oil, and groundwater, and helped create the ruggedly beautiful canyons, rapids, falls, and arches in the national forest and nearby state parks. This report describes the general stratigraphy of these Carboniferous rocks, and is designed to assist stratigraphers, coal geologists, forest managers, science educators, and geology students.

Two cross …

Mapped Karst Groundwater Basins In The Lexington 30 X 60 Minute Quadrangle, James C. Currens, Randall L. Paylor, Joseph A. Ray

Map and Chart--KGS

This map shows karst groundwater basins in the Lexington quadrangle, determined primarily by groundwater tracer studies. It can be used to quickly identify the groundwater basins and springs to which a site may drain. Major springs and the relative size of their catchment areas can be evaluated for potential as water supplies. The map also serves as a geographic index to literature on karst groundwater in the area.

Kentucky Is Karst Country! What You Should Know About Sinkholes And Springs, James C. Currens

Information Circular--KGS

Kentucky is one of the most famous karst areas in the world. What is karst? It's a landscape with sinkholes, sinking streams, caves, and springs. Much of Kentucky's beautiful scenery, particularly in the Inner Bluegrass Region, is the result of the development of karst landscape. A large amount of Kentucky's prime farmland (including its famous horse farms) is underlain by karst, and springs and wells in karst areas supply water to thousands of homes. Many of Kentucky's major cities, including Frankfort, Louisville, Lexington, Lawrenceburg, Georgetown, Winchester, Paris, Versailles, Nicholasville, Fort Knox, Bowling Green, Elizabethtown, Munfordville, Russellville, Hopkinsville, …

Generalized Geologic Map For Land-Use Planning: Lexington And Fayette County, Kentucky, Daniel I. Carey, Martin C. Noger, Paul Howell

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes.

Water Well And Spring Map Of The Falmouth, Cincinnati, And Madison 30 X 60 Minute Quadrangles, Kentucky, Bart Davidson

Map and Chart--KGS

No abstract provided.

Bronston And Burnside Members: Subdivision Of The St. Louis Limestone In South-Central Kentucky, Garland R. Dever Jr., Jack R. Moody

Report of Investigations--KGS

The St. Louis Limestone (Mississippian) of south-central Kentucky consists of two major lithologic units that herein are named, in ascending order, the Bronston Member and Burnside Member. Two other lithologic units occurring in the St. Louis Limestone and in correlative rocks of the Slade Formation (Mississippian), which extends from south-central into northeastern Kentucky, herein are named the Ringgold Bed and Big Sinking Bed.

The principal part of the St. Louis Member of the Slade Formation, which consists of Burnside lithologies, herein is renamed the Burnside Member of the Slade. This renaming addresses the problem associated with the previous use of …

Field Trip Guide (For The Nebraska Well Drillers Association) Central Nebraska Geology, James W. Goeke, Robert F. Diffendal Jr., Duane A. Eversoll

Conservation and Survey Division: Faculty and Staff Publications

Field trip guide for the Nebraska Well Drillers Association covering central Nebraska geology from 2002.

Banner County Test Hole Logs, Frank A. Smith

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Creep Critters From Nebraska's Past, Roger K. Pabian

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Impact Spherules From Western Australia: A Textural Analysis Of Really Old Tiny Rocks, Dawn C.S. Ruth

Honors Papers

The fourth shale macroband of the Dales Gorge Member of the Brockman Iron Formation in the Hamersley Basin in Western Australia contains a 2.49 billion years-old impact ejecta layer (Hassler and Simonson,2001). The S4 layer is the least studied Paleoproterozoic impact layer in the Hamersley Basin. It displays textures and replacement minerals not seen in other layers. Analysis of this layer will help our understanding of the processes that form impact ejecta, especially in the Paleoproterozoic.

It is believed that these ejecta settled in a deep basin environment; laterally extensive beds and mud-sized grains are evidence of the deep basin …

Stratigraphy And Diagenesis Of The Paleoproterozoic Bushy Park Zinc-Lead Deposit, South Africa, William Daniel Baugaard

Masters Theses

“The Bushy Park zinc-lead deposit is located in the Northern Cape Province, South Africa. The sulfides are hosted by karst-related breccias that were formed in carbonate shelf deposits of the Neoarchean (2.55 Ga) Campbellrand Subgroup. These rocks are dolomitized completely and silicified partially but have not undergone major metamorphism and thus display remarkable preservation of depositional fabrics. The stratigraphic interval includes the Papkuil and Klippan Formations (> 210 m), a sequence of cyclic microbial laminates interbedded with domed and columnar stromatolites. The Klippan is distinguished from other formations b intense silicification and brecciation. These strata are overlain by the Kogelbeen …