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Articles 54391 - 54420 of 59385
Full-Text Articles in Entire DC Network
Paleoenvironmental Data For N. W. Georgia, U.S.A., From Fossils In Cave Speleothems, George A. Brook, Eugene P. Keferl, Rudy J. Nickmann
Paleoenvironmental Data For N. W. Georgia, U.S.A., From Fossils In Cave Speleothems, George A. Brook, Eugene P. Keferl, Rudy J. Nickmann
International Journal of Speleology
Pollen grains and gastropod shells in two speleothems from Red Spider Cave, Georgia indicate that ca. 10,000 yr B.P. the vegetation near the cave was Mixed Mesophytic Forest. Conditions were cooler and moister than today and a shallow pond existed in the doline above the cave. As these findings support palynologic evidence from nearby pond sites it is clear that cave speleothems are a potential source of paleoecological data to ca. 350,000 yr. B.P.
Diatom, Contributors Of Coralloid Speleothems, From Togawa-Sakaidani-Do Cave In Miyazaki Prefecture, Central Kyushu, Japan, Naruhiko Kashima, Teruo Irie, Nobuhiro Kinoshita
Diatom, Contributors Of Coralloid Speleothems, From Togawa-Sakaidani-Do Cave In Miyazaki Prefecture, Central Kyushu, Japan, Naruhiko Kashima, Teruo Irie, Nobuhiro Kinoshita
International Journal of Speleology
Coralloid speleothems are commonly distributed in Togawa-Sakaidani-do Cave in Miyazaki Prefecture, Central Kyushu, but their speleological study has not heretofore been achieved. Light and scanning microscopes analyses revealed that coralloid speleothems consist of alternating layers of diatom colonies, detrital minerals and clay. Electron microprobe analysis shows coralloid speleothems to be silicious. This paper asserts that diatom (genus Melosira) is one of the important contributors to siliceous coralloid speleothems in the threshold zone at non-calcareous caves.
Les Mésaventures Des Sources De L'Estavelle Et De L'Inversac En Languedoc Méditerranéen, Bernard Gèze
Les Mésaventures Des Sources De L'Estavelle Et De L'Inversac En Languedoc Méditerranéen, Bernard Gèze
International Journal of Speleology
The Estavelle and the Inversac are two celebrated springs in the Mediterranean Languedoc (South of France). Unfortunately, the first one has been chosen as a type for the karstic cavities alternatively absorbing or discharging the waters, according to the season, which has never been the case. On the opposite, the second one can be taken as model for this alternation as swallow hole or emergence.
Carbonate Surface Solution In The Classical Karst, Franco Cucchi, Fabio Forti, Furio Finocchiaro
Carbonate Surface Solution In The Classical Karst, Franco Cucchi, Fabio Forti, Furio Finocchiaro
International Journal of Speleology
The current research on the dissolution of carbonate rocks in the Karst of Trieste indicates that the average degradation of surfaces exposed to atmospheric agents is 0.028 mm/year with an average rainfall of 1350 mm. The maximum levels (0.031 mm/year) correspond to micro-crystalline limestones, the minimum values (0.014 mm/year) to dolomites.
Stratigraphic Sections In The Ste. Genevieve Formation (Middle Mississippian) Exposed In Garrison Chapel Karst Area Caverns - Western Monroe County, Indiana Usa, Garre A. Conner
International Journal of Speleology
The Ste. Genevieve Formation and related strata in the Blue River Group comprise more than 75 meters of Middle Mississippian carbonate deposition across the Indiana portion of the Eastern Interior Basin in Valmeyeran seaways. Forty kilometres of subterranean caverns occur in this carbonate rock sequence in the Garrison Chapel karst area where blind valleys are a striking topographical feature. The bedrock floor of a karst valley is locally accordant with a continuous horizon of lithographic limestone named Indian Creek Beds and illustrated on five cavern stratigraphic reference profiles.
Relationships Between The Internal And External Evolution Of The Monte Cucco Karst Complex, Umbria, Central Italy, Fausto Guzzetti
Relationships Between The Internal And External Evolution Of The Monte Cucco Karst Complex, Umbria, Central Italy, Fausto Guzzetti
International Journal of Speleology
The relationships between the internal and external evolution of the Mt. Cucco karst complex are studied. A classic set of equations, involving the oxidation of hydrogen sulphide, originated at depth in an evaporitic formation, is used to explain the presence of massive gypsum deposits in the Mt. Cucco and the Faggeto Tondo caves. The distribution and the morphology of more than 30 caves in the system, the presence of gypsum, always located along faults, and the presence of broken stalactites and columns, suggest that the evolution of the karst system has been controlled by tectonic movements. Relationships between the development …
Depositional Environments Of A Portion Of The Bullion Creek Formation (Paleocene), Western Billings County, North Dakota, Rodney K. Perkins
Depositional Environments Of A Portion Of The Bullion Creek Formation (Paleocene), Western Billings County, North Dakota, Rodney K. Perkins
Theses and Dissertations
The Bullion Creek Formation (Paleocene) in North Dakota is part of an Upper Cretaceous to Eocene wedge of siliciclastic rocks formed during uplift associated with the Laramide Orogeny. The Bullion Creek Formation consists predominantly of mudrocks , with fine-grained sandstone, lignite, and rare limestone lenses . Previous workers have postulated combinations of fluvial and lacustrine depositional environments for the rocks.
The study area covers 15 square kilometres in the badlands of the Little Missouri River in western Billings County, North Dakota, where approximately the upper 75 metres of the Bullion Creek Formation ls exposed. Twenty nine stratigraphic sections were measured …
A Seismic Refraction Study Of A Portion Of The Northeastern Margin Of The Tualatin Valley, Oregon, David John Nazy
A Seismic Refraction Study Of A Portion Of The Northeastern Margin Of The Tualatin Valley, Oregon, David John Nazy
Dissertations and Theses
The Tualatin Valley is a well defined elliptical basin centered at Hillsboro, with a major axis trending roughly N65°W. The valley is bordered on the northeast by the Tualatin Mountains (Portland Hills) which are a faulted, northwest-trending asymmetrical anticline. Topographic and geophysical evidence have defined the Portland Hills fault, which occurs along the northeast side of the Tualatin Mountains. The possibility that a fault or fault zone occurs along the southwest side of the Tualatin Mountains was investigated in this study.
Textural And Mineralogical Characteristics Of Altered Grande Ronde Basalt, Northeastern Oregon : A Natural Analog For A Nuclear Waste Repository In Basalt, Paul M. Trone
Dissertations and Theses
Altered flows that are low-MgO chemical types of the Grande Ronde Basalt crop out in the steep walls of the Grande Ronde River canyon near Troy, Wallowa County, Oregon. The alteration effects in these flows are being investigated as a natural analog system to a high level nuclear waste repository in basalt. The flows within the study are referred to as the analog flow, in which the alteration effects are the strongest, and the superjacent flow. The analog flow crops out at Grande Ronde River level and a roadcut-outcrop is developed in the flow-top breccia of this flow. The two …
The Effect Of Particle Size On Phosphate Adsorption By Fluvial Sediment, Michael F.A. Stone
The Effect Of Particle Size On Phosphate Adsorption By Fluvial Sediment, Michael F.A. Stone
Theses and Dissertations (Comprehensive)
The quantitative phosphate adsorption behaviour of ten grain size fractions of an experimental sediment (silica sand) and fluvial sediment from two Southwestern Ontario rivers, were evaluated and compared to determine the effect of particle size on phosphate absorption. In addition, the elemental composition of grain size fractions of fluvial sediment were determined by X-Ray fluorescence spectrometry to study the combined effect of particle size and sediment geochemical composition on phosphate adsorption. Results of the adsorption studies indicate that phosphate adsorption per unit mass increases in non-linear fashion with decreasing grain size. The capacity of grain size fractions of silica sand …
Irrigation Water Use In Southern Ontario, Kenneth Iain Macdonald
Irrigation Water Use In Southern Ontario, Kenneth Iain Macdonald
Theses and Dissertations (Comprehensive)
The appreciation of water as a finite resource has engendered a renewed research interest in producing effective water management policies and practices in order to reduce both current and potential demands on existing reserves. Unfortunately, such research, especially in the humid regions of North America, has concentrated on water use in urban areas and has neglected the use of water in irrigation agriculture; even though irrigation is a major consumptive use of water in many localized areas. In addition, research has been dominated by physical, technological and economic viewpoints at the expense of an understanding of the human element in …
The Hydrogeology Of Nags Head Woods, Dare County, North Carolina, Janet Salyer Emry
The Hydrogeology Of Nags Head Woods, Dare County, North Carolina, Janet Salyer Emry
OES Theses and Dissertations
Nags Head Woods, a coastal maritime forest located on a barrier island in eastern North Carolina, stabilizes a back-barrier dune system bordering a tidal marsh. The purpose of this study is to provide basic information about the groundwater geology in Nags Head Woods and to predict the effects upon water levels due to municipal pumping of Fresh Pond, a large lake near the center of the island.
Clean, fine-to-medium sands dominate the top of the surficial (water table) aquifer, underlain by silty fine-to-coarse sands at -4 m elevation. A silty clay bed of very low permeability is present at -12 …
Depositional And Diagenetic History Of The Middle Ordovician Carbonates Of The Shenandoah Valley, Northern Virginia, Lynn Ellen Weyenberg
Depositional And Diagenetic History Of The Middle Ordovician Carbonates Of The Shenandoah Valley, Northern Virginia, Lynn Ellen Weyenberg
OES Theses and Dissertations
An examination of the Middle Ordovician carbonates in northwest Virginia has revealed a particularly sensitive record of deposition and subsidence. Two-hundred acetate peels from six measured stratigraphic sections in Shenandoah County, Virginia were examined to interpret the depositional and diagenetic history. Two major lithofacies have been recognized within the New Market Limestone and three have been recognized in the Lincolnshire Formation. These five lithofacies represent an overall transgressive sequence. This transgression was not uniform but paused several times to allow carbonate deposition to reach sea-level. These shoaling events suggest a slowly subsiding basin in this region. The carbonate rocks within …
A Groundwater Flow Model Of The Aquifer Intercommunication Area, Hanford Site, Washington, Elizabeth G. Simkover
A Groundwater Flow Model Of The Aquifer Intercommunication Area, Hanford Site, Washington, Elizabeth G. Simkover
Dissertations and Theses
Intercommunication has been identified between the unconfined and uppermost confined aquifer systems underlying a portion of the U.S. Department of Energy's Hanford Site. Erosional thinning and fracturing of the basalt confining layer within the study area allows physical contact between the two aquifers, but the vertical hydraulic gradient (a required driving force) is small. To better conceptualize the distribution and volume of the leakage occurring between the aquifer systems, this study investigates the confined Rattlesnake Ridge Aquifer flow system, which appears to be more sensitive to the vertical leakage than the overlying unconfined aquifer.
The flow system of the Rattlesnake …
Land Use In The Amazon: Soil Erosion, Sedimentation, And The Samuel Dam, Doug H. Graham
Land Use In The Amazon: Soil Erosion, Sedimentation, And The Samuel Dam, Doug H. Graham
Peer Reviewed Articles
Doug Graham received a M.A. in Geography in December of 1986. This paper is a summary of his thesis entitled "The Samuel Dam: Land Use, Soil Erosion, and Sedimentation in Amazonia." Graham conducted field research in Brazil during the Summer of 1985, with funding from the Tinker Foundation and the Amazon Research and Training Program. His immediate plans are to continue his training in Geography at the University of Wisconsin-Madison.
Mechanisms Responsible For Sinkhole Flooding On An Urbanized Karst Terrain: South Sunrise / Media Drive, Bowling Green, Kentucky, Thomas Feeney
Mechanisms Responsible For Sinkhole Flooding On An Urbanized Karst Terrain: South Sunrise / Media Drive, Bowling Green, Kentucky, Thomas Feeney
Masters Theses & Specialist Projects
Sinkhole flooding on the urban karst area of Bowling Green, Kentucky, was studied by investigating past flood events in the South Sunrise/Media Drive Sinkhole. The actual flood levels of four floods were compared to levels calculated by an empirical runoff determination method. Outflow capacity tests and dye tracing revealed the nature of drainage within the karst depression.
The Soil Conservation Service runoff determination method and the three-hour maximum rainfall event were used to estimate the level of flooding. Three of the four flood events studied provided deviations between the actual and calculated flood levels of less than 0.26 feet (0.08 …
Geology Newsletter- 1986, Department Of Geology
Geology Newsletter- 1986, Department Of Geology
Geological and Environmental Sciences News
Vol. 1, No. 11
- Dear Alumni and Friends
- Core Research Library
- Advisory Council
- Geology Development Fund
- Faculty Briefs
- Awards and Scholarships
- Alumni Lines
Soil Conservation Provisions Of The 1985 Farm Bill, Monroe Rasnake, Lloyd W. Murdock, Craig Infanger
Soil Conservation Provisions Of The 1985 Farm Bill, Monroe Rasnake, Lloyd W. Murdock, Craig Infanger
Soil Science News and Views
The 1985 Farm Bill which was signed into law on December 23, 1985, contains 3 provisions relating to land use which will have a large impact on Kentucky farmers. The purpose of these provisions is to reduce cropland acreage on highly erodible lands and on wetlands. A description of them follows.
A Hydrogeologic Investigation Of The Balkema Wetland, Daniel V. Fronczek
A Hydrogeologic Investigation Of The Balkema Wetland, Daniel V. Fronczek
Masters Theses
The Balkema wetland, located In southwestern Kalamazoo County, Michigan, represents complex biological and hydrologic Interaction between surface water and a two-aquifer hydrologic system. Situated on the southeastern flank of the Kalamazoo moraine, the glacial geology of the area plays a key role in the understanding of the hydrogeologic function of the wetland. A two-aquifer system, an upper unconfined, and a lower confined, Interact In the vicin ity of the wetland where the c la y /till aqulclude dividing the two systems 1s absent. Various parameters, both hydrologic and geochemical, were measured In the study area, Including specific conductance values of …
Structural, Remote Sensing And Multivariate Correlation Methods As Aids To Mineral Exploration, Central Ireland, D.W. Coller, M.F. Critchley, J.M. Dolan, Ciaran Mcdonnell, C.J. Murphy, W.E.A. Phillips, D.J. Sanderson
Structural, Remote Sensing And Multivariate Correlation Methods As Aids To Mineral Exploration, Central Ireland, D.W. Coller, M.F. Critchley, J.M. Dolan, Ciaran Mcdonnell, C.J. Murphy, W.E.A. Phillips, D.J. Sanderson
Books/Book chapters
This work discusses structural, remote sensing and multivariate correlation methods as aids to mineral exploration in West Central Ireland. The work was performed as part of the EU-funded CREST project.
Late Pleistocene Sciurids From Kokoweef Cave, H. Thomas Goodwin
Late Pleistocene Sciurids From Kokoweef Cave, H. Thomas Goodwin
Loma Linda University Electronic Theses, Dissertations & Projects
Three local (Tamias panamintinus, Ammospermophilus leucurus and Spermophilus variegatus) and five extralocal (Tamias minimus, Tamias palmeri, Marmota flaviventris, Spermophilus townsendii, and Spermophilus lateralis) sciurid species (Sciuridae) were identified from the late Pleistocene-early Holocene Kokoweef Cave paleofauna. This fauna was the first documentation of T. minimus, T. palmeri and S. townsendii from the Pleistocene of the Mohave Desert. The 30-ft sedimentary sequence apparently recorded the mid-to late-Wisconsian introduction of S. lateralis into the Kokweef fauna but otherwise documented general taxonomic stability. The ecological diversity of the fauna was consistent with--but did not require--the hypothesis of more equable late Pleistocene climates, and …
Fracture Detection In A Volcanic Oil Reservoir Using Discriminant Analysis Of Well Log Data, Joseph William Cross
Fracture Detection In A Volcanic Oil Reservoir Using Discriminant Analysis Of Well Log Data, Joseph William Cross
OES Theses and Dissertations
A new method of detecting fractures using well logs is presented. The technique uses discriminant analysis to distinguish fractured from unfractured reservoir rock and was developed for the volcanic pay zone of Jatibarang oilfield, West Java, Indonesia.
The a priori information required to derive the discriminant function was provided by 22 wells known to penetrate intervals of either fractured or unfractured volcanics. The samples consisted of these 22 intervals digitized in one-meter increments (1256 meters total thickness). The discriminating variables were the petrophysical measurements made by 10 different types of well logs.
Discriminant analysis correctly classified 94.2% of the total …
Geology Of The Willamette Pass Area, Cascade Range, Oregon, Neil M. Woller
Geology Of The Willamette Pass Area, Cascade Range, Oregon, Neil M. Woller
Dissertations and Theses
The Willamette Pass area is situated at the intersection of two hypothesized structural features, the Western Cascade-High Cascade boundary and the Eugene-Denio lineament. It is of interest due to its designation by the U.S. Department of the Interior as a Known Geothermal Resource Area.
Volcanic rocks of Oligocene to Pleistocene age are exposed in the study area. The oldest rocks are the Oligocene-Miocene lavas, undifferentiated, which are a diverse unit of ignimbrites and intermediate to silicic flows. The Oligocene-Miocene rhyodacites are a stratigraphically equivalent unit which is predominantly composed of aphyric rhyodacite flows. Middle Miocene volcanism produced the basaltic lavas …
Karstification Of The Pennyroyal Plain Behind The Retreating Chester Escarpment: Warren, Simpson & Logan Counties, Kentucky, Anthony Able
Karstification Of The Pennyroyal Plain Behind The Retreating Chester Escarpment: Warren, Simpson & Logan Counties, Kentucky, Anthony Able
Masters Theses & Specialist Projects
Hydrogeologic investigations were conducted on the drainage systems of an area of the Pennyroyal sinkhole plain of south central Kentucky. The degree of karstification of five area streams was studied to develop an understanding of the evolution of drainage as the landscape changes from a sandstone caprock plateau to a limestone sinkhole plain. The Chester Upland, capped by the Big Clifty Sandstone, possesses predominantly surface drainage and the Pennyroyal Plain, formed on Mississippian limestones, possesses considerable subsurface drainage. As the Chester Upland Escarpment retreats and surface streams are onto the limestones, the streams evolve to become subsurface streams. The five …
Slack-Water Deposits And The Magnitude And Frequency Of Flash Floods, Eastern Kentucky, Russell G. Shepherd, Lisa K. Bienkowski
Slack-Water Deposits And The Magnitude And Frequency Of Flash Floods, Eastern Kentucky, Russell G. Shepherd, Lisa K. Bienkowski
KWRRI Research Reports
The potential for predicting flood magnitude and frequency using sediments deposited in backwater areas during flash floods was investigated on the Cumberland Plateau of eastern Kentucky, a region n9torious for flash flooding. Slack-water deposits are abundant in the area at tributary mouths and bedrock channel expansions. They are identifiable on geologic quandrangle maps, and are locally good potential indicators of maximum flood-crest elevations. However, in this humid region, flash floods could not be distinguished from non-flash floods using slack-water sedimentology.
The results from the slack-water deposits studied indicate that they offer limited potential for predicting flash floods because 1) intense …
Pinuxylon Woolardii Sp. Nov., A New Petrified Taxon Of Pinaceae From The Miocene Basalts Of Eastern Oregon, William D. Tidwell, Lee R. Parker, Vaughn K. Folkman
Pinuxylon Woolardii Sp. Nov., A New Petrified Taxon Of Pinaceae From The Miocene Basalts Of Eastern Oregon, William D. Tidwell, Lee R. Parker, Vaughn K. Folkman
Faculty Publications
Specimens of the new species Pinuxylon wollardii have been collected from Miocene strata near Kurkee, OR. These petrified specimens are unique in that, due to weathering, individual tracheids and ray cells can be separated for detailed SEM studies. This species is characterized by its high number of ray cells; numerous rays; large resin ducts which are commonly paired; primarily uniseriate pitting, two to five (usually three) small, oval or cirular pinoid pits per crossfield; and smooth walls on its transverse (ray) tracheids. The latter character relates this species to taxa in the subgenus Haploxylon of Pinus. Pinuxylon woolardii is most …
Chemical, Physical And Mineralogical Properties Of Mitchell And Tripp Soils In The Nebraska Panhandle, G. A. Uzochukwu, D. T. Lewis
Chemical, Physical And Mineralogical Properties Of Mitchell And Tripp Soils In The Nebraska Panhandle, G. A. Uzochukwu, D. T. Lewis
Nebraska Agricultural Experiment Station: Historical Research Bulletins
Mitchell and Tripp soils are some of the most important agricultural soils in the Nebraska Panhandle. Yet, they have received little attention in terms of their basic chemical, physical, and mineral properties. Management decisions can be made on a more informed basis if this kind of information is available. This study was to acquire the information, with special emphasis on mineralogical properties of the soils and their parent materials. This emphasis was given because it is known that other soils in the region contain volcanic ash in measurable amounts. The presence of volcanic ash in soils has been associated with …
The National Park System And Development On Private Lands: Opportunities And Tools To Protect Park Resources, Michael Mantell
The National Park System And Development On Private Lands: Opportunities And Tools To Protect Park Resources, Michael Mantell
External Development Affecting the National Parks: Preserving "The Best Idea We Ever Had" (September 14-16)
34 pages.
Contains footnotes.
Jurisdictional And Institutional Issues: Public Lands, Robert B. Keiter
Jurisdictional And Institutional Issues: Public Lands, Robert B. Keiter
External Development Affecting the National Parks: Preserving "The Best Idea We Ever Had" (September 14-16)
13 pages.
Contains references.
International Law And External Threats To National Parks, Daniel Barstow Magraw
International Law And External Threats To National Parks, Daniel Barstow Magraw
External Development Affecting the National Parks: Preserving "The Best Idea We Ever Had" (September 14-16)
41 pages.
Contains references.