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Timing Of Late Holocene Earthquakes On The Eastern Düzce Fault And Implications For Slip Transfer Between The Southern And Northern Strands Of The North Anatolian Fault System, Bolu, Turkey, Christopher Hitchcock, Erhan Altunel, A. Aykut Barka, Jeffrey Bachhuber, William Lettis, John Helms, Scott Lindvall Jan 2003

Timing Of Late Holocene Earthquakes On The Eastern Düzce Fault And Implications For Slip Transfer Between The Southern And Northern Strands Of The North Anatolian Fault System, Bolu, Turkey, Christopher Hitchcock, Erhan Altunel, A. Aykut Barka, Jeffrey Bachhuber, William Lettis, John Helms, Scott Lindvall

Turkish Journal of Earth Sciences

Results of trenching across the eastern Düzce Fault document that surface rupture has occurred repeatedly on the fault prior to the 1999 Düzce earthquake, and that offset during previous earthquakes occurred at the same location and with similar amounts and type of slip as that of the 1999 earthquake. The most recent pre-1999 earthquake on the fault occurred about 300 years ago. At least four and possibly five earthquakes (including 1999) have occurred in the past 2100 years. The earthquake recurrence interval ranges from 300 to 800 years. Estimates of cumulative slip on the northern and southern branches of the …

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Earthquake Faulting At Ancient Cnidus, Sw Turkey, Erhan Altunel, Iain S. Stenwart, Luigi Piccardi, A. Aykut Barka Jan 2003

Earthquake Faulting At Ancient Cnidus, Sw Turkey, Erhan Altunel, Iain S. Stenwart, Luigi Piccardi, A. Aykut Barka

Turkish Journal of Earth Sciences

The ruins of Cnidus, an important ancient city in southwestern Asia Minor, lie directly on an earthquake fault - the Cnidus Fault. Offset and deformed archaeological remains along the trace of the fault testify to its recent activation. The ancient city's famous Round Temple of Aphrodite is vertically offset by 0.35 m across the fault. The fault also forms the back wall to the Sanctuary of Demeter where Roman-age walls are displaced and deformed by slip on the fault. Archaeological evidence suggests multiple episodes of abrupt destruction at the site and, in the Sanctuary of Demeter, indicates past earthquake surface …

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Earthquakes And Seismic Faulting: Effects On Tunnels, Villy A. Kontogianni, Stathis C. Stiros Jan 2003

Earthquakes And Seismic Faulting: Effects On Tunnels, Villy A. Kontogianni, Stathis C. Stiros

Turkish Journal of Earth Sciences

A study of tunnels in areas affected by strong earthquakes in the last 50-100 years revealed at least three cases of tunnels damaged by earthquake shaking or offset by seismic faulting, including the Bolu (Turkey) twin tunnels, which collapsed during the 1999 Düzce earthquake. These data indicate that tunnels cannot be considered as structures invulnerable to earthquakes. Furthermore, the tectonic offset of tunnels shows that certain observed seismic surface ruptures are not necessarily indicative of tectonic faulting and represent only secondary local ground instability effects.

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Metabasite Blocks From The Koçyaka Hp-Lt Metamorphic Rocks, Konya, Central Anatolia: Geochemical Evidence For An Arc-Back-Arc Pair?, Peter A. Floyd, L. Özgül, M. Cemal Göncüoğlu Jan 2003

Metabasite Blocks From The Koçyaka Hp-Lt Metamorphic Rocks, Konya, Central Anatolia: Geochemical Evidence For An Arc-Back-Arc Pair?, Peter A. Floyd, L. Özgül, M. Cemal Göncüoğlu

Turkish Journal of Earth Sciences

The Kütahya-Bolkardağ Belt, situated on the northern margin of the Tauride-Anatolide Platform, includes slices of HP/LT metamorphic rocks adjacent to allochthonous ophiolitic fragments. The Koçyaka Metamorphic Complex is one such thrust slice and is located to the northeast of Konya. The local tectonostratigraphic succession consists of Upper Cretaceous calcareous metasediments overlain respectively by the Altınekin and Akçasar mélanges of ophiolitic character. Both mélanges contain metabasites (pillow lavas and amphibolites) overprinted with HP-LT glaucophanitic assemblages and later low-grade facies associations. The geodynamic significance of the ophiolites prior to dismemberment (as oceanic crust) is in dispute, being either interpreted as a separate …

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Geology And Hydrothermal Alteration Of The Aydın-Salavatlı Geothermal Field, Western Anatolia, Turkey, İsmai̇l Hakki Karamanderesi̇, Cahi̇t Helvaci Jan 2003

Geology And Hydrothermal Alteration Of The Aydın-Salavatlı Geothermal Field, Western Anatolia, Turkey, İsmai̇l Hakki Karamanderesi̇, Cahi̇t Helvaci

Turkish Journal of Earth Sciences

The Aydın-Salavatlı geothermal field is located in the middle part of the Büyük Menderes Graben, and is characterized by normal-fault structures. The stratigraphic sequence of the Aydın-Salavatlı geothermal field consists of metamorphic rocks of the Menderes Massif and sedimentary rocks deposited during the rifting period of the Menderes Massif in the Miocene. Geological data suggest that there is a connection between tectonic development and periods of hydrothermal alteration. Hydrothermal alteration in the Aydın-Salavatlı geothermal field occurred in five distinct periods, and all are related to different stages of faulting systems, from the Middle Miocene up to the present. The first …

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Roveacrinids From Northern Arabian Plate In Se Turkey, Anna Farinacci, Riccardo Manni Jan 2003

Roveacrinids From Northern Arabian Plate In Se Turkey, Anna Farinacci, Riccardo Manni

Turkish Journal of Earth Sciences

Crinoid remains from Cenomanian limestones in SE Anatolia have been studied. These crinoids belong to the family Roveacrinidae and are characterised by their lacking a stem and free living above the sea floor. A new species, Roveacrinus derdereensis Manni, n. sp., has been erected.

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Mineralogy And Geochemistry Of Melilite Leucitites, Balçıkhisar, Afyon (Turkey), Cüneyt Akal Jan 2003

Mineralogy And Geochemistry Of Melilite Leucitites, Balçıkhisar, Afyon (Turkey), Cüneyt Akal

Turkish Journal of Earth Sciences

The Middle Miocene Afyon volcanic complex crops out in west-central Anatolia and comprises products of extensive potassic-ultrapotassic volcanic activity that intrude and/or cover the sedimentary formations of the western Taurides. Based on their stratigraphic setting, three stages of potassic and ultrapotassic volcanism are distinguishable. Melilite-leucitite lavas are the products of the first stage and followed by lamproites that represent the second stage of volcanism. The leucitite block- and fragment-rich Balçıkhisar volcaniclastic succession overlies the products of the first and second stage volcanism. Lacustrine sedimentary rocks cover the products of first and second stage volcanism. Lacustrine sedimentary rocks are gradationally overlain …

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Traces Of Ancient Earthquakes In Medieval Cities Along The Silk Road, Northern Tien Shan And Dzhungaria, Andrey Korjenkov, Karl Baipakov, Claudia Chang, Yury Peshkov, Tamara Savelieva Jan 2003

Traces Of Ancient Earthquakes In Medieval Cities Along The Silk Road, Northern Tien Shan And Dzhungaria, Andrey Korjenkov, Karl Baipakov, Claudia Chang, Yury Peshkov, Tamara Savelieva

Turkish Journal of Earth Sciences

The evidence for earthquake destruction at medieval cities along the Silk Road from 800 A.D. to 1500 A.D. was examined using techniques of archaeoseismological mapping of architectural components at three currently excavated sites in southern Kazakhstan: Koylyk (Antonovka), Talgar (Talkhir) and Akyrtash, located on the northern branch of the Silk Road, Kazakhstan. This study revealed the following features of seismic activity at all three sites: (a) fractures cutting through a few adjacent bricks; (b) wall-tilts and collapses; (c) horizontal shift of bricks and stones; (d) rotation of stones and bricks. These types of destruction occurred at or very near the …

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Stream Bank Stability In Eastern Nebraska, Philip J. Soenksen, Mary J. Turner, Benjamin J. Dietsch, Andrew Simon Jan 2003

Stream Bank Stability In Eastern Nebraska, Philip J. Soenksen, Mary J. Turner, Benjamin J. Dietsch, Andrew Simon

United States Geological Survey: Publications

Dredged and straightened channels in eastern Nebraska have experienced degradation leading to channel widening by bank failure. Degradation has progressed headward and affected the drainage systems upstream from the modified reaches. This report describes a study that was undertaken to analyze bank stability at selected sites in eastern Nebraska and develop a simplified method for estimating the stability of banks at future study sites. Bank cross sections along straight reaches of channel and geotechnical data were collected at approximately 150 sites in 26 counties of eastern Nebraska. The sites were categorized into three groups based on mapped soil permeability. With …

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Streambed Adjustment And Channel Widening In Eastern Nebraska, David L. Rus, Benjamin J. Dietsch, Andrew Simon Jan 2003

Streambed Adjustment And Channel Widening In Eastern Nebraska, David L. Rus, Benjamin J. Dietsch, Andrew Simon

United States Geological Survey: Publications

In eastern Nebraska, stream straightening and dredging efforts since the 1890s have disturbed the natural equilibrium of stream channels and have led to streambed adjustment by degradation and subsequent channel widening. This report describes a study to evaluate the effect these disturbances have had on stream channels in eastern Nebraska.

Two sets of survey data were collected approximately 2 years apart during 1996–99 at 151 primary sites. Additionally, historical streambed-elevation data (dating back to the 1890s) were compiled from several sources for the primary sites and 45 supplemental sites, and relevant disturbances were identified for each of eight basin groupings. …

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Reconnaissance Of Acid Drainage Sources And Preliminary Evaluation Of Remedial Alternatives At The Copper Bluff Mine, Hoopa Valley Reservation, California, Charles N. Alpers, Michael P. Hunerlach, Scott N. Hamlin, Robert A. Zierenberg Jan 2003

Reconnaissance Of Acid Drainage Sources And Preliminary Evaluation Of Remedial Alternatives At The Copper Bluff Mine, Hoopa Valley Reservation, California, Charles N. Alpers, Michael P. Hunerlach, Scott N. Hamlin, Robert A. Zierenberg

United States Geological Survey: Publications

Acidic drainage from the inactive Copper Bluff mine cascades down a steep embankment into the Trinity River, on the Hoopa Valley Reservation in northern California. The Copper Bluff mine produced about 100,000 tons of sulfide-bearing copper-zinc-gold-silver ore during 1957–1962. This report summarizes the results of a water-resources investigation begun by the U.S. Geological Survey in 1994 with the overall objective of gathering sufficient geochemical, hydrologic, and geologic information so that a sound remediation strategy for the Copper Bluff mine could be selected and implemented by the Hoopa Valley Tribe. This study had the following specific objectives: (1) monitor the quality …

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Sediment-Water Interactions Affecting Dissolved-Mercury Distributions In Camp Far West Reservoir, California, James S. Kuwabara, Charles N. Alpers, Mark Marvin-Dipasquale, Brent R. Topping, James L. Carter, A. Robin Stewart, Steven V. Fend, Francis Parchaso, Gerald E. Moon, David P. Krabbenhoft Jan 2003

Sediment-Water Interactions Affecting Dissolved-Mercury Distributions In Camp Far West Reservoir, California, James S. Kuwabara, Charles N. Alpers, Mark Marvin-Dipasquale, Brent R. Topping, James L. Carter, A. Robin Stewart, Steven V. Fend, Francis Parchaso, Gerald E. Moon, David P. Krabbenhoft

United States Geological Survey: Publications

Field and laboratory studies were conducted in April and November 2002 to provide the first direct measurements of the benthic flux of dissolved (0.2-micrometer filtered) mercury species (total and methylated forms) between the bottom sediment and water column at three sampling locations within Camp Far West Reservoir, California: one near the Bear River inlet to the reservoir, a second at a mid-reservoir site of comparable depth to the inlet site, and the third at the deepest position in the reservoir near the dam (herein referred to as the inlet, midreservoir and near-dam sites, respectively; Background, Fig. 1). Because of interest …

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Late-Holocene Climate And Ecosystem History From Chesapeake Bay Sediment Cores, Usa, Debra A. Willard, Thomas M. Cronin, Stacey Verardo Jan 2003

Late-Holocene Climate And Ecosystem History From Chesapeake Bay Sediment Cores, Usa, Debra A. Willard, Thomas M. Cronin, Stacey Verardo

United States Geological Survey: Staff Publications

Palaeoclimate records from late-Holocene sediments in Chesapeake Bay, the largest estuary in the USA, provide evidence that both decadal to centennial climate variability and European colonization had severe impacts on the watershed and estuary. Using pollen and dinoflagellate cysts as proxies for mid-Atlantic regional precipitation, estuarine salinity and dissolved oxygen (DO) during the last 2300 years, we identified four dry intervals, centred on ad 50 (P1/D1), ad 1000 (P2/D2), ad 1400 (P3) and ad 1600 (P4). Two centennial-scale events, P1/D1 and P2/D2, altered forest composition and led to increased salinity and DO levels in the estuary. Intervals P3 and P4 …

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Seasonal Distribution Of Migratory Tree Bats (Lasiurus And Lasionycteris) In North America, Paul M. Cryan Jan 2003

Seasonal Distribution Of Migratory Tree Bats (Lasiurus And Lasionycteris) In North America, Paul M. Cryan

United States Geological Survey: Staff Publications

Despite evidence of migration in North American tree bats (genera Lasiurus and Lasionycteris), details regarding seasonal movements in these widely distributed species are few. This study attempted to clarify patterns of seasonal distribution by mapping museum occurrence records by month. Monthly changes in the distribution of records indicate seasonal movements of tree bats. Northward migration during spring by Lasiurus cinereus appears to stem from wintering grounds in California and Mexico. During summer, male L. cinereus is mainly distributed in western North America, whereas females dominate samples from eastern regions. Lasiurus borealis winters in southeastern areas and expands its range …

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Last Glacial Loess In The Conterminous Usa, E. Arthur Bettis Iii, Daniel R. Muhs, Helen M. Roberts, Ann G. Wintle Jan 2003

Last Glacial Loess In The Conterminous Usa, E. Arthur Bettis Iii, Daniel R. Muhs, Helen M. Roberts, Ann G. Wintle

United States Geological Survey: Staff Publications

The conterminous United States contains an extensive and generally well-studied record of Last Glacial loess. The loess occurs in diverse physiographic provinces, and under a wide range of climatic and ecological conditions. Both glacial and non-glacial loess sources are present, and many properties of the loess vary systematically with distance from loess sources. United States’ mid-continent Last Glacial loess is probably the thickest in the world, and our calculated mass accumulation rates (MARs) are as high as 17,500 g/m2/yr at the Bignell Hill locality in Nebraska, and many near-source localities have MARs greater than 1500 g/m2/yr. …

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Groundwater Flow Andwater Quality – A Flowpath Study In The Seminolewell Field, Cedar Rapids, Iowa, Douglas J. Schnoebelen, Michael J. Turco, John D. North Jan 2003

Groundwater Flow Andwater Quality – A Flowpath Study In The Seminolewell Field, Cedar Rapids, Iowa, Douglas J. Schnoebelen, Michael J. Turco, John D. North

United States Geological Survey: Staff Publications

In Iowa, alluvial aquifers near major rivers are a source of water for many communities. The City of Cedar Rapids withdraws water from wells completed in the Cedar River alluvium, a shallow alluvial aquifer adjacent to the Cedar River. The City of Cedar Rapids is located within Linn County in east-central Iowa, and water for the City is supplied by four well fields (East, Northwest, Seminole, and West well fields) along the Cedar River. The City has a population of about 121,000, and several large industries are major water users. Currently, per capita water usage in the City is nearly …

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Eutrophication And Carbon Sources In Chesapeake Bay Over The Last 2700 Yr: Human Impacts In Context, John F. Bratton, Steven M. Colman, Robert R. Seal, Ii Jan 2003

Eutrophication And Carbon Sources In Chesapeake Bay Over The Last 2700 Yr: Human Impacts In Context, John F. Bratton, Steven M. Colman, Robert R. Seal, Ii

United States Geological Survey: Staff Publications

To compare natural variability and trends in a developed estuary with human-influenced patterns, stable isotope ratios (δ13C and δ15N) were measured in sediments from five piston cores collected in Chesapeake Bay. Mixing of terrestrial and algal carbon sources primarily controls patterns of δ13Corg profiles, so this proxy shows changes in estuary productivity and in delivery of terrestrial carbon to the bay. Analyses of δ15N show periods when oxygen depletion allowed intense denitrification and nutrient recycling to develop in the seasonally stratified water column, in addition to recycling taking place in surficial …

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Generalized Geologic Map For Land-Use Planning: Berea 7.5-Minute Quadrangle, Kentucky, Daniel I. Carey, Martin C. Noger, Paul Howell Jan 2003

Generalized Geologic Map For Land-Use Planning: Berea 7.5-Minute Quadrangle, 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 conditions that affect the selection of sites for various purposes. Site-specific investigations should be made by a professional geologist.

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Water Well And Spring Map Of The Morehead 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson Jan 2003

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

Map and Chart--KGS

No abstract provided.

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Water Well And Spring Map Of The Williamson 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson Jan 2003

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

Map and Chart--KGS

No abstract provided.

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Water Well And Spring Map Of The Elizabethtown 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson Jan 2003

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

Map and Chart--KGS

No abstract provided.

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Generalized Geologic Map For Land-Use Planning: Scott County, Kentucky, Daniel I. Carey, Martin C. Noger Jan 2003

Generalized Geologic Map For Land-Use Planning: Scott County, Kentucky, Daniel I. Carey, Martin C. Noger

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. The properties of thick soils may supersede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.

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Generalized Geologic Map For Land-Use Planning: Edmonson County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey Jan 2003

Generalized Geologic Map For Land-Use Planning: Edmonson County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey

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. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site to site basis. At any site, it is important to understand both the soils and the underlying rock.

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Generalized Geologic Map For Land-Use Planning: Jessamine County, Kentucky, Daniel I. Carey, Martin C. Noger, Paul Howell Jan 2003

Generalized Geologic Map For Land-Use Planning: Jessamine 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. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site to site basis. At any site, it is important to understand both the soils, and the underlying rock.

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Generalized Geologic Map For Land-Use Planning: Woodford County, Kentucky, Daniel I. Carey, Martin C. Noger, Paul Howell Jan 2003

Generalized Geologic Map For Land-Use Planning: Woodford 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. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site to site basis. At any site, it is important to understand both the soils, and the underlying rock.

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Water Well And Spring Map Of The Pikeville 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson Jan 2003

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

Map and Chart--KGS

No abstract provided.

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Water Well And Spring Map Of The Tompkinsville 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson Jan 2003

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

Map and Chart--KGS

No abstract provided.

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Water Well And Spring Map Of The Murray 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson Jan 2003

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

Map and Chart--KGS

No abstract provided.

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Water Well And Spring Map Of The Hopkinsville 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson Jan 2003

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

Map and Chart--KGS

No abstract provided.

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Water Well And Spring Map Of The Madisonville 30 X 60 Minute Quadrangle, Kentucky, Bart Davidson Jan 2003

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

Map and Chart--KGS

No abstract provided.

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