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Generalized Geologic Map For Land-Use Planning: Whitley County, Kentucky, Daniel I. Carey, Bethany L. Overfield, Randall L. Paylor Jan 2006

Generalized Geologic Map For Land-Use Planning: Whitley County, Kentucky, Daniel I. Carey, Bethany L. Overfield, Randall L. Paylor

Map and Chart--KGS

No abstract provided.


Generalized Geologic Map For Land-Use Planning: Larue County, Kentucky, Bart Davidson, Daniel I. Carey, Adam Pike Jan 2006

Generalized Geologic Map For Land-Use Planning: Larue County, Kentucky, Bart Davidson, Daniel I. Carey, Adam Pike

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 the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Jackson County, Kentucky, Edward C. Hodges, Bart Davidson, Daniel I. Carey Jan 2006

Generalized Geologic Map For Land-Use Planning: Jackson County, Kentucky, Edward C. Hodges, Bart Davidson, 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 the characteristics of both the soils and the underlying rock.


Assessing Water-Supply Potential Of Abandoned Underground Coal Mines In Eastern Kentucky, James S. Dinger, Dennis H. Cumbie, Bart Davidson Jan 2006

Assessing Water-Supply Potential Of Abandoned Underground Coal Mines In Eastern Kentucky, James S. Dinger, Dennis H. Cumbie, Bart Davidson

Report of Investigations--KGS

Use of water in abandoned underground coal mines for municipal, industrial, agricultural, or domestic water supplies is dependent upon the water quantity and quality. For either of these factors, the requirements of the user will play a role in what water quantity or quality is acceptable. This report provides analysis of field-derived water-quality and -quantity characteristics for six abandoned underground coal mines in the Eastern Kentucky Coal Field. In addition, some ancillary data from State regulatory agencies were used to help characterize water quality coming from the mines.

This study demonstrates that water quality in abandoned deep mines can be …


Source Scaling, Subevent Distributions, And Ground-Motion Simulation In The Composite Source Model, Baoping Shi, Zhenming Wang, Edward W. Woolery Jan 2006

Source Scaling, Subevent Distributions, And Ground-Motion Simulation In The Composite Source Model, Baoping Shi, Zhenming Wang, Edward W. Woolery

Report of Investigations--KGS

Predicting strong ground motion from a large earthquake depends to a large extent on the development of a realistic source model. Strong ground motion was simulated using the composite source model. F0or comparison purposes, two different approaches were implemented in the source procedure simulation. For the first approach, the source was taken as a superposition of circular subevents with a constant stress drop. The number of subevents and their radii followed fractal law distribution, specified as a spatial random field, and subevents were allowed to overlap. This resulted in the total area of the subevents being much greater than the …


Using Electron Backscatter Diffraction Patterns To Examine Recrystallization In Polar Ice Sheets, Rachel Obbard, Ian Baker, Katherine Sieg Jan 2006

Using Electron Backscatter Diffraction Patterns To Examine Recrystallization In Polar Ice Sheets, Rachel Obbard, Ian Baker, Katherine Sieg

Dartmouth Scholarship

The fabric of polycrystalline ice is typically described using the c-axis orientation alone, but this is insufficient for a full description of grain orientations in this hexagonal material. Electron backscatter diffraction (EBSD) provides full c- and a-axis orientation of individual grains, and is used here to study Greenland Ice Sheet Project 2 (GISP2) ice specimens from depths of 1551, 1642 and 1745 m. Complete orientation data are used to compare nearest-neighbor relationships to overall fabric and to differentiate between recrystallization mechanisms. Changes in orientation between grains and subgrains in GISP2 specimens were correlated with the appearance of grain boundaries on …


Evaluating The Deep-Sea Coral Acanella From Hawaii As A Paleoceanographic Archive, Geraldine Hourigan Lantier Jan 2006

Evaluating The Deep-Sea Coral Acanella From Hawaii As A Paleoceanographic Archive, Geraldine Hourigan Lantier

Geology Theses and Dissertations

Deep-sea corals have emerged as potential proxies of changing paleoceanographic properties. The utility of deep-sea corals for the purpose of interpreting paleoclimatic reconstructions is still in the discovery phase. However, long life spans, a relatively stable habitat, and unique growth geometry provide support to the growing body of research that has identified deep-sea corals as indicators of past climate and ocean properties. Two colonies of Acanella were collected from the permanent thermocline at depths between 414 and 437 m in the Makapuu Coral Bed, Oahu, HI in 1997 by submersible. Here I present results from a pilot study of the …


Mapping Of A Detachment Fault In Kythera Island And Study Of The Related Structural Shear Sense Indicators, Antonios Marsellos Jan 2006

Mapping Of A Detachment Fault In Kythera Island And Study Of The Related Structural Shear Sense Indicators, Antonios Marsellos

Geology Theses and Dissertations

Kythera Island is located on the prominent submarine horst between Crete and the Peloponnese in the southwestern part of the Aegean. The structure of Kythera is characterized by a pile of tectonic slices derived from different paleogeographic zones. The upper unmetamorphosed units comprise pelagic limestones and cherts of Pindos zone emplaced by thrusting in the Eocene on top of Tripolis zone neritic limestones. These units are separated from the lower metamorphosed unit of Phyllite-Quartzite (PQU) exposed in the northern part of Kythera by an extensional detachment fault of Late Miocene age. The lower tectonic unit of PQU was affected by …


Thermochronology And Provenance Of The Yakutat Terrane, Southern Alaska Based On Fission-Track And U/Pb Analysis Of Detrital Zircon, Stephanie Ellen Perry Jan 2006

Thermochronology And Provenance Of The Yakutat Terrane, Southern Alaska Based On Fission-Track And U/Pb Analysis Of Detrital Zircon, Stephanie Ellen Perry

Geology Theses and Dissertations

Northward transport of the Yakutat terrane along the Transition and Queen Charlotte-Fairweather transform faults led to Neogene collision of the Yakutat terrane with the southern continental Alaska margin. Northward translation resulted in a stratigraphy that records the erosion of thermotectonic terranes along its path. The strata of the Yakutat terrane includes the Lower Oligocene to Lower Eocene Kulthieth Formation, the Upper Eocene to Lower Miocene Poul Creek Formation and the Miocene-Pleistocene Yakataga Formation. Detrital zircon fission-track (DZFT) ages from stratigraphically coordinated samples collected in the Northern Robinson Mountains yield provenance information of the units that can shed light on their …


Assessing The Paleoceanographic Potential Of The Coral Montipora Venosa At Fanning Atoll, Central Equatorial Pacific, Alexa Stolorow Jan 2006

Assessing The Paleoceanographic Potential Of The Coral Montipora Venosa At Fanning Atoll, Central Equatorial Pacific, Alexa Stolorow

Geology Theses and Dissertations

As interest in global climate change increases, so does the need for better and more extensive climate proxies. The central equatorial Pacific has been established as the region with the largest ENSO-related sea surface temperature (SST) and precipitation (PPT) anomalies, which are known to impact global interannual climate variability. To date, the coral genus Porites has been most commonly utilized for coral-based paleo-reconstructions of ENSO and lower frequency phenomena. However, due to questions of biological artifacts in coral, to more fully understand coral-based reconstruction, different coral genera need to be analyzed.
In this study, oxygen (δ18O) and carbon (δ13C) isotopic …


The Effects Of Land Use Changes On Soil Carbon In The Russian Steppe, Andrew M. Ratigliano Jan 2006

The Effects Of Land Use Changes On Soil Carbon In The Russian Steppe, Andrew M. Ratigliano

Geology Theses and Dissertations

Increasing atmospheric CO2 levels within the past few centuries have led to many studies about the global carbon cycle. An important aspect in balancing the modern global carbon budget revolves around a missing sink of carbon. It is thought that the carbon accumulation in soil may be a significant component in this loss. As changes in land use under natural conditions have increased over the years, it is not well understood how these changes may affect the soil carbon. A useful technique in determining these changes are with the use of archived samples. Within a Russian steppe preserve that has …


Thermochronological Evidence For Neogene Incision Of The Rio Pativilca Canyon, Northern Peru, Matthew James Montario Jan 2006

Thermochronological Evidence For Neogene Incision Of The Rio Pativilca Canyon, Northern Peru, Matthew James Montario

Geology Theses and Dissertations

The Peruvian Andes have attained modern elevations of ~4000 m. Many peaks along the drainage divide are in excess of 5500 m with ~2-3 km of vertical relief, and canyons cut into the western edge have up to 3.5 km relief. The Rio Pativilica Canyon is cut into a folded Mesozoic marine sequence intruded by granitic rocks of the Coastal Batholith, which are overlain by Tertiary volcanics: this canyon has relief in excess of ~3 km. Based on geomorphological evidence, two episodes of valley incision cut the Puna erosional surface: 1) The Vallé stage, which is characterized by broad valleys …


Origin And Tectonic Significance Of The Metamorphic Sole And Isolated Dykes Of The Divriği Ophiolite (Sivas, Turkey): Evidence For Slab Break-Off Prior To Ophiolite Emplacement, Osman Parlak, Hüseyi̇n Yilmaz, Durmuş Boztuğ Jan 2006

Origin And Tectonic Significance Of The Metamorphic Sole And Isolated Dykes Of The Divriği Ophiolite (Sivas, Turkey): Evidence For Slab Break-Off Prior To Ophiolite Emplacement, Osman Parlak, Hüseyi̇n Yilmaz, Durmuş Boztuğ

Turkish Journal of Earth Sciences

The Late Cretaceous Divriği ophiolite of east-central Anatolia comprises, from bottom to top, an ophiolitic mélange, metamorphic sole and remnants of oceanic lithosphere. The ophiolitic mélange has been thrust onto the Lower Carboniferous-Campanian Munzur Limestone (Tauride platform), and is in turn tectonically overlain by the metamorphic sole. The metamorphic-sole rocks are represented by amphibolite, plagioclase amphibolite, plagioclase-amphibole schist, plagioclase-epidote-amphibole schist and calc-schist. The oceanic-lithosphere remnant exhibits a complete section, excluding volcanic rocks, comprising mantle tectonites, ultramafic to mafic cumulates, isotropic gabbros and sheeted dykes. Isolated dykes intrude the metamorphic sole and mantle tectonites at different structural levels. The metamorphic-sole rocks …


Mineral-Chemical Constraints On The Miocene Calc-Alkaline And Shoshonitic Volcanic Rocks Of Western Turkey: Disequilibrium Phenocryst Assemblages As Indicators Of Magma Storage And Mixing Conditions, Ercan Aldanmaz Jan 2006

Mineral-Chemical Constraints On The Miocene Calc-Alkaline And Shoshonitic Volcanic Rocks Of Western Turkey: Disequilibrium Phenocryst Assemblages As Indicators Of Magma Storage And Mixing Conditions, Ercan Aldanmaz

Turkish Journal of Earth Sciences

Early to Middle Miocene (22 to 15 Ma) volcanic activity across western Turkey produced a series of lavas and pyroclastic deposits with calc-alkaline and shoshonitic affinities. The erupted magmas show a broad range of compositions from basaltic to rhyolitic (48-75 SiO2 wt%) and are composed of variable phenocryst assemblages. Petrographic and mineral-chemical characteristics suggest that the magmas underwent hydrous crystallization in deep crustal magma chambers that was dominated by plagioclase + pyroxene + pargasitic amphibole fractionation. Subsequent crystallization in shallower magma chambers followed two different trends: (1) anhydrous (pyroxene + plagioclase-dominated); and (2) hydrous (plagioclase + edenitic amphibole + pyroxene-dominated). …


Contact Metamorphism Around The Eocene Saraycık Granodiorite, Eastern Pontides, Turkey, Gülteki̇n Topuz Jan 2006

Contact Metamorphism Around The Eocene Saraycık Granodiorite, Eastern Pontides, Turkey, Gülteki̇n Topuz

Turkish Journal of Earth Sciences

The Eocene Saraycık granodiorite, eastern Pontides, Turkey, is a small post-tectonic intrusive body (~11 km2), cross-cutting tectonically juxtaposed distinct metamorphic and non-metamorphic lithologies. A ~0.8 to 1-km-wide contact-metamorphic aureole has developed around the intrusion. Disequilibrium is prevalent in all lithologies, even in the inner zones of the contact aureole. Conditions of contact metamorphism are estimated by simple phase equilibria applied to microdomains in the metapelitic lithologies without obvious signs of disequilibrium: Shallow emplacement depths (0.21±0.05 GPa = ~5-8 km) are suggested by contact-metamorphic mineral assemblages (e.g., andalusite + corundum + K-feldspar), by Al-in-hornblende barometry on granodiorite and by partial melting …


Mohr-Circle-Based Rotational Invariants Of A Magnetotelluric Data Set From The Thrace Region Of Turkey: Geological Implications, Murat Bayrak, Aysan Gürer, Ö. Feyzi̇ Gürer, O. Meti̇n İlkişik, Ahmet T. Başokur Jan 2006

Mohr-Circle-Based Rotational Invariants Of A Magnetotelluric Data Set From The Thrace Region Of Turkey: Geological Implications, Murat Bayrak, Aysan Gürer, Ö. Feyzi̇ Gürer, O. Meti̇n İlkişik, Ahmet T. Başokur

Turkish Journal of Earth Sciences

In the summer of 1995, magnetotelluric data were acquired at forty sites along a southwest-northeast profile crossing northwestern Turkey in continental Europe. The traverse, 204 km in length, crossed the boundary between a metamorphic mass called the Istranca Massif and a large Tertiary sedimentary basin called the Thrace Basin. The pseudosections of Mohr-circle-based rotational invariant characteristics of the magnetotelluric data such as central impedance (d3), anisotropy angle (l) and phase of central impedance (fd3) were prepared with classical magnetotelluric parameters (apparent resistivity and impedance phase), and detailed Mohr-circle displays were shown for selected stations as a function of the Bostick …


Volcanism And Its Contribution To Mudrock Genesis, Warren Huff Jan 2006

Volcanism And Its Contribution To Mudrock Genesis, Warren Huff

Turkish Journal of Earth Sciences

Explosive eruptions from volcanoes are recorded in the stratigraphic record throughout the Phanerozoic. The most visible evidence of these eruptions is generally in the form of preserved tephra layers, and they appear to be concentrated in the stratigraphic record at times of active plate collision and concomitant high stands of sea level. The products of volcanic eruptions are lavas, tephra and gases, and whereas low-silica, anhydrous basaltic magmas are usually erupted in the form of lava flows high-silica, hydrous rhyolitic magmas are commonly explosively erupted as plinian and ultraplinian plumes, and associated pyroclastic flows. Fallout tephras may be preserved in …


3d-Architecture And Neogene Evolution Of The Malatya Basin: Inferences For The Kinematics Of The Malatya And Ovacık Fault Zones, Nuretdi̇n Kaymakçi, Murat İnceöz, Pinar Ertepinar Jan 2006

3d-Architecture And Neogene Evolution Of The Malatya Basin: Inferences For The Kinematics Of The Malatya And Ovacık Fault Zones, Nuretdi̇n Kaymakçi, Murat İnceöz, Pinar Ertepinar

Turkish Journal of Earth Sciences

The 3D-architecture of the Malatya Basin was studied using remote sensing, seismic interpretation, and palaeostress analysis in the context of the Malatya-Ovacık fault zone. The results indicate that the Ovacık and Malatya fault zones are not different segments of a single 'so called' Malatya-Ovacık fault zone; rather, they are two different fault zones that have operated independently. In addition, the Ovacık fault zone is delimited in the west by the Malatya fault zone, which extends farther north from the point of supposed junction. Maximum individual deflection of streams along the Ovacık fault zone is about 9.3 km, and summation of …


Geochemical Constraints On The Provenance, Mineral Sorting And Subaerial Weathering Of Lower Jurassic And Upper Cretaceous Clastic Rocks Of The Eastern Pontides, Yusufeli (Artvin), Ne Turkey, Abdurrahman Dokuz, Erkan Tanyolu Jan 2006

Geochemical Constraints On The Provenance, Mineral Sorting And Subaerial Weathering Of Lower Jurassic And Upper Cretaceous Clastic Rocks Of The Eastern Pontides, Yusufeli (Artvin), Ne Turkey, Abdurrahman Dokuz, Erkan Tanyolu

Turkish Journal of Earth Sciences

An integrated petrographic and geochemical study of the shales and sandstones of Early Jurassic and Late Cretaceous age in the Yusufeli area (Turkey) was carried out to obtain more information on their provenance, sedimentological history and tectonic setting, as well as to evaluate the influence of weathering, hydraulic sorting and recycling processes upon source-rock signature. Depending on their matrix and mineralogical content, the Lower Jurassic sandstones are identified as arkosic arenite and wacke, while the Upper Cretaceous sandstones are defined as lithic arenite and wacke. Elemental ratios such as La/Sc, Cr/Ni, Co/Th, Th/Sc and Cr/Th indicate a mafic source for …


Calcretized Ferricretes Around The Jaisalmer Area, Thar Desert, India: Their Chemistry, Mineralogy, Micromorphology And Genesis, D. Ramakrishnan, Krishna Chandra Tiwari Jan 2006

Calcretized Ferricretes Around The Jaisalmer Area, Thar Desert, India: Their Chemistry, Mineralogy, Micromorphology And Genesis, D. Ramakrishnan, Krishna Chandra Tiwari

Turkish Journal of Earth Sciences

Ferricrete, an iron duricrust, caps Tertiary and Mesozoic rocks around Jaisalmer in the Indian desert. These ferricretes are associated with two distinct present-day landforms. The upper unit is a high-level dissected, rocky structural plain and the lower one a colluvial flat with soft ferricrete gravels. This study pertains to the first situation wherein field observations, micromorphological features and regolith chemistry suggest an in situ origin for the ferricretes, as in the case of the Walther profile. Subsequent tectonism and changes in base level resulted in a shift in processes from weathering to erosion. Episodes of erosion resulted in inversion of …


Cambrian Stratigraphy And Trilobites Of The Samur Dağ Area, South Of Hakkâri, Southeastern Turkey, William T. Dean Jan 2006

Cambrian Stratigraphy And Trilobites Of The Samur Dağ Area, South Of Hakkâri, Southeastern Turkey, William T. Dean

Turkish Journal of Earth Sciences

Carbonates of the higher Koruk Formation at Yayla Tepe, near the Samur Dağ in southeastern Turkey and about 17 km north of the Iraq border, contain peri-Gondwanan Middle Cambrian trilobites typical of the Mediterranean Subprovince; these comprise at least seven genera and include the easternmost records in the Near and Middle East of Eccaparadoxides and the biozonal genus Pardailhania. In the lower half of the succeeding, largely clastic Seydişehir Formation, Upper Cambrian trilobites from six levels in decalcified limestone interbeds include four new species [Coosinoides parthianus, Elegantaspis? montis, Prochuangia turcica, Taishania bassifrons] in addition to Chuangia? sp. and Palaeadotes sp. …


Palynomorph, Foraminifera, And Calcareous Nannoplankton Biostratigraphy Of Oligo–Miocene Sediments In The Muş Basin, Eastern Anatolia, Turkey, Recep Hayretti̇n Sancay, Zühtü Bati, Uğraş Işik, Sabri̇ Kirici, Ni̇hal Akça Jan 2006

Palynomorph, Foraminifera, And Calcareous Nannoplankton Biostratigraphy Of Oligo–Miocene Sediments In The Muş Basin, Eastern Anatolia, Turkey, Recep Hayretti̇n Sancay, Zühtü Bati, Uğraş Işik, Sabri̇ Kirici, Ni̇hal Akça

Turkish Journal of Earth Sciences

Oligo-Miocene sediments have not been adequately studied biostratigraphically, and a detailed bio-chronostratigraphic framework has not yet been established in Eastern Anatolian basins. Palynomorphs have therefore been correlated with the biozonations of marine dinoflagellates, planktonic foraminifera and calcareous nannoplankton of similar latitudes in combined samples from the Ebulbahar and Kelereşdere measured stratigraphic sections, which are located in the northeastern part of Muş. Palynological (dinoflagellate), foraminiferal micropalaentological, and nannopalaeontological events, correlatable with worldwide defined biozonations, have been documented from uppermost Rupelian to Upper Miocene-Pliocene sediments. First occurrences (FOs) and and last occurrences (LOs) of selected dinoflagellates are important in establishing the biostratigraphic …


Petrography And Geochemistry Of Paragneisses In The Çine Submassif Of The Menderes Massif, Western Anatolia, Firat Şengün, Osman Candan, O. Özcan Dora, O. Ersi̇n Koralay Jan 2006

Petrography And Geochemistry Of Paragneisses In The Çine Submassif Of The Menderes Massif, Western Anatolia, Firat Şengün, Osman Candan, O. Özcan Dora, O. Ersi̇n Koralay

Turkish Journal of Earth Sciences

The Menderes Massif, which covers a large area in western Turkey, is made up of Pan-African basement rocks and a Palaeozoic to Early Tertiary cover sequence. The study area is located in the Dalama and Hallaçlar (Aydın) area, in the northern and central parts of the Çine submassif of the Menderes Massif. The oldest units of the Pan-African basement are metaclastics, consisting of paragneisses and mica schists that gradually and conformably overlay paragneisses. Macroscopic appearances and mineralogical and textural data indicate that paragneisses can be subdivided into four subgroups. These are: (1) black spotted, (2) white spotted, (3) massive, grey-coloured …


Investigation Of Water Masses In İzmir Bay, Western Turkey, Erdem Sayin, İdi̇l Pazi, Canan Eronat Jan 2006

Investigation Of Water Masses In İzmir Bay, Western Turkey, Erdem Sayin, İdi̇l Pazi, Canan Eronat

Turkish Journal of Earth Sciences

The main purpose of this paper is to explore seasonal variability of the local hydrography and investigate the water masses, their seasonal and regional variations in the vicinity of İzmir Bay based on data sets collected between 1994 and 2003. The general water movement characteristics in the bay are provided by CTD data analysis together with Killworth's general circulation model. In the bay, three distinct water masses exist: ASW (Aegean Sea water), IBW (İzmir Bay water) and IBIW (İzmir Bay inner water). Generally, vertically homogenous ASW enters the bay from the north, near Karaburun in winter, and horizontally homogeneous ASW …


Reply To Comment On ‘Petrography And Petrology Of The Calc-Alkaline Sarıhan Granitoid (Ne Turkey): An Example Of Magma Mingling And Mixing’, Zafer Arslan Jan 2006

Reply To Comment On ‘Petrography And Petrology Of The Calc-Alkaline Sarıhan Granitoid (Ne Turkey): An Example Of Magma Mingling And Mixing’, Zafer Arslan

Turkish Journal of Earth Sciences

No abstract provided.


Comment On “Petrography And Petrology Of The Calc-Alkaline Sarıhan Granitoid (Ne Turkey): An Example Of Magma Mingling And Mixing”, Gülteki̇n Topuz, Aral İ. Okay Jan 2006

Comment On “Petrography And Petrology Of The Calc-Alkaline Sarıhan Granitoid (Ne Turkey): An Example Of Magma Mingling And Mixing”, Gülteki̇n Topuz, Aral İ. Okay

Turkish Journal of Earth Sciences

No abstract provided.


Complexity Trends In The Evolutionary History Of Dasycladalean Algae, Michael Stearns Jan 2006

Complexity Trends In The Evolutionary History Of Dasycladalean Algae, Michael Stearns

Senior Honors Theses and Projects

Dasycladalean algae are a group of marine algae that have an excellent fossil record extending back more than 500 million years. In our study, we investigated morphological complexity over the evolutionary history of this group. To determine complexity for each of more than 400 species, we assigned numerical values for six morphological features; the sum for each species forms a quantitative expression of complexity. We found that although maximum complexity increased over time, forms with minimum complexity persisted during most of the evolutionary history of the group.


Geochemical Data For Mercury, Methylmercury, And Other Constituents In Sediments From Englebright Lake, California, 2002, Charles N. Alpers, Michael P. Hunerlach, Mark C. Marvin-Dipasquale, Ronald C. Antweiler, Brenda K. Lasorsa, John F. De Wild, Noah P. Snyder Jan 2006

Geochemical Data For Mercury, Methylmercury, And Other Constituents In Sediments From Englebright Lake, California, 2002, Charles N. Alpers, Michael P. Hunerlach, Mark C. Marvin-Dipasquale, Ronald C. Antweiler, Brenda K. Lasorsa, John F. De Wild, Noah P. Snyder

United States Geological Survey: Publications

This report presents geochemical data from two 2002 sampling campaigns conducted in Englebright Lake on the Yuba River in northern California. A deep coring campaign was done in May–June 2002 and a shallow sampling campaign was completed in October 2002. This work assessed the chemical composition of material deposited in the reservoir between 1940, the year Englebright Dam was completed, and 2002 as part of the Upper Yuba River Studies Program, an effort designed to evaluate the feasibility of introducing anadromous fish, including steelhead and spring-run Chinook salmon, upstream from Englebright Dam. Results of analyses of total mercury (HgT) in …


Distribution Of Boreal Toad Populations In Relation To Estimated Uv-B Dose In Glacier National Park, Montana, Usa, Blake R. Hossack, Stephen A. Diamond, Paul Stephen Corn Jan 2006

Distribution Of Boreal Toad Populations In Relation To Estimated Uv-B Dose In Glacier National Park, Montana, Usa, Blake R. Hossack, Stephen A. Diamond, Paul Stephen Corn

United States Geological Survey: Staff Publications

A recent increase in ultraviolet B radiation is one hypothesis advanced to explain suspected or documented declines of the boreal toad (Bufo boreas Baird and Girard, 1852) across much of the western USA, where some experiments have shown ambient UV-B can reduce embryo survival. We examined B. boreas occupancy relative to daily UV-B dose at 172 potential breeding sites in Glacier National Park, Montana, to assess whether UV-B limits the distribution of toads. Dose estimates were based on ground-level UV-B data and the effects of elevation, local topographic and vegetative features, and attenuation in the water column. We also …


Divergent Patterns Of Abundance And Age-Class Structure Of Headwater Stream Tadpoles In Burned And Unburned Watersheds, Blake R. Hossack, Paul Stephen Corn, Daniel B. Fagre Jan 2006

Divergent Patterns Of Abundance And Age-Class Structure Of Headwater Stream Tadpoles In Burned And Unburned Watersheds, Blake R. Hossack, Paul Stephen Corn, Daniel B. Fagre

United States Geological Survey: Staff Publications

Wildfire is a potential threat to many species with narrow environmental tolerances like the Rocky Mountain tailed frog (Ascaphlls montanlls Mittleman and Myers, 1949), which inhabits a region where the frequency and intensity of wildfires are expected to increase. We compared pre- and post-fire counts of tadpoles in eight streams in northwestem Montana to determine the effects of wildfire on A. montanus. All streams were initially sampled in 2001, 2 years before four of them bumed in a large wildfire, and were resampled during the 2 years follo\ving the fire. Counts of tadpoles were similar in the 1\\'0 …