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Groundwater Investigation Buntine-Marchagee Natural Diversity Recovery Catchment, Russell John Speed, M Strelein Jan 2004

Groundwater Investigation Buntine-Marchagee Natural Diversity Recovery Catchment, Russell John Speed, M Strelein

Resource management technical reports

A groundwater investigation was initiated in the Buntine-Marchagee Natural Diversity Recovery Catchment 200 kms north-east of Perth, Western Australia in 2002. The investigation aimed to install a regional groundwater monitoring network and characterise the regolith throughout the catchment. Drill site selection was based on establishing a series of transects to enable construction of hydrogeological cross-sections to enhance conceptual understanding of the catchment.


Experimental Determination Of Stiffness Of Joints In Welded Tuff, Jaak J.K. Daemen, George Danko, Amy J. Smiecinski Jan 2004

Experimental Determination Of Stiffness Of Joints In Welded Tuff, Jaak J.K. Daemen, George Danko, Amy J. Smiecinski

Publications (YM)

Fourteen uniaxial joint compression tests were run to determine the normal and shear stiffnesses of type 1 fracture joints (healed joints filled with vapor-phase mineral deposits) obtained from the Yucca Mountain site. The uniaxial joint compression results show that these joints behave linearly up to over 85% of their loading history. They are stiff with strengths very close to the strength of the intact rock. Five direct shear tests were run on open, separated, joints. Results obtained from the direct shear testing show that the normal stiffness increases with increasing normal stress. Shearing through asperities gives high joint shear stiffness …


National Water Quality Inventory: Report To Congress 2004 Reporting Cycle Jan 2004

National Water Quality Inventory: Report To Congress 2004 Reporting Cycle

United States Environmental Protection Agency: Publications

Table of Contents

Section Page

List of Figures.............................................................................................................................iv List of Tables...............................................................................................................................iv List of Acronyms..........................................................................................................................v Executive Summary..........................................................................................................................1

I. Background...................................................................................................................5

About the Water Quality Assessment and TMDL Information Database (ATTAINS)..........................................................................................................................5

Assessing Water Quality................................................................................................................................7

II. Findings.......................................................................................................................13 Rivers and Streams...........................................................................................................................13 Lakes, Ponds, and Reservoirs.......................................................................................................................16

Bays and Estuaries.........................................................................................................................20 Other Waters..............................................................................................................................23 Coastal Resources.......................................................................................................................23

Great Lakes.....................................................................................................................24 Wetlands..........................................................................................................................24

III. Probability Surveys of Water Quality.......................................................................26

National Coastal Assessment....................................................................................26

The Wadeable Streams Assessment.......................................................................27

Survey of the Nation’s Lakes.......................................................................................29

National Rivers and Streams Assessment.............................................................30

National Wetland Condition Assessment...............................................................30

State-Scale Statistical Surveys..................................................................................31

South Carolina..............................................................................................................32 Indiana............................................................................................................................33 Florida.............................................................................................................................34 IV. Future Reporting......................................................................................................36

V. References………………………………………………………………………….37


Sediment Grain-Size And Loss-On-Ignition Analyses From 2002 Englebright Lake Coring And Sampling Campaigns, Noah P. Snyder, James R. Allen, Carlin Dare, Margaret A. Hampton, Gary Schneider, Ryan J. Wooley, Charles N. Alpers, Mark C. Marvin-Dipasquale Jan 2004

Sediment Grain-Size And Loss-On-Ignition Analyses From 2002 Englebright Lake Coring And Sampling Campaigns, Noah P. Snyder, James R. Allen, Carlin Dare, Margaret A. Hampton, Gary Schneider, Ryan J. Wooley, Charles N. Alpers, Mark C. Marvin-Dipasquale

United States Geological Survey: Publications

This report presents sedimentologic data from three 2002 sampling campaigns conducted in Englebright Lake on the Yuba River in northern California. This work was done to assess the properties of the material deposited in the reservoir between completion of Englebright Dam in 1940 and 2002, as part of the Upper Yuba River Studies Program. Included are the results of grain-size-distribution and loss-on-ignition analyses for 561 samples, as well as an error analysis based on replicate pairs of subsamples.


Geochemical Characterization Of Water, Sediment, And Biota Affected By Mercury Contamination And Acidic Drainage From Historical Gold Mining, Greenhorn Creek, Nevada County, California, 1999-2001, Charles N. Alpers, Michael P. Hunerlach, Jason T. May, Roger L. Hothem, Howard E. Taylor, Ronald C. Antweiler, John F. De Wild, David A. Lawler Jan 2004

Geochemical Characterization Of Water, Sediment, And Biota Affected By Mercury Contamination And Acidic Drainage From Historical Gold Mining, Greenhorn Creek, Nevada County, California, 1999-2001, Charles N. Alpers, Michael P. Hunerlach, Jason T. May, Roger L. Hothem, Howard E. Taylor, Ronald C. Antweiler, John F. De Wild, David A. Lawler

United States Geological Survey: Publications

In 1999, the U.S. Geological Survey (USGS) initiated studies of mercury and methylmercury occurrence, transformation, and transport in the Bear River and Yuba River watersheds of the northwestern Sierra Nevada. Because these watersheds were affected by large-scale, historical gold extraction using mercury amalgamation beginning in the 1850s, they were selected for a pilot study of mercury transport by the USGS and other cooperating agencies. This report presents data on methylmercury (MeHg) and total mercury (THg) concentrations in water, bed sediment, invertebrates, and frogs collected at 40 stations during 1999−2001 in the Greenhorn Creek drainage, a major tributary to the Bear …


Stable Hydrogen Isotope Analysis Of Bat Hair As Evidence For Seasonal Molt And Long-Distance Migration, Paul M. Cryan, Michael A. Bogan, Robert O. Rye, Gary P. Landis, Cynthia L. Kester Jan 2004

Stable Hydrogen Isotope Analysis Of Bat Hair As Evidence For Seasonal Molt And Long-Distance Migration, Paul M. Cryan, Michael A. Bogan, Robert O. Rye, Gary P. Landis, Cynthia L. Kester

United States Geological Survey: Staff Publications

Although hoary bats (Lasiurus cinereus) are presumed to be migratory and capable of long-distance dispersal, traditional marking techniques have failed to provide direct evidence of migratory movements by individuals. We measured the stable hydrogen isotope ratios of bat hair (∂Dh) and determined how these values relate to stable hydrogen isotope ratios of precipitation (∂Dp). Our results indicate that the major assumptions of stable isotope migration studies hold true for hoary bats and that the methodology provides a viable means of determining their migratory movements. We present evidence that a single annual molt occurs in L. cinereus …


Genetic Structure Of Cougar Populations Across The Wyoming Basin: Metapopulation Or Megapopulation, Charles R. Anderson Jr., Federick G. Lindzey, David B. Mcdonald Jan 2004

Genetic Structure Of Cougar Populations Across The Wyoming Basin: Metapopulation Or Megapopulation, Charles R. Anderson Jr., Federick G. Lindzey, David B. Mcdonald

United States Geological Survey: Staff Publications

We examined the genetic structure of 5 Wyoming cougar (Puma concolor) populations surrounding the Wyoming Basin, as well as a population from southwestern Colorado. When using 9 microsatellite DNA loci, observed heterozygosity was similar among populations (HO = 0.49–0.59) and intermediate to that of other large carnivores. Estimates of genetic structure (FST = 0.028, RST = 0.029) and number of migrants per generation (Nm) suggested high gene flow. Nm was lowest between distant populations and highest among adjacent populations. Examination of these data, plus Mantel test results of genetic versus geographic distance (P ≤ 0.01), suggested both isolation …


New Distributional Record Of The Nothern Redbelly Dace In The Northern Great Plains, Nathan M. Morey, Charles R. Berry Jr. Jan 2004

New Distributional Record Of The Nothern Redbelly Dace In The Northern Great Plains, Nathan M. Morey, Charles R. Berry Jr.

United States Geological Survey: Staff Publications

The range of the northern redbelly dace (Phoxinus eos) is grouped into two regions in central North America (Stasiak 1980). In the northern Great Plains, the species is distributed throughout the upper Missouri River drainage in Montana and Canada (Brown 1971, Scott and Crossman 1973). In the Central Lowlands, the northern redbelly dace is distributed through northern Minnesota, Wisconsin, Canada, and the Great Lakes region (Hubbs and Cooper 1936, Eddy and Underhill 1976, Becker 1983). The present distribution of northern redbelly dace has shifted northward from a more southerly distribution during Pleistocene glaciation (Cross et al. 1986). Relict …


Mineralogical Maturity In Dunefields Of North America, Africa And Australia, Daniel R. Muhs Jan 2004

Mineralogical Maturity In Dunefields Of North America, Africa And Australia, Daniel R. Muhs

United States Geological Survey: Staff Publications

Studies of dunefields in central and western North America show that mineralogical maturity can provide new insights into the origin and evolution of aeolian sand bodies. Many of the world’s great sand seas in Africa, Asia and Australia are quartz-dominated and thus can be considered to be mineralogically mature. The Algodones (California) and Parker (Arizona) dunes in the southwestern United States are also mature, but have inherited a high degree of mineralogical maturity from quartz-rich sedimentary rocks drained by the Colorado River. In Libya, sediments of the Zallaf sand sea, which are almost pure quartz, may have originated in a …


Reproduction And Seasonal Activity Of Silver-Haired Bats In Western Nebraska, Keith Geluso, Jeffrey J. Huebschman, Jeremy A. White, Michael A. Bogan Jan 2004

Reproduction And Seasonal Activity Of Silver-Haired Bats In Western Nebraska, Keith Geluso, Jeffrey J. Huebschman, Jeremy A. White, Michael A. Bogan

United States Geological Survey: Staff Publications

Silver-haired bats (Lasionycteris noctivagans) were thought only to migrate through Nebraska; however, recent surveys in eastern Nebraska report summer records of females and their young. Our study in western Nebraska also shows that silver-haired bats are summer residents. We discovered the 1st reproductively active L. noctivagans in this part of the state. We caught lactating females and volant young in riparian forests along the North Platte River and in forested areas of the Pine Ridge. Previously, adult males were not known from Nebraska in summer, and only 4 records of L. noctivagans were known from western Nebraska during …


Corrigendum To ‘‘Radiocarbon Dating, Chronologic Framework, And Changes In Accumulation Rates Of Holocene Estuarine Sediments From Chesapeake Bay’’ [Quaternary Research 57 (2002) 58–70], Steven M. Colman, Pattie C. Baucom, John F. Bratton, Thomas M. Cronin, John P. Mcgeehin, Debra Willard, Andrew R. Zimmerman, Peter R. Vogt Jan 2004

Corrigendum To ‘‘Radiocarbon Dating, Chronologic Framework, And Changes In Accumulation Rates Of Holocene Estuarine Sediments From Chesapeake Bay’’ [Quaternary Research 57 (2002) 58–70], Steven M. Colman, Pattie C. Baucom, John F. Bratton, Thomas M. Cronin, John P. Mcgeehin, Debra Willard, Andrew R. Zimmerman, Peter R. Vogt

United States Geological Survey: Staff Publications

Because of an error in the calculation of bulk densities from water contents, the cumulative masses in Fig. 8 are too high by a factor of about 2. The actual correction depends to small degree on water content and ranges from 1.8 for a water content of 50% to 2.2 for a water content of 75%. The values for mass accumulation rates in the left two columns of Table 5 are also affected, but the ratios between pre- and post-settlement times are not. A revised version of that table is given below. None of the major conclusions of the paper …


Record Of Late Pleistocene Glaciation And Deglaciation In The Southern Cascade Range. I. Petrological Evidence From Lacustrine Sediment In Upper Klamath Lake, Southern Oregon, Richard L. Reynolds, Joseph G. Rosenbaum, Josh Rapp, Michael W. Kerwin, J. Platt Bradbury, David Adam, Steven Colman Jan 2004

Record Of Late Pleistocene Glaciation And Deglaciation In The Southern Cascade Range. I. Petrological Evidence From Lacustrine Sediment In Upper Klamath Lake, Southern Oregon, Richard L. Reynolds, Joseph G. Rosenbaum, Josh Rapp, Michael W. Kerwin, J. Platt Bradbury, David Adam, Steven Colman

United States Geological Survey: Staff Publications

Petrological and textural properties of lacustrine sediments from Upper Klamath Lake, Oregon, reflect changing input volumes of glacial flour and thus reveal a detailed glacial history for the southern Cascade Range between about 37 and 15 ka. Magnetic properties vary as a result of mixing different amounts of the highly magnetic, glacially generated detritus with less magnetic, more weathered detritus derived from unglaciated parts of the large catchment. Evidence that the magnetic properties record glacial flour input is based mainly on the strong correlation between bulk sediment particle size and parameters that measure the magnetite content and magnetic mineral freshness. …


Introduction To Special Section: Preparing For The San Andreas Fault Observatory At Depth, Stephen Hickman, Mark D. Zoback, William Ellsworth Jan 2004

Introduction To Special Section: Preparing For The San Andreas Fault Observatory At Depth, Stephen Hickman, Mark D. Zoback, William Ellsworth

United States Geological Survey: Staff Publications

The San Andreas Fault Observatory at Depth (SAFOD) is a comprehensive project to drill into the hypocentral zone of repeating M ~ 2 earthquakes on the San Andreas Fault at a depth of about 3 km. The goals of SAFOD are to establish a multi-stage geophysical observatory in close proximity to these repeating earthquakes, to carry out a comprehensive suite of downhole measurements in order to study the physical and chemical conditions under which earthquakes occur and to exhume rock and fluid samples for extensive laboratory studies. In the vicinity of SAFOD, the San Andreas is moving through a combination …


Estimating Accumulation Rates And Physical Properties Of Sediment Behind A Dam: Englebright Lake, Yuba River, Northern California, Noah P. Snyder, David M. Rubin, Charles N. Alpers, Jonathan R. Childs, Jennifer A. Curtis, Lorraine E. Flint, Scott A. Wright Jan 2004

Estimating Accumulation Rates And Physical Properties Of Sediment Behind A Dam: Englebright Lake, Yuba River, Northern California, Noah P. Snyder, David M. Rubin, Charles N. Alpers, Jonathan R. Childs, Jennifer A. Curtis, Lorraine E. Flint, Scott A. Wright

United States Geological Survey: Staff Publications

Studies of reservoir sedimentation are vital to understanding scientific and management issues related to watershed sediment budgets, depositional processes, reservoir operations, and dam decommissioning. Here we quantify the mass, organic content, and grain-size distribution of a reservoir deposit in northern California by two methods of extrapolating measurements of sediment physical properties from cores to the entire volume of impounded material. Englebright Dam, completed in 1940, is located on the Yuba River in the Sierra Nevada foothills. A research program is underway to assess the feasibility of introducing wild anadromous fish species to the river upstream of the dam. Possible management …


Mercury And Methylmercury Concentrations And Loads In The Cache Creek Watershed, California, Joseph L. Domagalski, Charles N. Alpers, Darell G. Slotton, Thomas H. Suchanek, Shaun M. Ayers Jan 2004

Mercury And Methylmercury Concentrations And Loads In The Cache Creek Watershed, California, Joseph L. Domagalski, Charles N. Alpers, Darell G. Slotton, Thomas H. Suchanek, Shaun M. Ayers

United States Geological Survey: Staff Publications

Concentrations and loads of total mercury and methylmercury were measured in streams draining abandoned mercury mines and in the proximity of geothermal discharge in the Cache Creek watershed of California during a 17-month period from January 2000 through May 2001. Rainfall and runoff were lower than long-term averages during the study period. The greatest loading of mercury and methylmercury from upstream sources to downstream receiving waters, such as San Francisco Bay, generally occurred during or after winter rainfall events. During the study period, loads of mercury and methylmercury from geothermal sources tended to be greater than those from abandoned mining …


An Association Of Benthic Foraminifera And Gypsum In Holocene Sediments Of Estuarine Chesapeake Bay, Usa, John Cann, Thomas Cronin Jan 2004

An Association Of Benthic Foraminifera And Gypsum In Holocene Sediments Of Estuarine Chesapeake Bay, Usa, John Cann, Thomas Cronin

United States Geological Survey: Staff Publications

Two cores of Holocene sediments recovered from the Cape Charles Channel of Chesapeake Bay yielded radiocarbon ages of about 6.8 to 5.8 ka for the lower intervals. Fossil foraminifera preserved in these lower sediments are dominated by species of Elphidium, which make up about 90% of the assemblage throughout, and probably signify deposition in hypersaline waters. Buccella frigida and Ammonia beccarii are the only other species commonly present. Hypersalinity of bottom waters seems to have been maintained by water-density stratification in a basin-like section of the channel. In core PTXT -4-P-I transition to modem Chesapeake conditions, in which numbers …


Chronology Of Sediment Deposition In Upper Klamath Lake, Oregon, Steven M. Colman, J. Platt Bradbury, John P. Mcgeehin, Charles W. Holmes, David Edginton, Andrei M. Sarna-Wojcicki Jan 2004

Chronology Of Sediment Deposition In Upper Klamath Lake, Oregon, Steven M. Colman, J. Platt Bradbury, John P. Mcgeehin, Charles W. Holmes, David Edginton, Andrei M. Sarna-Wojcicki

United States Geological Survey: Staff Publications

A combination of tephrochronology and 14C, 210Pb, and 137Cs measurements provides a robust chronology for sedimentation in Upper Klamath Lake during the last 45 000 years. Mixing of surficial sediments and possible mobility of the radio-isotopes limit the usefulness of the 137Cs and 210Pb data, but 210Pb profiles provide reasonable average sediment accumulation rates for the last 100–150 years. Radiocarbon ages near the top of the core are somewhat erratic and are too old, probably as a result of detrital organic carbon, which may have become a more common component in recent times as …


Limnological And Climatic Environments At Upper Klamath Lake, Oregon During The Past 45 000 Years, J. Platt Bradbury, Steven M. Colman, Walter E. Dean Jan 2004

Limnological And Climatic Environments At Upper Klamath Lake, Oregon During The Past 45 000 Years, J. Platt Bradbury, Steven M. Colman, Walter E. Dean

United States Geological Survey: Staff Publications

Upper Klamath Lake, in south-central Oregon, contains long sediment records with well-preserved diatoms and lithological variations that reflect climate-induced limnological changes. These sediment archives complement and extend high resolution terrestrial records along a north–south transect that includes areas influenced by the Aleutian Low and Subtropical High, which control both marine and continental climates in the western United States. The longest and oldest core collected in this study came from the southwest margin of the lake at Caledonia Marsh, and was dated by radiocarbon and tephrochronology to an age of about 45 ka. Paleolimnological interpretations of this core, based upon geochemical …


Grassland Vegetation And Bird Communities In The Southern Great Plains Of North America, Robert N. Chapman, David M. Engle, Ronald E. Masters, David M. Leslie Jr. Jan 2004

Grassland Vegetation And Bird Communities In The Southern Great Plains Of North America, Robert N. Chapman, David M. Engle, Ronald E. Masters, David M. Leslie Jr.

United States Geological Survey: Staff Publications

Structure and composition of vegetation and abundance of breeding birds in grasslands seeded to Old World bluestem (Bothriochloa ischmaeum) were compared to native mixed prairie in the southern Great Plains of North America. Abundance of birds was determined using fixed-radius point counts. Detrended correspondence analysis was used to compare plant community composition and canonical correspondence analysis was used to examine the relationships between plant species composition and vegetation structure with the bird community. Plant species composition differed distinctly between seeded grassland and native mixed prairie, but the differences were not reflected in habitat structure, bird community composition, or …


The Karakaya Complex: A Review Of Data And Concepts, Aral İ. Okay, M. Cemal Göncüoğlu Jan 2004

The Karakaya Complex: A Review Of Data And Concepts, Aral İ. Okay, M. Cemal Göncüoğlu

Turkish Journal of Earth Sciences

The Karakaya Complex in the Pontides consists of highly deformed and partly metamorphosed clastic and volcanic series of Permian and Triassic age. It is generally subdivided into two parts: The structurally lower part, called the Lower Karakaya Complex, consists of a mafic lava-mafic pyroclastite-shale-limestone succession metamorphosed in the greenschist and blueschist facies during the Late Palaeozoic or Triassic. The structurally upper part is made up of highly deformed Permian and Triassic clastic, volcaniclastic and volcanic rocks with exotic limestone blocks. There are currently two different models for the depositional setting and tectonic evolution of the Karakaya Complex. The rift model …


Significance Of The Volcanogenic Nilüfer Unit And Related Components Of The Triassic Karakaya Complex For Tethyan Subduction/Accretion Processes In Nw Turkey, Elizabeth A. Pickett, Alastair H. F. Robertson Jan 2004

Significance Of The Volcanogenic Nilüfer Unit And Related Components Of The Triassic Karakaya Complex For Tethyan Subduction/Accretion Processes In Nw Turkey, Elizabeth A. Pickett, Alastair H. F. Robertson

Turkish Journal of Earth Sciences

The Tethyan Karakaya Complex extends east-west across northern Turkey from the Aegean coast to Iran (c. 1100 km), and is interpreted as a Mid-Late Triassic subduction/accretion complex. It comprises strongly deformed fragments of Triassic oceanic seamounts, mid-ocean ridge-type oceanic crust, trench-type sedimentary rocks (Ortaoba Unit) and Permian-Triassic continental fragments (Çal Unit). We focus on the Triassic Nilüfer Unit, which comprises altered basic volcanic and volcaniclastic rocks, volcanogenic sedimentary rocks, heterogeneous debris flow deposits, calciturbidites, siliceous pelagic sedimentary rocks and, in places, Triassic shallow-water limestones. The predominant lithologies are massive basalt and reworked basic pyroclastic deposits. Additional detrital lithologies include volcanogenic …


Geology And Correlation Of The Ezine Zone: A Rhodope Fragment In Nw Turkey?, Laurent Beccaletto, Catherine Jenny Jan 2004

Geology And Correlation Of The Ezine Zone: A Rhodope Fragment In Nw Turkey?, Laurent Beccaletto, Catherine Jenny

Turkish Journal of Earth Sciences

In northwestern Turkey, the Denizgören ophiolite and its sedimentary substratum, the Ezine Group, are enigmatic geological objects whose evolution remains problematic. Based on long-term fieldwork, we here propose a solution for their genesis and correlation. The whole of the Ezine Group, more than three km thick, is characterised by the systematic occurrence of carbonate rocks in the greenschist facies. It has been subdivided into three conformable formations: the Geyikli Formation, with a slight terrigeneous detrital nature, (Middle)-Late Permian in age; the Karadağ Formation, with platform-type sedimentation with local detrital input, Late Permian (Djulfian) in age; the Çamköy Formation, with a …


New Results On The Lithostratigraphy Of The Kazdağ Massif In Northwest Turkey, Mehmet Duru, Şükrü Pehli̇van, Yalçin Şentürk, Fatma Yavaş, Hüseyi̇n Kar Jan 2004

New Results On The Lithostratigraphy Of The Kazdağ Massif In Northwest Turkey, Mehmet Duru, Şükrü Pehli̇van, Yalçin Şentürk, Fatma Yavaş, Hüseyi̇n Kar

Turkish Journal of Earth Sciences

The high-grade metamorphic rocks of the Kazdağ mountain range, termed the Kazdağ Group, crop out as a tectonic window under the Karakaya Complex in northwestern Turkey. The Kazdağ Group forms a doubly plunging, NE-SW-trending anticliniorium. During our regional geological mapping of the Kazdağ Group, we have subdivided the metamorphic rocks into four formations. The lowermost unit is the Fındıklı formation, which comprises amphibole-gneiss, marble and minor amphibolite. It crops out mainly in the southern part of the Kazdağ Massif. The marble horizons within the Fındıklı formation have been named the Altınoluk and Babadağ marble members. The overlying unit, comprising metadunite …


Uppermost Triassic Limestone In The Karakaya Complex- Stratigraphic And Tectonic Significance, Aral İ. Okay, Demi̇r Altiner Jan 2004

Uppermost Triassic Limestone In The Karakaya Complex- Stratigraphic And Tectonic Significance, Aral İ. Okay, Demi̇r Altiner

Turkish Journal of Earth Sciences

Two important tectonostratigraphic units of the Karakaya Complex in northwest Turkey are: a lower metamorphic sequence of metabasite, phyllite and marble, called the Nilüfer Unit; and an upper clastic sequence with Permian and Carboniferous limestone olistoliths called the Hodul Unit. In northwestern Turkey, the Hodul Unit consists of arkosic sandstones, which pass upward into greywacke and siltstone with Permian and Carboniferous limestone blocks. A scarce macrofauna in the sandstones indicates a Norian age for the Hodul Unit. We report for the first time Norian-Rhaetian limestones, here named the Kaşal Limestone Member, from the Hodul Unit to the southwest of Balıkesir. …


Upper Permian (Changxingian) Radiolarian Cherts Within The Clastic Successions Of The "Karakaya Complex" In Nw Anatolia, M. Cemal Göncüoğlu, Kiyoko Kuwahara, U. Kağan Teki̇n, Necati̇ Turhan Jan 2004

Upper Permian (Changxingian) Radiolarian Cherts Within The Clastic Successions Of The "Karakaya Complex" In Nw Anatolia, M. Cemal Göncüoğlu, Kiyoko Kuwahara, U. Kağan Teki̇n, Necati̇ Turhan

Turkish Journal of Earth Sciences

The arkosic sandstones with olistostromes within the "Karakaya Complex" in NW Anatolia to the south of Geyve include a thin layer of green chert with radiolaria. Based on the composition of Albaillellids, the radiolarian assemblage corresponds to the Neoalbaillella ornithoformis assemblage, and its age is assigned to the Changxingian (Late Permian). This is the first finding of synsedimentary radiolarian cherts within the Karakaya units and the indication of latest Permian rifting of the Karakaya basin within the Midian carbonate platform and its pre-Permian basement in the Sakarya Composite Terrane.


Autochthonous Upper Permian (Midian) Carbonates In The Western Sakarya Composite Terrane, Geyve Area, Turkey: Preliminary Data, Necati̇ Turhan, Cengi̇z Okuyucu, M. Cemal Göncüoğlu Jan 2004

Autochthonous Upper Permian (Midian) Carbonates In The Western Sakarya Composite Terrane, Geyve Area, Turkey: Preliminary Data, Necati̇ Turhan, Cengi̇z Okuyucu, M. Cemal Göncüoğlu

Turkish Journal of Earth Sciences

Permian limestones occur widely within the clastic units of the "Karakaya Complex" and are interpreted as allochthonous bodies or olistoliths. In the Kadirler area to the south of Geyve, however, Upper Permian (Midian) quartz sandstones and carbonates with a rich foraminifer fauna disconformably overlie a crystalline basement complex. This basement complex comprises metaclastic rocks, recrystallised limestones, metacherts, and metadiabases, and is intruded by granodiorites. The overlying basal conglomerates and quartzitic sandstones are dominated by pebbles from the basement complex and are followed upward by medium- to thick-bedded dolomites, dolomitic limestones and limestones. The foraminiferal assemblage with Neoschwagerina haydeni Dutkevitch and …


Geology And Structural Evolution Of The Tokat Massif (Eastern Pontides, Turkey), Ali̇ Yilmaz, Hüseyi̇n Yilmaz Jan 2004

Geology And Structural Evolution Of The Tokat Massif (Eastern Pontides, Turkey), Ali̇ Yilmaz, Hüseyi̇n Yilmaz

Turkish Journal of Earth Sciences

The Tokat Massif consists of a pre-Jurassic metamorphic complex that crops out widely between Amasya and Reşadiye in the western part of eastern Pontides, and which can be correlated with the Karakaya Complex of the western Pontides. This complex is named the Tokat Group, and is divided into two main units, namely, the Turhal Metamorphics and Devecidağ Mélange. The Turhal Metamorphics form a volcano-sedimentary sequence in the northern part of the Tokat Massif. The lower level of the formation is made up of gneiss, amphibolite and mica schists, whereas the upper part is represented by an alternation of mica schist, …


Field, Petrographic And Geochemical Characteristics Of The Hamit Alkaline Intrusion In The Central Anatolian Crystalline Complex, Turkey, Nurdane İlbeyli̇ Jan 2004

Field, Petrographic And Geochemical Characteristics Of The Hamit Alkaline Intrusion In The Central Anatolian Crystalline Complex, Turkey, Nurdane İlbeyli̇

Turkish Journal of Earth Sciences

The Hamit pluton is one of the alkaline intrusions in the Central Anatolian Crystalline Complex (CACC). The pluton consists of nepheline syenite, pseudoleucite syenite, alkali-feldspar syenite and quartz syenite. The nepheline syenite and pseudoleucite syenite are cut by foid-bearing microsyenitic dykes, whereas the alkali-feldspar syenite and quartz syenite are cut by aplitic and silicic dykes. The predominantly peralkaline Hamit intrusive rocks possess field, petrographic and geochemical characteristics comparable to A-type granites. All intrusive rocks of this pluton show enrichment in LILE and LREE relative to HFSE. The Th/Yb versus Ta/Yb plot suggests that the intrusive rocks formed from an enriched …


Magma Interaction Recorded In Plagioclase Zoning In Granitoid Systems, Zigana Granitoid, Eastern Pontides, Turkey, Orhan Karsli, Faruk Aydin, M. Burhan Sadiklar Jan 2004

Magma Interaction Recorded In Plagioclase Zoning In Granitoid Systems, Zigana Granitoid, Eastern Pontides, Turkey, Orhan Karsli, Faruk Aydin, M. Burhan Sadiklar

Turkish Journal of Earth Sciences

Plagioclase crystals characterized by compositional zoning are typical of the Zigana Granitoid (ZG), NE Turkey. The zoned crystals, which show textural equilibrium with the assemblage quartz + plagioclase + K-feldspar + hornblende + biotite + pyroxene + magnetite + ilmenite, exhibit oscillatory zoning. The zoned plagioclase crystals, ranging in size from 3 to 6 mm, are oval and larger than normal lath-shaped crystals. The zoned crystals are divided petrographically into two main types: (i) crystals zones only at their rims, with spongy cores; and (ii) completely zoned ones. Composition of the zoned crystals ranges from An_{23} (oligoclase) to An_{70} (labradorite). …


Agricultural Sub-Regions Of The Avon River Basin, Paul D. Galloway Jan 2004

Agricultural Sub-Regions Of The Avon River Basin, Paul D. Galloway

Resource management technical reports

This report identifies, describes and locates nine sub-regions within the land cleared for agricultural uses in the Avon River Basin in Western Australia. The sub-regions are: Darling Range; Dale/Upper Avon; Avon Valley; Yealering Lakes; Mortlock; Northern Sandplain; south-east Lakes; Carrabin; Southern Cross. The sub-regions are described in terms of their distinguishing biophysical characteristics of: soils and related original vegetative cover; general topography; surface and sub-surface hyrdological stus; underlying geology; and rainfall and evapotranspiration range. Current dominant land use, economic drivers and land use pressures are identified for each sub-region.