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Ground Motion For The Maximum Credible Earthquake In Kentucky, Zhenming Wang Jan 2010

Ground Motion For The Maximum Credible Earthquake In Kentucky, Zhenming Wang

Report of Investigations--KGS

Although they are not frequent, earthquakes occur in and around Kentucky and pose certain hazards. Assessing seismic hazards is challenging, however, because of a lack of observations. The best estimates of ground motions that could be expected if the maximum credible earthquake occurs in or around Kentucky are depicted in maps showing peak ground acceleration and short-period (0.2 second) and long-period (1.0 second) response accelerations with 5 percent critical damping on hard rock. Another consideration for seismic safety is that the maximum credible earthquake has a long recurrenece interval, from 500 to 1,000 years in the New Madrid Seismic Zone …


Development Of A Spectral 2-D Fast Fourier Transform Analysis For Sand Ripple Morphology Interpretation, Christopher M. Englert Jan 2010

Development Of A Spectral 2-D Fast Fourier Transform Analysis For Sand Ripple Morphology Interpretation, Christopher M. Englert

Honors Theses

A MATLAB-based 2-Dimensional Fast Fourier Transform spectral analysis is developed and tested for its applicability to bedform morphology and hydrodynamic data from a hydrodynamically complex field site. The aspects of the procedure tested are (1) the use of an 8 sub-region arrangement for analysis versus five other arrangements, (2) the procedure for averaging the wavelength-and-orientation outputs from each sub-region to produce a single representative value for each image, (3) methods for eliminating and/or filtering poor quality data, and (4) the procedural steps in the spectral analysis that can appropriately incorporate automation versus manual involvement and interpretation. The automated technique is …


Late Permian Paleoenvironmental Factors Expounded Through Analysis Of A Forest-Floor Paleosol Profile, Karoo Basin, South Africa, Cassi Knight Jan 2010

Late Permian Paleoenvironmental Factors Expounded Through Analysis Of A Forest-Floor Paleosol Profile, Karoo Basin, South Africa, Cassi Knight

Honors Theses

Beaufort Group paleosols from the Karoo Basin, South Africa, record the paleoenvironmental conditions that existed prior to and after the Permian-Triassic extinction event. Paleosol exposures from Wapadsberg Pass, Eastern Cape Province, represent a well- preserved forest-floor litter overlying an interpreted inceptisol, a condition unique to the basin. Vegetation that colonized this landscape included a canopy of the gymnosperm Glossopteris and an understory of sphenopsids (Phyllotheca and Trizygia). Wapadsberg Pass paleosol sites were sampled for petrographic and geochemical analyses to constrain interpretations of Late Permian paleoenvironmental conditions that existed ~ 70 m below the Permian-Triassic Boundary (PTB). This project focuses on …


Lithium- And Oxygen- Isotope Profiles Of A Mid-Atlantic Ridge Oceanic Core Complex: The Atlantis Massif, 30°N, Ellen J. Crapster-Pregont Jan 2010

Lithium- And Oxygen- Isotope Profiles Of A Mid-Atlantic Ridge Oceanic Core Complex: The Atlantis Massif, 30°N, Ellen J. Crapster-Pregont

Honors Theses

Oxygen (O) and lithium (Li) are fluid-mobile elements used as geochemical tracers of a crustal component in the mantle. The isotopes of each element fractionate according to the degree and temperature of hydrothermal alteration. Previous studies demonstrate that Li and O isotopic trends are coupled within the upper crust near mid-ocean ridges but are decoupled in subduction-related volcanism. To better understand the average crustal signature of these systems, it is necessary to characterize these systems in the presently poorly understood lower oceanic crust. This study uses lower crustal samples from IODP Expedition 305 Hole U1309D exhumed at the Atlantis Massif, …


Soil Water And Crop Growth Processes In A Farmer's Field, Susmitha Surendran Nambuthiri Jan 2010

Soil Water And Crop Growth Processes In A Farmer's Field, Susmitha Surendran Nambuthiri

University of Kentucky Doctoral Dissertations

The study was aimed to provide information on local biomass development during crop growth using ground based optical sensors and to incorporate the local crop status to a crop growth simulation model to improve understanding on inherent variability of crop field. The experiment was conducted in a farmer’s field located near Princeton in Caldwell County, Western Kentucky. Data collection on soil, crop and weather variables was carried out in the farm from 2006 December to 2008 October. During this period corn (Zea mays L.) and winter wheat (Triticum sp) were grown in the field. A 450 m …


Ground Penetrating Radar Investigations In Upper Kama Potash Mines, Oleg N. Kovin Jan 2010

Ground Penetrating Radar Investigations In Upper Kama Potash Mines, Oleg N. Kovin

Doctoral Dissertations

"An understanding of the structure and state of the rock mass surrounding underground openings in the potash mines is critically important for safe mining, planning the methods of extraction of an orebody, and preventing the influx of ground water. Continuous common offset ground penetrating radar (GPR) data were acquired in the potash mine operated by the Joint Stock Company (JSC) "Silvinit" (Russia) as part of an investigation of both pre-existing fractures exposed by mine workings and other anomalous geological structures. During the course of GPR investigation, the electrical properties of salt-bearing units were determined, site-specific data acquisition techniques and object-oriented …


Inversion Of 2d And 3d Dc Resistivity Imaging Data Forhigh Contrast Geophysical Regions Using Artificial Neuralnetworks., Ahmad Neyamadpour Jan 2010

Inversion Of 2d And 3d Dc Resistivity Imaging Data Forhigh Contrast Geophysical Regions Using Artificial Neuralnetworks., Ahmad Neyamadpour

Student Works (2010-2019)

In electrical resistivity imaging surveys, the field data along a profile are normally acquired as a subsurface distribution of apparent resistivity. One common method to obtain the true resistivity distribution is by inverting the apparent resistivity values. However, the inversion of DC resistivity imaging data is complex due to its non-linearity. This is especially true for regions with high resistivity contrast. For the complicated subsurface structure, especially when regions of high resistivity contrast exist, a conventional inversion technique based on least squares methods may not be able to invert the DC resistivity data with adequate accuracy. Therefore, in this study, …


Hydrogeochemistry Of Caves Drip Water At Selected Caves In Peninsular Malaysia., Nor Bakhiah Baharim Jan 2010

Hydrogeochemistry Of Caves Drip Water At Selected Caves In Peninsular Malaysia., Nor Bakhiah Baharim

Student Works (2010-2019)

This preliminary study represents the study on hydrogeochemical of caves drip water throughout Peninsular Malaysia. All samples were analysed for pH, Total Dissolved Solid (TDS), Dissolved Oxygen (DO), Conductivity, cation and anion. Despite local hydrological and geological differences among sampling sites, the monitoring revealed significant synchronous intersite variations that related to rainfall variation and control the volume of water input. The constant hydraulic pressure is expected in karst system as a result of moist condition of tropical region and rainfall throughout the year. Drip sites were classified into to two classifications which are seepages flow and seasonal flow. A simplified …


Palinspastic Reconstruction Around A Thrust Belt Recess: An Example From The Appalachian Thrust Belt In Northwestern Georgia, Brian Stephen Cook Jan 2010

Palinspastic Reconstruction Around A Thrust Belt Recess: An Example From The Appalachian Thrust Belt In Northwestern Georgia, Brian Stephen Cook

University of Kentucky Doctoral Dissertations

In a well-defined subrecess in the Appalachian thrust belt in northwestern Georgia, two distinct regional strike directions intersect at approximately 50°. Fault intersections and interference folds enable tracing of both structural strikes. Around the subrecess, tectonically thickened weak stratigraphic layers—shales of the Cambrian Conasauga Formation—accommodated ductile deformation associated with the folding and faulting of the overlying Cambrian–Ordovician regional competent layer. The structures in the competent layer are analogous to those over ductile duplexes (mushwads) documented along strike to the southwest in Alabama.

The intersection and fold interference exemplify a long-standing problem in volume balancing of palinspastic reconstructions of sinuous thrust …


Effect Of Low And High- Kinetic Energy Wetting On Quality Of Sediment Produced By Interrill Erosion, Eduardo Abel Rienzi Jan 2010

Effect Of Low And High- Kinetic Energy Wetting On Quality Of Sediment Produced By Interrill Erosion, Eduardo Abel Rienzi

University of Kentucky Doctoral Dissertations

Raindrop kinetic energy and sheet flow can disintegrate aggregates during interrill erosion, a process responsible for non point source pollution. Also, the dissolution process during aggregate wetting can affect interrill erosion. These factors can be responsible for changes in particle size distribution in the sediment, especially when different tillage systems are compared. The effect of soil tillage and management on soil properties is not uniform, which determine a wide range of runoff and sediment delivery rate. Variety in these rates can be associated with pore functions and their interactions with aggregate stability. One of the objectives of this study was …


Characterization Of Soil Carbon Stabilization In Long-Term Row-Cropped Agro-Ecosystems, Soraya Patricia Alvarado-Ochoa Jan 2010

Characterization Of Soil Carbon Stabilization In Long-Term Row-Cropped Agro-Ecosystems, Soraya Patricia Alvarado-Ochoa

University of Kentucky Doctoral Dissertations

Soil organic matter (SOM) is a dynamic soil property, sensitive and responsive to many factors. The possibility of increasing soil carbon (C) sequestration by changing land use and management practices has been of great interest recently due to concerns with global changes in the atmospheric carbon dioxide (CO2) balance. Nonetheless, as a result of the complex dynamics of SOM, there is still the need for SOM characterization procedures capable of monitoring SOM stabilization, taking into account all the factors involved.

This study characterized SOM stabilization as affected by management practices in three long-term field experiments, considering physical, chemical …


Teaching Resources In Speleology And Karst: A Valuable Educational Tool, Jo De Waele Jan 2010

Teaching Resources In Speleology And Karst: A Valuable Educational Tool, Jo De Waele

International Journal of Speleology

There is a growing need in the speleological community of tools that make teaching of speleology and karst much easier. Despite the existence of a wide range of major academic textbooks, often the caver community has a difficult access to such material. Therefore, to fill this gap, the Italian Speleological Society, under the umbrella of the Union International de Spéléologie, has prepared a set of lectures, in a presentation format, on several topics including geology, physics, chemistry, hydrogeology, mineralogy, palaeontology, biology, microbiology, history, archaeology, artificial caves, documentation, etc. These lectures constitute the “Teaching Resources in Speleology and Karst”, available online. …


Uranium-Series Dating Of Gypsum Speleothems: Methodology And Examples, Laura Sanna, Francisco Saez, Siri Simonsen, Silviu Constantin, José-Maria Calaforra, Paolo Forti, Stein-Erik Lauritzen Jan 2010

Uranium-Series Dating Of Gypsum Speleothems: Methodology And Examples, Laura Sanna, Francisco Saez, Siri Simonsen, Silviu Constantin, José-Maria Calaforra, Paolo Forti, Stein-Erik Lauritzen

International Journal of Speleology

The analytical problems of dating gypsum speleothems with the U-series technique are reviewed. Gypsum speleothems are, in general, very low in U content, challenging the limits of detection methods. Various approaches to dissolving gypsum and isolation of actinides from the matrix include ion-pairing dissolution with magnesium salts and using nitric acid. The most precise dating technique is Thermal Ionization Mass Spectrometry (TIMS), combined with Fe(OH)3 scavenging and anionic exchange chromatography. Less satisfactory, but much quicker, is direct retention of actinides from HNO3 by means of TRU resin and MC-ICP-MS detection. We have tested these methods on gypsum speleothems …


Age Frequency Distribution And Revised Stable Isotope Curves For New Zealand Speleothems: Palaeoclimatic Implications, Paul W. Williams, Helen L. Neil, Jian-Xin Zhao Jan 2010

Age Frequency Distribution And Revised Stable Isotope Curves For New Zealand Speleothems: Palaeoclimatic Implications, Paul W. Williams, Helen L. Neil, Jian-Xin Zhao

International Journal of Speleology

The occurrence of speleothems in New Zealand with reversed magnetism indicates that secondary calcite deposition in caves has occurred for more than 780 thousand years (ka). 394 uranium-series dates on 148 speleothems show that such deposition has taken place somewhere in the country with little interruption for more than 500 ka. A relative probability distribution of speleothem ages indicates that most growth occurred in mild, moist interglacial and interstadial intervals, a conclusion reinforced by comparing peaks and troughs in the distribution with time series curves of speleothem δ18O and δ13C values. The stable isotope time series …


Temporal Controls On Dissolved Organic Matter And Lignin Biogeochemistry In A Pristine Tropical River, Democratic Republic Of Congo, Robert G. M. Spencer, Peter J. Hernes, Rosmarie Ruf, Andy Baker, Rachael Y. Dyda, Aron Stubbins, Johan Six Jan 2010

Temporal Controls On Dissolved Organic Matter And Lignin Biogeochemistry In A Pristine Tropical River, Democratic Republic Of Congo, Robert G. M. Spencer, Peter J. Hernes, Rosmarie Ruf, Andy Baker, Rachael Y. Dyda, Aron Stubbins, Johan Six

Chemistry & Biochemistry Faculty Publications

Dissolved organic carbon (DOC), lignin biomarkers, and the optical properties of dissolved organic matter (DOM) were measured in the Epulu River (northeast Democratic Republic of Congo) with the aim of investigating temporal controls on the quantity and chemical composition of DOM in a tropical rainforest river. Three different periods defined by stages of the hydrologic regime of the region, (1) post dry flushing period, (2) intermediary period, and (3) start of the dry period/post flush, were sampled. Temporal variability in DOM quantity and quality was observed with highest DOC, lignin concentration (Σ8) and carbon‐normalized (Λ8) values …


Land Surface Brightness Temperature Modeling Using Solar Insolation, Haroon Stephen, Sajjad Ahmad, Thomas C. Piechota Jan 2010

Land Surface Brightness Temperature Modeling Using Solar Insolation, Haroon Stephen, Sajjad Ahmad, Thomas C. Piechota

Public Policy and Leadership Faculty Research

Retrieval of land surface emissivity and temperature from microwave brightness temperature data is a complex problem. The diurnal variation of temperature due to the diurnal cycle of solar radiation and weather conditions makes this problem even more challenging. In this paper, we use solar radiation in modeling the temporal variation of the brightness temperature state of the surface. Solar insolation modeling is used to estimate the diurnal variation of land surface brightness temperature. Solar radiation and brightness temperature are linked through temperature of the surface which is derived based on the radiation balance equation. The temperature state model behaves consistent …


What Are The Causes, Consequences And Correctives Of Fish Contamination In The Detroit River Aoc That Cause Health Consumption Advisories? (Final Report, Michigan Sea Grant Michu-T-10-001), Donna R. Kashian, Ken G. Drouillard, D. Haffner, Ann E. Krause, Z Liu, Larissa Sano Jan 2010

What Are The Causes, Consequences And Correctives Of Fish Contamination In The Detroit River Aoc That Cause Health Consumption Advisories? (Final Report, Michigan Sea Grant Michu-T-10-001), Donna R. Kashian, Ken G. Drouillard, D. Haffner, Ann E. Krause, Z Liu, Larissa Sano

Environmental Science and Geology Faculty Research Publications

Using an Integrated Assessment (IA) framework, we consolidated and utilized existing data from the Detroit River to develop models that both identify possible drivers of elevated fish contaminant body burdens, and to facilitate a more risk-based approach of tissue trigger-levels for consumption advisories. This integrated assessment approach was particularly useful for consumption advisories as it provided the ability to integrate and organize complex data in a manner that can help inform management decisions. In addition, the IA framework explicitly fosters collaboration and participation of multiple interested groups. We have capitalized on this component of IAs, by seeking the active participation …


Concentrated Perchlorate At The Mars Phoenix Landing Site: Evidence For Thin Film Liquid Water On Mars, Selby Cull, Raymond E. Arvidson, Jeffrey G. Catalano, Douglas W. Ming, Richard V. Morris, Michael T. Mellon, Mark Lemmon Jan 2010

Concentrated Perchlorate At The Mars Phoenix Landing Site: Evidence For Thin Film Liquid Water On Mars, Selby Cull, Raymond E. Arvidson, Jeffrey G. Catalano, Douglas W. Ming, Richard V. Morris, Michael T. Mellon, Mark Lemmon

Geology Faculty Research and Scholarship

NASA's Phoenix mission, which landed on the northern plains of Mars in 2008, returned evidence of the perchlorate anion distributed evenly throughout the soil column at the landing site. Here, we use spectral data from Phoenix's Surface Stereo Imager to map the distribution of perchlorate salts at the Phoenix landing site, and find that perchlorate salt has been locally concentrated into subsurface patches, similar to salt patches that result from aqueous dissolution and redistribution on Earth. We propose that thin films of liquid water are responsible for translocating perchlorate from the surface to the subsurface, and for concentrating it in …


Age And Structure Of The San Jacinto And San Felipe Fault Zones And Their Lifetime Slip Rates, Susanne U. Janecke, R. J. Dorsey, B. Belgarde Jan 2010

Age And Structure Of The San Jacinto And San Felipe Fault Zones And Their Lifetime Slip Rates, Susanne U. Janecke, R. J. Dorsey, B. Belgarde

Geosciences Faculty Publications

No abstract provided.


Basement Types, Lower Eocene Series, Upper Eocene Olistostromes And The Initiation Of The Southern Thrace Basin, Nw Turkey, Aral İ. Okay, Ercan Özcan, William Cavazza, Ni̇lgün Okay, György Less Jan 2010

Basement Types, Lower Eocene Series, Upper Eocene Olistostromes And The Initiation Of The Southern Thrace Basin, Nw Turkey, Aral İ. Okay, Ercan Özcan, William Cavazza, Ni̇lgün Okay, György Less

Turkish Journal of Earth Sciences

The Eocene sequence of the southern Thrace Basin unconformably overlies two types of basement: (1) Slate, limestone and phyllite crop out in small inliers under the Upper Eocene conglomerates and limestones in the Mecidiye region, north of Saros Bay. These low-grade metamorphic rocks form the eastern extension of the Circum-Rhodope Belt of Greece. (2) In the Şarköy region south of the Ganos Fault, tectonically elevated basement consisting of serpentinite, metadiabase and Upper Cretaceous blueschists is unconformably overlain by the upper Bartonian to lower Priabonian shallow marine limestones of the Soğucak Formation. In some places erosional remnants of an upper Ypresian …


Stratigraphy And Larger Foraminifera Of The Eocene Shallow-Marine And Olistostromal Units Of The Southern Part Of The Thrace Basin, Nw Turkey, Ercan Özcan, György Less, Aral İ. Okay, Mária Báldi-Beke, Katalin Kollányi, İsmai̇l Ömer Yilmaz Jan 2010

Stratigraphy And Larger Foraminifera Of The Eocene Shallow-Marine And Olistostromal Units Of The Southern Part Of The Thrace Basin, Nw Turkey, Ercan Özcan, György Less, Aral İ. Okay, Mária Báldi-Beke, Katalin Kollányi, İsmai̇l Ömer Yilmaz

Turkish Journal of Earth Sciences

The Eocene marine sequence in the southern part of the Thrace Basin (NW Turkey) involves a variety of platform and deep-marine olistostromal units, the stratigraphy of which have been vigorously debated in the past. A detailed analysis of larger foraminifera in these either foraminifera or foraminifera-coral-coralline algae-dominated platform and associated comparatively deeper-marine units permits us to establish a high-resolution biostratigraphy in the context of shallow benthic zonation (with SBZ zones) of Tethyan Paleogene. The oldest zone (SBZ 5, corresponding to the basal Ypresian) was observed only in olistoliths. An old erosional remnant of a transgressive shallow-marine to basinal sequence (Dişbudak …


Surface And Subsurface Characteristics Of The Çankırı Basin (Central Anatolia, Turkey): Integration Of Remote Sensing, Seismic Interpretation And Gravity, Nuretdi̇n Kaymakçi, Şenol Özmutlu, Paul M. Van Van Dijk, Yakup Özçeli̇k Jan 2010

Surface And Subsurface Characteristics Of The Çankırı Basin (Central Anatolia, Turkey): Integration Of Remote Sensing, Seismic Interpretation And Gravity, Nuretdi̇n Kaymakçi, Şenol Özmutlu, Paul M. Van Van Dijk, Yakup Özçeli̇k

Turkish Journal of Earth Sciences

The geology of the Çankırı Basin has been studied using multi-source data including satellite images, aerial photos, gravimetric data and seismic sections, which are subsequently used to generate maps and a 3D model of that part of the basin covered by the seismic sections. From the compilation, three different phases of deformation are recognized. The earliest phase is characterized by thrusting during the Early Tertiary. The second deformation phase is characterized by extensional deformation associated with normal faulting in the latest Early Miocene to Middle Miocene. The third, and the last, phase is characterized by compressional deformation manifested by inversion …


Volcanic Rocks From Foça-Karaburun And Ayvalik-Lesvos Grabens (Western Anatolia) And Their Petrogenetic-Geodynamic Significance, Samuele Agostini, Murat Tokçaer, Mehmet Yilmaz Savaşçin Jan 2010

Volcanic Rocks From Foça-Karaburun And Ayvalik-Lesvos Grabens (Western Anatolia) And Their Petrogenetic-Geodynamic Significance, Samuele Agostini, Murat Tokçaer, Mehmet Yilmaz Savaşçin

Turkish Journal of Earth Sciences

The Foça-Karaburun and Ayvalık-Lesvos grabens (western coast of Anatolia, Turkey) are two important NW-SE-trending extensional areas generated in response to the Early Miocene-Holocene extension of the Western Anatolian region, related to the opening of the "unconventional" back-arc basin of the Aegean Sea. The abundance of geo-structural evidence and the occurrence of volcanic rocks representing all the stages of the Aegean-Western Anatolia volcanism render the Foça-Karaburun and Ayvalık-Lesvos Grabens key localities to exemplify the petrogenetic and geodynamic evolution of the area. In this context, the Foça-Karaburun and Ayvalık-Lesvos grabens, possibly formerly a single graben, formed along an original NE-SW-trending extension, later …


Foraminiferal Biostratigraphy And Palaeoenvironmental Reconstruction Of The Paleocene–Eocene Transition At The Kharrouba Section, Tunisia (Southern Tethys Margin), Lamia Zili, Dalila Zaghbib-Turki Jan 2010

Foraminiferal Biostratigraphy And Palaeoenvironmental Reconstruction Of The Paleocene–Eocene Transition At The Kharrouba Section, Tunisia (Southern Tethys Margin), Lamia Zili, Dalila Zaghbib-Turki

Turkish Journal of Earth Sciences

At Kharrouba (near Tunis City in northern Tunisia), on the southern margin of the Tethyan realm, the Paleocene-Eocene (P-E) transition interval deposition is continuous and complete. Based on high-resolution analysis and quantitative data of planktonic and benthic foraminifera at the Kharrouba section, this transition interval records expanded deposition of the relevant standard planktonic foraminiferal biozones with indicative index species i.e.: Morozovella velascoensis for the latest Paleocene P5 zone, and Acarinina sibaiyaensis for the earliest Eocene E1 zone, Pseudohastigerina wilcoxensis for the E2 zone, Morozovella marginodentata for the E3 zone and Morozovella formosa for the E4 zone. This complete section contains …


Danielita Gailloti N.Gen., N. Sp., Within The Evolutionary Framework Of Middle-Late Permian Dagmaritins, Demi̇r Altiner, Sevi̇nç Özkan Altiner Jan 2010

Danielita Gailloti N.Gen., N. Sp., Within The Evolutionary Framework Of Middle-Late Permian Dagmaritins, Demi̇r Altiner, Sevi̇nç Özkan Altiner

Turkish Journal of Earth Sciences

The name Danielita is proposed for a new dagmaritin genus characterized by a biserial arrangement of chambers with spine-like extensions at chamber corners and a perforated wall. Danielita differs from Dagmarita, from which it was derived, by a perforated wall and constitutes one of the peculiar evolutionary trends of the dagmaritin stock. Early dagmaritins evolved from Globivalvulina cyprica by the appearance of Sengoerina in the Capitanian and the frequently encountered association G. cyprica-Sengoerina-Dagmarita-Danielita in Turkey suggests that the evolutionary derivations of dagmaritin genera occurred very rapidly in the Capitanian. The subfamily Paradagmaritinae is synonymized under the subfamily Dagmaritinae. Among recently …


Application Of The Normalized Full Gradient (Nfg) Method To Resistivity Data, Ali̇ Aydin Jan 2010

Application Of The Normalized Full Gradient (Nfg) Method To Resistivity Data, Ali̇ Aydin

Turkish Journal of Earth Sciences

This paper proposes the application of the normalized full gradient (NFG) method to resistivity studies and illustrates that the method can greatly reduce the time and work load needed in detecting buried bodies using resistivity measurement. The NFG method calculates resistivity values at desired electrode offsets by extrapolation of a function of resistivity measurements (i.e. the gradient) to other depth levels using resistivity measurements done at one electrode offset only. The performance and reliability of the NFG method is tested on laboratory and field resistivity data from two sites by comparing the trend of the resistivity values at six or …


Ontogeny And Funtional Morphology Of A Lower Cretaceous Carpinid Rudist (Bivalvia, Hippuritoida), Robert W. Scott, Meghan Weaver Jan 2010

Ontogeny And Funtional Morphology Of A Lower Cretaceous Carpinid Rudist (Bivalvia, Hippuritoida), Robert W. Scott, Meghan Weaver

Turkish Journal of Earth Sciences

Caprinuloidea rudists are locally abundant and widespread in Lower Cretaceous (Albian Stage) Edwards Formation in Texas. Landward of the shelf margin on the shallow marine Comanche Shelf rudists built circular and elongate bioherms with coarse-grained flank deposits. Two caprinid morphotypes suggest that some lived as elevators above the substrate and others were recumbent upon mobile grain flats. Elevators have elongated attached valves and weakly coiled free valves and recumbents have arcuate attached valves and strongly coiled free valves. Detailed morphologic studies are not possible on the many molds and casts, but a few specimens are silicified. Their internal structures can …


A New Species Of Polyconites From The Lower Aptian Of Iberia And The Early Evolution Of Polyconitid Rudists, Peter W. Skelton, Eulàlia Gili, Telm Bover-Arnal, Ramon Salas, Josep Anton Moreno-Bedmar Jan 2010

A New Species Of Polyconites From The Lower Aptian Of Iberia And The Early Evolution Of Polyconitid Rudists, Peter W. Skelton, Eulàlia Gili, Telm Bover-Arnal, Ramon Salas, Josep Anton Moreno-Bedmar

Turkish Journal of Earth Sciences

The main diagnostic character of polyconitid rudists is a distinctive ectomyophoral cavity inserted behind a reflexed posterior myophoral plate in the left valve. The only pre-Aptian Old World polyconitid taxon recognized in the current literature is Horiopleura dumortieri (Matheron): this species clearly shows the prominent posterior myophoral shelf in the right valve that is diagnostic of the genus, which continues into the Albian. Polyconites, by contrast, has a more depressed (operculiform) left valve and its posterior adductor was inserted on an inward-sloping swelling on the right valve inner wall, with no projecting shelf. Hitherto, the earliest known species of Polyconites …


Dictyoptychus Douvillé: Taxonomic Revision, Phylogeny And Biogeography, Saci̇t Özer Jan 2010

Dictyoptychus Douvillé: Taxonomic Revision, Phylogeny And Biogeography, Saci̇t Özer

Turkish Journal of Earth Sciences

The late Campanian-Maastrichtian transgressive sequences of the southeastern Anatolia (northernmost part of the Arabian platform) and only one Maastrichtian limestone block within the ophiolitic association of the easternmost part of the Taurus Orogenic Belt contain very well-preserved specimens of Dictyoptychus Douvillé 1905. Study of Turkish specimens and also of those described in the literature reveals considerable ontogenic variability, hence need for revision of the species of the genus erected hitherto. Dictyoptychus leesi (Kühn 1929), Dictyoptychus paronai (Kühn 1929), Dictyoptychus persicus (Cox 1934), Dictyoptychus euphratica Karacabey-Öztemür 1979 and Dictyoptychus orontica Karacabey-Öztemür 1979 are accordingly re-interpreted to represent a single species synonymous …


Late Campanian Rudist Assemblages And Biometrical Analysis Of Pseudopolyconites From Bačevica (Eastern Serbia), Tunis Giorgio, Tarlao Alceo, Radoicic Rajka Jan 2010

Late Campanian Rudist Assemblages And Biometrical Analysis Of Pseudopolyconites From Bačevica (Eastern Serbia), Tunis Giorgio, Tarlao Alceo, Radoicic Rajka

Turkish Journal of Earth Sciences

The lithological and faunal succession cropping out close to the famous palaeontological locality of Bacevica (Eastern Serbia) is described along a very discontinuous and ill-exposed section. Since the section is dominated by clastic sediments, no-vestige of the so-called 'Vrbovac reef' has been observed. Rhythms consisting of a limestone breccia lower unit and a fossil-rich upper part characterize the base of the section while rare silt and sand-rich limestone breccias and prevailing silty/sandy soils are the lithologies observed in the upper part of the same. The faunal succession shows an alternation of monospecific-paucispecific assemblages and much more diverse assemblages of rudists. …