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Differences In Antibiotic Resistance In Fresh-Water Bacteria From Furman Lake And Feeder Streams, Dylan Richards, Clarissa Graham, Laura Snyder Jan 2010

Differences In Antibiotic Resistance In Fresh-Water Bacteria From Furman Lake And Feeder Streams, Dylan Richards, Clarissa Graham, Laura Snyder

Furman Lake Restoration Book Gallery

A one page summary by three Furman students describing their research on bacteria found in the Furman Lake.


The Effect Of Bioretention Areas On The Heavy Ion Concentration, Ph, And Water Quality Of The Furman University Lake, Adam Williams, Ashley Brown, Matthew Stutz Jan 2010

The Effect Of Bioretention Areas On The Heavy Ion Concentration, Ph, And Water Quality Of The Furman University Lake, Adam Williams, Ashley Brown, Matthew Stutz

Furman Lake Restoration Book Gallery

A one page summary by four Furman students describing their research on the effectiveness of the bioretention areas, or rain gardens, created as part of the Lake Restoration Project.


The Distribution Of Macroalgae In Furman Lake, Anthony Guida, Jeff Hennessy, Meredith Yingling, Vanessa Argüello Jan 2010

The Distribution Of Macroalgae In Furman Lake, Anthony Guida, Jeff Hennessy, Meredith Yingling, Vanessa Argüello

Furman Lake Restoration Book Gallery

A three page summary by four Furman students describing their research on macroalge in the Furman Lake. The goal is to test whether or not the restoration efforts have significantly changed the algae cover in the lake.


The Effect Of The Lake Restoration Project On Passerine Bird Diversity, Gina Tong, Brittany Martin, Stephanie Field, Whitney Snow, Whitney Millegan, Chris Cowart Jan 2010

The Effect Of The Lake Restoration Project On Passerine Bird Diversity, Gina Tong, Brittany Martin, Stephanie Field, Whitney Snow, Whitney Millegan, Chris Cowart

Furman Lake Restoration Book Gallery

A three page summary by six Furman students showing their research results on the lake restoration's effects on passerine bird populations.


The Effect Of The Lake Restoration Project On Habitat Use By Waterfowl, Denae Buzzell, Clay Evans, Hannah Shirley, Lin Lin Zhao Jan 2010

The Effect Of The Lake Restoration Project On Habitat Use By Waterfowl, Denae Buzzell, Clay Evans, Hannah Shirley, Lin Lin Zhao

Furman Lake Restoration Book Gallery

A two page summary by four Furman students describing their research on waterfowl around the Furman Lake. The summary gives a brief history waterfowl populations and explains the adverse effects of large waterfowl populations on calm bodies of water. The summary concludes with test results showing the success of the lake restoration efforts dealing with waterfowl overpopulation.


Climatic And Environmental Controls On The Occurrence And Distributions Of Long Chain Alkenones In Lakes Of The Interior United States, Jaime L. Toney, Yongsong Huang, Sherilyn C. Fritz, Paul A. Baker, Eric Grimm, Paul Nyren Jan 2010

Climatic And Environmental Controls On The Occurrence And Distributions Of Long Chain Alkenones In Lakes Of The Interior United States, Jaime L. Toney, Yongsong Huang, Sherilyn C. Fritz, Paul A. Baker, Eric Grimm, Paul Nyren

Department of Earth and Atmospheric Sciences: Faculty Publications

Long chain alkenones (LCA) are temperature-sensitive lipids with great potential for quantitative reconstruction of past continental climate. We conducted the first survey for alkenone biomarkers from 55 different lakes in the Northern Great Plains and Nebraska Sand Hills of the United States. Among those surveyed, we found 13 lakes that contain LCAs in the surface sediments. The highest concentrations of alkenones in sediments are found in cold (mean annual air temperature ~11 °C versus 17 °C in our warmest sites), brackish to mesosaline (salinity = 8.5–9.7 g/L), and alkaline (pH = 8.4–9.0) lakes with high concentrations of sodium and sulfate. …


An Evaluation Of Lead Concentrations In Surface Soils And Sediments Within Lytle Creek Drainage Basin, Harvey Clark Norton Jan 2010

An Evaluation Of Lead Concentrations In Surface Soils And Sediments Within Lytle Creek Drainage Basin, Harvey Clark Norton

Theses Digitization Project

This paper represents a master's project that is a preliminary surface soil survey of the Lytle Creek sub-Watershed, near Devore, California. The sub-Watershed is a recreational site within the San Bernardino National Forest. This study was undertaken to determine the concentration of lead and lead salts within the soils and sediments within the watershed, and to determine if these products pose a threat to the health of the local environment and human consumers from the watershed. Possible sources of lead contamination include natural background geology, contamination of historical use of gasoline with lead additives, and the presence of outdoor shooting …


Effects Of Drought On Avian Community Structure, Thomas P. Albright, Anna M. Pidgeon, Chadwick D. Rittenhouse, Murray K. Clayton, Curtis H. Flather, Patrick D. Culbert, Brian D. Wardlows, Volker C. Radeloff Jan 2010

Effects Of Drought On Avian Community Structure, Thomas P. Albright, Anna M. Pidgeon, Chadwick D. Rittenhouse, Murray K. Clayton, Curtis H. Flather, Patrick D. Culbert, Brian D. Wardlows, Volker C. Radeloff

National Drought Mitigation Center: Faculty Publications

Droughts are expected to become more frequent under global climate change. Avifauna depend on precipitation for hydration, cover, and food. While there are indications that avian communities respond negatively to drought, little is known about the response of birds with differing functional and behavioral traits, what time periods and indicators of drought are most relevant, or how response varies geographically at broad spatial scales. Our goals were thus to determine (1) how avian abundance and species richness are related to drought, (2) whether community variations are more related to vegetation vigor or precipitation deviations and at what time periods relationships …


An Inventory And Condition Survey Of The Western Australian Part Of The Nullarbor Region, Peter-Jon A. Waddell, A K. Gardner, P Hennig Jan 2010

An Inventory And Condition Survey Of The Western Australian Part Of The Nullarbor Region, Peter-Jon A. Waddell, A K. Gardner, P Hennig

Technical Bulletins

The inventory and condition survey of the Western Australian part of the Nullarbor region, undertaken by the Department of Agriculture and Food, Western Australia (DAFWA) between 2005 and 2007, describes and maps the natural resources of the region. This survey report provides a baseline record of the existence and condition of the area's natural resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The Nullarbor region has …


Forest Analysis Of The Gordon Natural Area Focusing On Carbon Stock, Forest Structure, And Forest Composition, R. Dicce, D. Drake, D. Mackey, P. Avery Jan 2010

Forest Analysis Of The Gordon Natural Area Focusing On Carbon Stock, Forest Structure, And Forest Composition, R. Dicce, D. Drake, D. Mackey, P. Avery

Forest Carbon Storage Study Documents

No abstract provided.


Temporal And Spatial Variations In Freshwater 14C Reservoir Effects: Lake Mývatn, Northern Iceland, Philippa L. Ascough, G. T. Cook, M. J. Church, E. Dunbar, Á. Einarsson, Thomas H. Mcgovern, A. J. Dugmore, Sophia Perdikaris, H. Hastie, A. Friðriksson, H. Gestsdóttir Jan 2010

Temporal And Spatial Variations In Freshwater 14C Reservoir Effects: Lake Mývatn, Northern Iceland, Philippa L. Ascough, G. T. Cook, M. J. Church, E. Dunbar, Á. Einarsson, Thomas H. Mcgovern, A. J. Dugmore, Sophia Perdikaris, H. Hastie, A. Friðriksson, H. Gestsdóttir

School of Global Integrative Studies: Faculty Publications

Lake Mývatn is an interior highland lake in northern Iceland that forms a unique ecosystem of international scientific importance and is surrounded by a landscape rich in archaeological and paleoenvironmental sites. A significant freshwater reservoir effect (FRE) has been identified in carbon from the lake at some Viking (about AD 870–1000) archaeological sites in the wider region (Mývatnssveit). Previous accelerator mass spectrometry (AMS) measurements indicated this FRE was about 1500–1900 14C yr. Here, we present the results of a study using stable isotope and 14C measurements to quantify the Mývatn FRE for both the Viking and modern periods. …


The Influence Of Nutrients And Physical Habitat In Regulating Algal Biomass In Agricultural Streams, Mark D. Munn, Jeffrey Frey, Anthony Tesoriero Jan 2010

The Influence Of Nutrients And Physical Habitat In Regulating Algal Biomass In Agricultural Streams, Mark D. Munn, Jeffrey Frey, Anthony Tesoriero

United States Geological Survey: Water Reports and Publications

This study examined the relative influence of nutrients (nitrogen and phosphorus) and habitat on algal biomass in five agricultural regions of the United States. Sites were selected to capture a range of nutrient conditions, with 136 sites distributed over five study areas. Samples were collected in either 2003 or 2004, and analyzed for nutrients (nitrogen and phosphorous) and algal biomass (chlorophyll a). Chlorophyll a was measured in three types of samples, fine-grained benthic material (CHLFG), coarse-grained stable substrate as in rock or wood (CHLCG), and water column (CHLS). Stream and riparian habitat were characterized at each site. TP ranged from …


Mercury Concentrations In Fish From A Sierra Nevada Foothill Reservoir Located Downstream From Historic Gold-Mining Operations, Michael K. Saiki, Barbara A. Martin, Thomas W. May, Charles N. Alpers Jan 2010

Mercury Concentrations In Fish From A Sierra Nevada Foothill Reservoir Located Downstream From Historic Gold-Mining Operations, Michael K. Saiki, Barbara A. Martin, Thomas W. May, Charles N. Alpers

United States Geological Survey: Staff Publications

This study examined mercury concentrations in whole fish from Camp Far West Reservoir, an 830-ha reservoir in northern California, USA, located downstream from lands mined for gold during and following the Gold Rush of 1848–1864. Total mercury (reported as dry weight concentrations) was highest in spotted bass (mean, 0.93 μg/g; range, 0.16–4.41 μg/g) and lower in bluegill (mean, 0.45 μg/g; range, 0.22– 1.96 μg/g) and threadfin shad (0.44 μg/g; range, 0.21–1.34 μg/g). Spatial patterns for mercury in fish indicated high concentrations upstream in the Bear River arm and generally lower concentrations elsewhere, including downstream near the dam. These findings coincided …


Droughtscape, Winter 2010, Kelly Smith Jan 2010

Droughtscape, Winter 2010, Kelly Smith

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

USDM Forum Highlights

Drought Likely to Ease

Research Shows Birds Vulnerable to Drought

Drought Recedes in 2009

CA, TX Suffer Impacts from Ongoing Drought

NDMC Wishes Ryu Well

Conferees Pick SPI for Global Drought Index


Landscapes And Soils Of The Northam District, D N. Sawkins, Department Of Agriculture And Food Jan 2010

Landscapes And Soils Of The Northam District, D N. Sawkins, Department Of Agriculture And Food

Bulletins 4000 -

The publication aims to provide readers with the principles underlying the formation of local landscapes and soils, and the ability to identify landscapes and their associated soils.


Salinity Dynamics Of Discharge Lakes In Dune Environments: Conceptual Model, Vitaly A. Zlotnik, Neville I. Robinson, Craig T. Simmons Jan 2010

Salinity Dynamics Of Discharge Lakes In Dune Environments: Conceptual Model, Vitaly A. Zlotnik, Neville I. Robinson, Craig T. Simmons

Department of Earth and Atmospheric Sciences: Faculty Publications

Lakes of varying salinity are ubiquitous in dune environments with semiarid climates. Often these lakes become solute traps due to specific groundwater flow conditions. Over geological time after emergence of such lakes, the groundwater flow and mass transport processes lead to accumulation of solutes. This salinity increase can result in mineral deposition and free convection from lakes. However, high solute concentrations in these lakes are often not observed. We propose a conceptual model that estimates the lake salinity dynamics and yields concentration profiles beneath the lakes over centennial and millennial scales. Unlike previous approaches, a simple mathematical model is proposed …


Landscapes And Soils Of The Narrogin District, D N. Sawkins Jan 2010

Landscapes And Soils Of The Narrogin District, D N. Sawkins

Bulletins 4000 -

The publication aims to provide readers with the principles underlying the formation of local landscapes and soils, and the ability to identify landscapes and their associated soils.


The Effect Of Soil Regimes And Topography On Tree Community Composition In The Gordon Natural Area, Calen Daugherty, William Hochella, Kyle Houser, Sarah Johnson, Carolyn Keene Jan 2010

The Effect Of Soil Regimes And Topography On Tree Community Composition In The Gordon Natural Area, Calen Daugherty, William Hochella, Kyle Houser, Sarah Johnson, Carolyn Keene

Gordon Natural Area Soils Studies Documents

No abstract provided.


Microfacies Analysis Of The Jacksboro Limestone Member (Graham Formation, Virgilian, Pennsylvanian) In Jack County, Texas, Claudio Manuel Leyva Jan 2010

Microfacies Analysis Of The Jacksboro Limestone Member (Graham Formation, Virgilian, Pennsylvanian) In Jack County, Texas, Claudio Manuel Leyva

Earth & Environmental Sciences Theses - Archive

The Jacksboro Limestone is a member of the Graham Formation of the Virgilian (Upper Pennsylvanian) and is exposed only in and around the city of Jacksboro in central Jack County, Texas. The purposes of this investigation were to study the vertical and lateral microfacies changes that occur throughout the Jacksboro Limestone in its outcrop belt and to discuss its relationship as the basal regressive cycle in the Virgilian part of the Pennsylvanian, in particular: (1) describe and classify the primary limestone lithofacies on the basis of carbonate rock textures, (2) interpret, if possible, the depositional environment and physical energy of …


Enigmatic Structures On Upper Pleistocene Laminar Caliche Surfaces Of The Bahamas: Animal, Vegetable, Or Mineral?, H. Allen Curran Jan 2010

Enigmatic Structures On Upper Pleistocene Laminar Caliche Surfaces Of The Bahamas: Animal, Vegetable, Or Mineral?, H. Allen Curran

Geosciences: Faculty Publications

Trace fossils are a common and important component of most Quaternary carbonate rock units of the Bahamas and other, similar tropical carbonate regions. In the Bahamas, the Pleistocene-Holocene boundary is typically marked by a calichified paleosol horizon that formed on the exposed limestone surfaces of the islands during the time of lowered sea level of the Last Glacial. On the north coast of San Salvador Island, an extensive horizontal surface of laminar caliche is exposed at Singer Bar Point and to the west. This surface formed on carbonate eolianite of Late Pleistocene (Eemian) age and is overlain by Holocene eolianite. …


Albian Rudist Fauna From The Karaburun Peninsula, İzmir Region, Western Turkey, Jean-Pierre Masse, Mükerrem Fenerci̇-Masse, İsmai̇l Işintek, Tali̇p Güngör Jan 2010

Albian Rudist Fauna From The Karaburun Peninsula, İzmir Region, Western Turkey, Jean-Pierre Masse, Mükerrem Fenerci̇-Masse, İsmai̇l Işintek, Tali̇p Güngör

Turkish Journal of Earth Sciences

Platform carbonates bearing shallow water foraminifera and dasycladale assemblages with an Albian stratigraphic significance, crop out at two localities on the Karaburun Peninsula: Barbaros and Zeytineli. Rudist faunas collected from these localities include Toucasia seunesi Douvillé, Pseudotoucasia catalaunica Astre , Mathesia darderi (Astre), Petalodontia ? sp., and Eoradiolites sp. aff. murgensis. The overall stratigraphic significance of this fauna is consistent with the Albian age derived from micropalaeontological data. Some taxonomic elements, e.g. Toucasia seunesi, Pseudotoucasia catalaunica and Mathesia darderi possess a broad Mediterranean palaeobiogeographic distribution. By contrast, Eoradiolites sp. aff. murgensis, an advanced form resembling Eoradiolites murgensis, restricted to the …


Epidiceras (Bivalvia, Hippuritoidea) From The Tithonian–Berriasian Torinosu-Type Limestones Of The Sakawa Area, Southwest Japan, Shin-Ichi Sano, Peter W. Skelton Jan 2010

Epidiceras (Bivalvia, Hippuritoidea) From The Tithonian–Berriasian Torinosu-Type Limestones Of The Sakawa Area, Southwest Japan, Shin-Ichi Sano, Peter W. Skelton

Turkish Journal of Earth Sciences

Excavated specimens of two primitive rudists, Epidiceras speciosum (Goldfuss) and Epidiceras guirandi (de Loriol), are systematically described for the first time from the Tithonian-Berriasian Torinosu-type limestones of the Torinosu Group in the Sakawa area, Central Shikoku, Southwest Japan. E. guirandi was previously known only from the Late Kimmeridgian Mediterranean Tethys, so this occurrence in Southwest Japan significantly extends the recorded biogeographical and stratigraphical distribution of the species. Moreover, the documentation of E. speciosum from the Torinosu-type limestones in Japan and the Bau Limestone in Sarawak, Borneo, indicate that this species was already widespread throughout the Tethyan Realm at that time. …


Benthic Ecology From Space: Optics And Net Primary Production In Seagrass And Benthic Algae Across The Great Bahama Bank, Heidi M. Dierssen, Richard C. Zimmerman, Lisa A. Drake, David J. Burdige Jan 2010

Benthic Ecology From Space: Optics And Net Primary Production In Seagrass And Benthic Algae Across The Great Bahama Bank, Heidi M. Dierssen, Richard C. Zimmerman, Lisa A. Drake, David J. Burdige

OES Faculty Publications

Development of repeatable and quantitative tools are necessary for determining the abundance and distribution of different types of benthic habitats, detecting changes to these ecosystems, and determining their role in the global carbon cycle. Here we used ocean color remote sensing techniques to map different major groups of primary producers and estimate net primary productivity (NPP) across Great Bahama Bank (GBB). Field investigations on the northern portion of the GBB in 2004 revealed 3 dominant types of benthic primary producers: seagrass, benthic macroalgae, and microalgae attached to sediment. Laboratory measurements of NPP ranged from barely net autotrophic for grapestone sediment …


On The Fractional Solubillity Of Copper In Marine Aerosols: Toxicity Of Aeolian Copper Revisited, Edward R. Sholkovitz, Peter N. Sedwick, Thomas M. Church Jan 2010

On The Fractional Solubillity Of Copper In Marine Aerosols: Toxicity Of Aeolian Copper Revisited, Edward R. Sholkovitz, Peter N. Sedwick, Thomas M. Church

OES Faculty Publications

Paytan et al. (2009) argue that the atmospheric deposition of aerosols lead to copper concentrations that are potentially toxic to marine phytoplankton in a large area of tropical and subtropical North Atlantic Ocean. A key assumption in their model is that all marine aerosols (mineral dust and anthropogenic particles) have a high (40%) fractional solubility of copper. Our data show that the fractional solubility of copper for Saharan dust over the Sargasso Sea and Bermuda is significantly lower (1-7%). In contrast, anthropogenic aerosols with non-Saharan sources have significantly higher values (10-100%). Hence, the potential Cu toxicity in the tropical and …


A Seasonal Study Of Dissolved Cobalt In The Ross Sea, Antarctica: Micronutrient Behavior, Absence Of Scavenging, And Relationships With Zd, Cd, And P., M. A. Saito, T. J. Goepfert, A. E. Noble, E. M. Bertrand, Peter N. Sedwick, Giacomo R. Ditullio Jan 2010

A Seasonal Study Of Dissolved Cobalt In The Ross Sea, Antarctica: Micronutrient Behavior, Absence Of Scavenging, And Relationships With Zd, Cd, And P., M. A. Saito, T. J. Goepfert, A. E. Noble, E. M. Bertrand, Peter N. Sedwick, Giacomo R. Ditullio

OES Faculty Publications

We report the distribution of cobalt (Co) in the Ross Sea polynya during austral summer 2005-2006 and the following austral spring 2006. The vertical distribution of total dissolved Co (dCo) was similar to soluble reactive phosphate (PO(4)(3-)), with dCo and PO(4)(3-) showing a significant correlation throughout the water column (r(2) = 0.87, 164 samples). A strong seasonal signal for dCo was observed, with most spring samples having concentrations ranging from similar to ~ 45-85 pM, whereas summer dCo values were depleted below these levels by biological activity. Surface transect data from the summer cruise revealed concentrations at the low range …


Variations In Synechococcus Cell Quotas Of Phosphorus, Sulfur, Manganese, Iron, Nickel, And Zinc Within Mesoscale Eddies In The Sargasso Sea, Benjamin S. Twining, Daliangelis Nunez-Milland, Stefan Vogt, Rodney S. Johnson, Peter N. Sedwick Jan 2010

Variations In Synechococcus Cell Quotas Of Phosphorus, Sulfur, Manganese, Iron, Nickel, And Zinc Within Mesoscale Eddies In The Sargasso Sea, Benjamin S. Twining, Daliangelis Nunez-Milland, Stefan Vogt, Rodney S. Johnson, Peter N. Sedwick

OES Faculty Publications

The quotas of P, S, Mn, Fe, Ni, and Zn in individual Synechococcus cells collected from the surface and deep chlorophyll maximum (DCM) layer of three mesoscale eddies in the Sargasso Sea were measured using synchrotron X-ray fluorescence microscopy. Cells in a mode-water eddy had significantly higher P (57 +/- 10 amol) and Mn (28 +/- 7 zmol) cell quotas than cells collected from a cyclone (22 +/- 2 amol and 10 +/- 1 zmol, respectively) or anticyclone (25 +/- 3 amol and 18 +/- 3 zmol, respectively). Conversely, Ni and Zn quotas were significantly higher in the cells from …


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 …


Plant Isotopes As Indicators Of N Cycling Processes In Agricultural Fields, Eric Thuss Jan 2010

Plant Isotopes As Indicators Of N Cycling Processes In Agricultural Fields, Eric Thuss

Theses and Dissertations (Comprehensive)

When nitrogen (N) availability exceeds biological demand, excess N, especially nitrate (NO3), may subsequently pollute ground and surface water. Agricultural practices in Southern Ontario typically supplement soils with organic and inorganic nutrients to aid in crop development, and employ various management techniques to limit nutrient loss. Excess N has several potential fates, which are controlled by the net effects of numerous N cycling reactions in the soil that are often difficult to measure directly. N cycling in soils is controlled in large part by soil moisture, as it affects microbial activity and soil redox conditions. Stable isotope geochemistry …


Carbon Dioxide Exchange In A Permafrost-Dominated Boreal Wetland In The Northwest Territories, Canada, Andrea J. Kenward Jan 2010

Carbon Dioxide Exchange In A Permafrost-Dominated Boreal Wetland In The Northwest Territories, Canada, Andrea J. Kenward

Theses and Dissertations (Comprehensive)

Northern boreal wetland complexes are substantial reservoirs for carbon and play a crucial role in both regional and global carbon budgets but they are showing significant signs of impact by climate change. This study examined the carbon dioxide flux of a high boreal wetland during the snowmelt and growing season of 2008 in Scotty Creek Basin, located near Fort Simpson (61°18'N, 121°18'W), Northwest Territories. This basin is not only responding to shifts in atmospheric temperatures, but it is also under additional pressure from increasing permafrost degradation. A dynamic closed-system chamber was used to monitor and quantify mid-day total respiration (R …


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 …