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An Extraordinary Example Of Photokarren In A Sandstone Cave, Cueva Charles Brewer, Chimantá Plateau, Venezuela: Biogeomorphology On A Small Scale, Joyce Lundberg, Donald A. Mcfarlane, Charles Brewer-Carias Jan 2010

An Extraordinary Example Of Photokarren In A Sandstone Cave, Cueva Charles Brewer, Chimantá Plateau, Venezuela: Biogeomorphology On A Small Scale, Joyce Lundberg, Donald A. Mcfarlane, Charles Brewer-Carias

WM Keck Science Faculty Papers

A distinctive suite of small-scale erosional forms that are oriented towards the light occur close to the entrance of Cueva Charles Brewer, a large cave in a sandstone tepui, in SE Venezuela. These are the third example of photokarren ever studied in the world, the other two being from Borneo and Ireland. They are the only photokarren ever described from sandstone, and the only example from a non-carbonate environment. The host rock is a poorly-lithified unit of the Precambrian quartz arenite of the Roraima Supergroup. The forms are all oriented towards the light at 30° regardless of rock surface orientation. …


A Unique Population Of Cave Bears (Carnivora: Ursidae) From The Middle Pleistocene Of Kents Cavern, England, Based On Dental Morphometrics, Donald A. Mcfarlane, Martin Sabol, Joyce Lundberg Jan 2010

A Unique Population Of Cave Bears (Carnivora: Ursidae) From The Middle Pleistocene Of Kents Cavern, England, Based On Dental Morphometrics, Donald A. Mcfarlane, Martin Sabol, Joyce Lundberg

WM Keck Science Faculty Papers

The ‘breccia’ stratum from Kents (we follow local tradition in using the form ‘Kents’, without an apostrophe) Cavern, England, has been well known for its rich yield of cave-bear material since excavations began in the mid-19th century. Recent work has established that the bears are of latest MIS 12 or earliest MIS 11 age. A life table based on a collection of 67 molariform teeth is consistent with the use of the cave as a hibernaculum. Univariate and morphological assessment of the teeth shows an unusual range of primitive and more derived characters. Multivariate morphometric analysis of cave-bear teeth from …


A Geographic Information Systems Approach To The 19th Century Excavation Of Brixham Cavern, Devon, England, Donald A. Mcfarlane, Joyce Lundberg, Warren Roberts Jan 2010

A Geographic Information Systems Approach To The 19th Century Excavation Of Brixham Cavern, Devon, England, Donald A. Mcfarlane, Joyce Lundberg, Warren Roberts

WM Keck Science Faculty Papers

The oldest known spatially-explicit archaeological excavation, conducted in Brixham cave, Devon, in 1858, is reconstructed using geographic information systems technology. Two dimensional plots of individual fossil taxa and flint artefacts demonstrate the utility of the technique for elucidating taphonomy and palaeobiology. The cave served as a den for hibernating brown bears, as a den for hyena and cave lion, and as a reliquary for their prey.


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 …


Constructing A Flash Flood Climatology Of The Appalachian Mountains: Comparison Of Eastern Kentucky And West Virginia Summer Time Rain Events, Jane Marie Wix Jan 2010

Constructing A Flash Flood Climatology Of The Appalachian Mountains: Comparison Of Eastern Kentucky And West Virginia Summer Time Rain Events, Jane Marie Wix

Mahurin Honors College Capstone Experience/Thesis Projects

The Appalachian Mountains are subject to flash floods due to interactions between complex terrain and frequent rainfall. Previous studies have shown that a number of environmental factors can trigger flash floods, which can leave behind a variety of outcomes. However, there is a lack of research concerning flash floods in the Appalachian region. This study addresses these concerns by examining summer (June-August) rainfall frequency and intensity in connection with flash floods in the Appalachian region of eastern Kentucky and West Virginia during 1995-2005. Flash floods were identified using the National Climatic Data Center’s (NCDC) Storm Database. Radar estimated rainfall data …


Regional Vs. Local Impact Of Wind On Glaciers In The Andes Mountains, Derek Ferris Jan 2010

Regional Vs. Local Impact Of Wind On Glaciers In The Andes Mountains, Derek Ferris

Undergraduate Review

Northern Peru will face critical water resource issues in the near future as permanent ice in the Andes Mountains continues to rapidly melt. Ironically, the melt-water from these glaciers supports the culture of 100s of thousands of people living at lower elevations, particularly during the dry season, and predictions suggest some glaciers may be gone in less than 100 years. The impact of local warming of “U” shaped valleys running down the dryer western slope of the Andes range is largely disregarded in current climate model predictions because of the complexity of simulating the complex topography. Studies that compare the …


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 …


Tree Rings And Earthquakes, Matthew F. Bekker Jan 2010

Tree Rings And Earthquakes, Matthew F. Bekker

Wasatch Dendroclimatology Research

The lithosphere, earth’s rigid outer shell comprising crust and upper mantle rock, is broken into about 14 tectonic plates (Christopherson 2009) that move a few centimeters per year over superheated, pliable rock underneath. Forces within earth’s interior push, pull and twist the plates in different directions, producing three types of plate boundaries: convergent (colliding with one another), divergent (moving away from one another) and transform (sliding past one another). Earthquakes occur when plates become locked together, building strain between and within them that is suddenly released, sending a burst of seismic waves that cause shaking and displacement of the surface. …


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.


Geology Of The Gordon Natural Area: A Service-Learning Investigation By Students In Ess 405, Petrology, Fall 2009, Leeann Srogi Jan 2010

Geology Of The Gordon Natural Area: A Service-Learning Investigation By Students In Ess 405, Petrology, Fall 2009, Leeann Srogi

Gordon Natural Area Geology Studies Documents

No abstract provided.


Holocene Landscape Response To Seasonality Of Storms In The Mojave Desert, David M. Miller, Kevin M. Schmidt, Shannon A. Mahan, John P. Mcgeehin, Lewis A. Owen, John A. Barron, Frank Lehmkuhl, Rene Lohrer Jan 2010

Holocene Landscape Response To Seasonality Of Storms In The Mojave Desert, David M. Miller, Kevin M. Schmidt, Shannon A. Mahan, John P. Mcgeehin, Lewis A. Owen, John A. Barron, Frank Lehmkuhl, Rene Lohrer

United States Geological Survey: Staff Publications

New optically stimulated and radiocarbon ages for alluvial fan and lake deposits in the Mojave Desert are presented, which greatly improves the temporal resolution of surface processes. The new Mojave Desert climate-landscape record is particularly detailed for the late Holocene. Evidence from ephemeral lake deposits and landforms indicates times of sustained stream flow during a wet interval of the latter part of the Medieval Warm Period at ca. AD 1290 and during the Little Ice Age at ca. AD 1650. The former lakes postdate megadroughts of the Medieval Warm Period, whereas the latter match the Maunder Minimum of the Little …


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. …


Correlation Between Normalized Ddifference Vvegetation Index And Malaria In A Subtropical Rain Forest Undergoing Rapid Anthropogenic Alteration, Nicole M. Wayant, Diego Maldonado, Antonieta Rojas De Arias, Blanca Cousino, Douglas G. Goodin Jan 2010

Correlation Between Normalized Ddifference Vvegetation Index And Malaria In A Subtropical Rain Forest Undergoing Rapid Anthropogenic Alteration, Nicole M. Wayant, Diego Maldonado, Antonieta Rojas De Arias, Blanca Cousino, Douglas G. Goodin

Center for Advanced Land Management Information Technologies: Publications

Time-series of coarse-resolution greenness values derived through remote sensing have been used as a surrogate environmental variable to help monitor and predict occurrences of a number of vector-borne and zoonotic diseases, including malaria. Often, relationships between a remotely-sensed index of greenness, e.g. the normalized difference vegetation index (NDVI), and disease occurrence are established using temporal correlation analysis. However, the strength of these correlations can vary depending on type and change of land cover during the period of record as well as inter-annual variations in the climate drivers (precipitation, temperature) that control the NDVI values. In this paper, the correlation between …


Geochemical And Mineralogical Evidence For Sahara And Sahel Dust Additions To Quaternary Soils On Lanzarote, Eastern Canary Islands, Spain, Daniel R. Muhs, James Budahn, Gary Skipp, Joseph M. Prospero, Deanna Patterson, E. Arthur Bettis Iii Jan 2010

Geochemical And Mineralogical Evidence For Sahara And Sahel Dust Additions To Quaternary Soils On Lanzarote, Eastern Canary Islands, Spain, Daniel R. Muhs, James Budahn, Gary Skipp, Joseph M. Prospero, Deanna Patterson, E. Arthur Bettis Iii

United States Geological Survey: Staff Publications

Africa is the most important source of dust in the world today, and dust storms are frequent on the nearby Canary Islands. Previous workers have inferred that the Sahara is the most important source of dust to Canary Islands soils, with little contribution from the Sahel region. Soils overlying a late Quaternary basalt flow on Lanzarote, Canary Islands, contain, in addition to volcanic minerals, quartz and mica, exotic to the island!s bedrock. Kaolinite in the soils also likely has an exotic origin. Trace-element geochemistry shows that the soils are derived from varying proportions of locally derived basalt and African dust. …


Development And Application Of A Pollen-Based Paleohydrologic Reconstruction From The Lower Roanoke River Basin, North Carolina, Usa, Debra Willard, Christopher Bernhardt, Roger Brown, Bryan Landacre, Philip A. Townsend Jan 2010

Development And Application Of A Pollen-Based Paleohydrologic Reconstruction From The Lower Roanoke River Basin, North Carolina, Usa, Debra Willard, Christopher Bernhardt, Roger Brown, Bryan Landacre, Philip A. Townsend

United States Geological Survey: Staff Publications

We used pollen assemblages to reconstruct late-Holocene paleohydrologic patterns in floodplain deposits from the lower Roanoke River basin (North Carolina, southeastern USA). Using 120 surface samples from 38 transects, we documented statistical relationships between pollen assemblages, vegetation, and landforms. Backswamp pollen assemblages (long hydroperiods) are dominated by Nyssa (tupelo) and Taxodium (cypress) and have high pollen concentrations. Sediments from elevated levees and seasonally flooded forests (shorter hydroperiods) are characterized by dominant Pinus (pine) pollen, variable abundance of hardwood taxa, and low pollen concentrations. We apply the calibration data set to interpret past vegetation and paleohydrology. Pollen from a radiocarbon-dated sediment …


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.


Landscape Values As A Determinant In Geotourism Development: A Case Study Of Utah, Usa, E. Papińska, Elzbieta Białkowska-Jelińska Jan 2010

Landscape Values As A Determinant In Geotourism Development: A Case Study Of Utah, Usa, E. Papińska, Elzbieta Białkowska-Jelińska

School of Geosciences Student Publications

The state of Utah is located in west-central United States. The area of 219 887 km2is populated by 2.8 million people (in 2009). Population density is relatively low: 12 persons per square km. The main reasons for low population density are unfavourable natural conditions. The most important are topography and climate. Utah’s landscape diversity is a consequence of a variety of terrain types. For that reason, there are 5 national parks (Zion, Bryce, Capitol Reef, Arches and Canyonlands), national monuments, and other lower rank protected areas established in Utah. Each of these places, characterized by unique types of …


Geology Of Central Eleuthera, Bahamas: A Field Trip Guide, Pascal Kindler, John E. Mylroie, H. Allen Curran, James L. Carew, Douglas W. Gamble, Thomas A. Rothfus Jan 2010

Geology Of Central Eleuthera, Bahamas: A Field Trip Guide, Pascal Kindler, John E. Mylroie, H. Allen Curran, James L. Carew, Douglas W. Gamble, Thomas A. Rothfus

Geosciences: Faculty Publications

See other Smith authored Field Trip Guides of Gerace Research Centre.


Leading The James: The Morphological Changes Of The Missouri River And The Subservient James River, April Deann Moreno Jan 2010

Leading The James: The Morphological Changes Of The Missouri River And The Subservient James River, April Deann Moreno

Earth & Environmental Sciences Theses - Archive

The James River flows into the Missouri River east of Yankton, SD. The degree to which the morphological changes of the Missouri River had an impact on the course of the James River is debatable. After mapping the Mission Hill and Menominee quadrangles, surficial maps have been made showing the preserved allounits of the area. Hand augers were used to ground-truth surface features located through the use of aerial photographs, topographic maps, and to confirm features on the surficial maps made. OSL samples were taken from both quadrangles and also from Meckling and Saint Helena; the latter two were mapped …


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. …


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 …


Response Of River‐Dominated Delta Channel Networks To Permanent Changes In River Discharge, Doug Edmonds, Rudy Slingerland, Jim Best, Dan Parsons, Norm Smith Jan 2010

Response Of River‐Dominated Delta Channel Networks To Permanent Changes In River Discharge, Doug Edmonds, Rudy Slingerland, Jim Best, Dan Parsons, Norm Smith

Department of Earth and Atmospheric Sciences: Faculty Publications

Using numerical experiments, we investigate how river‐dominated delta channel networks are likely to respond to changes in river discharge predicted to occur over the next century as a result of environmental change. Our results show for a change in discharge up to 60% of the initial value, a decrease results in distributary abandonment in the delta, whereas an increase does not significantly affect the network. However, an increase in discharge beyond a threshold of 60% results in channel creation and an increase in the density of the distributary network. This behavior is predicted by an analysis of an individual bifurcation …


Response Of River‐Dominated Delta Channel Networks To Permanent Changes In River Discharge, Doug Edmonds, Rudy Slingerland, Jim Best, Dan Parsons, Norman D. Smith Jan 2010

Response Of River‐Dominated Delta Channel Networks To Permanent Changes In River Discharge, Doug Edmonds, Rudy Slingerland, Jim Best, Dan Parsons, Norman D. Smith

Department of Earth and Atmospheric Sciences: Faculty Publications

Using numerical experiments, we investigate how river‐dominated delta channel networks are likely to respond to changes in river discharge predicted to occur over the next century as a result of environmental change. Our results show for a change in discharge up to 60% of the initial value, a decrease results in distributary abandonment in the delta, whereas an increase does not significantly affect the network. However, an increase in discharge beyond a threshold of 60% results in channel creation and an increase in the density of the distributary network. This behavior is predicted by an analysis of an individual bifurcation …


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. …


Enhanced Late Holocene Enso/Pdo Expression Along The Margins Of The Eastern North Pacific, John A. Barron, Lesleigh Anderson Jan 2010

Enhanced Late Holocene Enso/Pdo Expression Along The Margins Of The Eastern North Pacific, John A. Barron, Lesleigh Anderson

United States Geological Survey: Staff Publications

Pacific climate is known to have varied during the Holocene, but spatial patterns remain poorly defined. This paper compiles terrestrial and marine proxy data from sites along the northeastern Pacific margins and proposes that they indicate 1) suppressed ENSO conditions during the middle Holocene between ~8000 and 4000 cal BP with a North Pacific that generally resembled a La Niña-like or more negative PDO phase and 2) a climate transition between ~4200 and 3000 cal BP that appears to be the teleconnected expression to a more modern-like ENSO Pacific. Compared to modern day conditions, the compiled data suggest that during …


Green Local Governments In Florida: Assessment Of Sustainability Performance, Naimish Upadhyay, Robert Brinkmann Jan 2010

Green Local Governments In Florida: Assessment Of Sustainability Performance, Naimish Upadhyay, Robert Brinkmann

School of Geosciences Faculty and Staff Publications

The sustainability performance of local governments that adopted the Florida Green Building Coalition’s Green Local Government standard was evaluated using a web-based review and survey of 26 local governments within the context of the Three Es of environment, equity, and economic development. The results indicate that while many local governments exhibit a broad commitment to sustainability as evidenced by the inclusion of sustainability in formal documents, such efforts are not present across all government functions or departments. In addition, while local issues are often addressed, interrelated sustainability goals of equity and economic development are not clearly articulated. Most local governments …


Paleogeographic, Paleoceanographic, And Tectonic Controls On Early Late Ordovician Graptolite Diversity Patterns, Daniel Goldman, Shuang-Ye Wu Jan 2010

Paleogeographic, Paleoceanographic, And Tectonic Controls On Early Late Ordovician Graptolite Diversity Patterns, Daniel Goldman, Shuang-Ye Wu

Department of Earth, Environment and Sustainability Faculty Publications

The Katian Age (early Late Ordovician) was a time of significant decline in marine biodiversity, but whether this decline was a real phenomenon or an artifact of the relatively few studies devoted to this interval requires further research. We examined the pattern of graptolite faunal changes across the boundary between the Climacograptus bicornis and Diplacanthograptus caudatus graptolite zones in North America and on several other continents.

A sharp decline in species diversity occurs in the Appalachian Basin. Scores for normalized diversity dropped from 20 in the C. bicornis Zone to 7 in the D. caudatus Zone. Only 11% of the …


The Impact Of Tsunamis On The Island Of Majorca Induced By North Argelian Seismic Sources, José A. Álvarez-Gómez, Maitane Olabarrieta, Mauricio González, Luís Otero, Emilio Carreño, José M. Martínez-Solares Jan 2010

The Impact Of Tsunamis On The Island Of Majorca Induced By North Argelian Seismic Sources, José A. Álvarez-Gómez, Maitane Olabarrieta, Mauricio González, Luís Otero, Emilio Carreño, José M. Martínez-Solares

Turkish Journal of Earth Sciences

The north of Algeria is the main earthquake-related tsunami generation zone that threatens the Balearic Islands. In this work we review the major seismic series of the area -the 1980 El Asnam and the 2003 Boumerdes-Zemmouri earthquakes– in order to obtain a probable worst characteristic earthquake rupture. We estimate rupture dimensions of 55 km x 16 km, reaching the fault plane a depth of 13 km. The dip and rake have been taken as constants, with values of 50° and 90° respectively, while the strike is adjusted to the local tectonic structure. With these characteristics a magnitude M_w= 7.3 earthquake …


Morphology, Taxonomy And Lifestyle Of The Maastrichtian Rudist Bivalve Thyrastylon, Simon Francis Mitchell Jan 2010

Morphology, Taxonomy And Lifestyle Of The Maastrichtian Rudist Bivalve Thyrastylon, Simon Francis Mitchell

Turkish Journal of Earth Sciences

The rudist bivalve Thyrastylon is redescribed based on extensive material collected from Jamaica. The new material shows that the left valve contains slits, and that this is the diagnostic feature of the genus. The genus is redefined as follows: a radiolitid rudist with no ligamental infold, stretched cellular microstructure and compact layers in the outer layer of the right valve; the radial bands are partially infolded into the shell layer of the right valve; the left valve has oscules developed above the radial bands and has concentric, slit-like pores that penetrate the shell and open out onto the inner part …