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Progressive Abandonment And Planform Changes Of The Central Platte River In Nebraska, Central Usa, Over Historical Timeframes, John D. Horn, R. Matthew Joeckel, Christopher R. Fielding Jan 2012

Progressive Abandonment And Planform Changes Of The Central Platte River In Nebraska, Central Usa, Over Historical Timeframes, John D. Horn, R. Matthew Joeckel, Christopher R. Fielding

Department of Earth and Atmospheric Sciences: Faculty Publications

This paper presents data compiled from aerial photography, General Land Office maps (GLOs), and discharge data from the central Platte River in Nebraska that quantify and provide a new understanding of channel evolution and abandonment in a braided stream. Analyses of aerial photographs and GLOs in ArcMap™ show that channel area decreased by an average of 46% from 1938 to 2006 and that channel widths in 1858 were an average of 539% greater than in 2006. Annual discharge during 1942–2006 does not show a clear long-term relationship with the decrease in channel width and area. Rather, stabilization through vegetation of …


Holocene Seasonal Variability Inferred From Multiple Proxy Records From Crevice Lake, Yellowstone National Park, Usa, Cathy Whitlock, Walter E. Dean, Sherilyn C. Fritz, Lora R. Stevens, Jeffery R. Stone, Mitchell J. Power, Joseph R. Rosenbaum, Kenneth L. Pierce, Brandi B. Bracht-Flyr Jan 2012

Holocene Seasonal Variability Inferred From Multiple Proxy Records From Crevice Lake, Yellowstone National Park, Usa, Cathy Whitlock, Walter E. Dean, Sherilyn C. Fritz, Lora R. Stevens, Jeffery R. Stone, Mitchell J. Power, Joseph R. Rosenbaum, Kenneth L. Pierce, Brandi B. Bracht-Flyr

Department of Earth and Atmospheric Sciences: Faculty Publications

A 9400-yr-old record from Crevice Lake, a semi-closed alkaline lake in northern Yellowstone National Park, was analyzed for pollen, charcoal, geochemistry, mineralogy, diatoms, and stable isotopes to develop a nuanced understanding of Holocene environmental history in a region of northern Rocky Mountains that receives both summer and winter precipitation. The limited surface area, conical bathymetry, and deep water (>31 m) of Crevice Lake create oxygen-deficient conditions in the hypolimnion and preserve annually laminated sediment (varves) for much of the record. Pollen data indicate that the watershed supported a closed Pinus-dominated forest and low fire frequency prior to 8200 …


Three Geologic Cross Sections Across Portions Of Eastern Nebraska Showing Quaternary Lithologic Units And Stratigraphy Of Uppermost Bedrock, Jesse T. Korus, Dana Divine, P. R. Hanson, J. S. Dillon Jan 2012

Three Geologic Cross Sections Across Portions Of Eastern Nebraska Showing Quaternary Lithologic Units And Stratigraphy Of Uppermost Bedrock, Jesse T. Korus, Dana Divine, P. R. Hanson, J. S. Dillon

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Global Air Temperature Variability Independent Of Sea-Surface Temperature Influences, Andrew C. Comrie, Gregory J. Mccabe Jan 2012

Global Air Temperature Variability Independent Of Sea-Surface Temperature Influences, Andrew C. Comrie, Gregory J. Mccabe

United States Geological Survey: Staff Publications

Mean global surface air temperature (SAT) and sea surface temperature (SST) display substantial variability on timescales ranging from annual to multi-decadal. We review the key recent literature on connections between global SAT and SST variability. Although individual ocean influences on SAT have been recognized, the combined contributions of worldwide SST variability on the global SAT signal have not been clearly identified in observed data.Weanalyze these relations using principal components of detrended SST, and find that removing the underlying combined annual, decadal, and multi-decadal SST variability from the SAT time series reveals a nearly monotonic global warming trend in SAT since …


History And Evaluation Of National-Scale Geochemical Data Sets For The United States, David B. Smith, Steven M. Smith, John D. Horton Jan 2012

History And Evaluation Of National-Scale Geochemical Data Sets For The United States, David B. Smith, Steven M. Smith, John D. Horton

United States Geological Survey: Staff Publications

Six national-scale, or near national-scale, geochemical data sets for soils or stream sediments exist for the United States. The earliest of these, here termed the ‘Shacklette’ data set, was generated by a U.S. Geological Survey (USGS) project conducted from 1961 to 1975. This project used soil collected from a depth of about 20 cm as the sampling medium at 1323 sites throughout the conterminous U.S. The National Uranium Resource Evaluation Hydrogeochemical and Stream Sediment Reconnaissance (NUREHSSR) Program of the U.S. Department of Energy was conducted from 1975 to 1984 and collected either stream sediments, lake sediments, or soils at more …


Shoreline Changes In Point Pelee, Canada: An Airphoto-Based Analysis, Abdullah Bamasoud Jan 2012

Shoreline Changes In Point Pelee, Canada: An Airphoto-Based Analysis, Abdullah Bamasoud

Theses and Dissertations (Comprehensive)

Shoreline retreat has significant consequences for Point Pelee National Park’s (PPNP) ecological and economic systems. In this study, the shoreline changes of PPNP are examined in terms of their rates, their relationship to natural and anthropogenic influences, and methods for predicting shoreline positions.

The rates of shoreline change are analyzed for the period 1959-2004 using ortho-airphotos. The eastern shoreline of the Park exhibited varying recession in both rising and falling Lake Erie water level, especially in the Northeast Beach, where it averaged -3.14 m˖y-1. The western shoreline of the Park generally exhibited accretion and had an inverse relationship with Lake …


Landscape-Level Controls On Dissolved Carbon Flux From Diverse Catchments Of The Circumboreal, Suzanne E. Tank, Karen E. Frey, Robert G. Striegl, Peter A. Raymond, Robert M. Holmes, James W. Mcclelland, Bruce J. Peterson Jan 2012

Landscape-Level Controls On Dissolved Carbon Flux From Diverse Catchments Of The Circumboreal, Suzanne E. Tank, Karen E. Frey, Robert G. Striegl, Peter A. Raymond, Robert M. Holmes, James W. Mcclelland, Bruce J. Peterson

Geography

While much of the dissolved organic carbon (DOC) within rivers is destined for mineralization to CO2, a substantial fraction of riverine bicarbonate (HCO3-) flux represents a CO2 sink, as a result of weathering processes that sequester CO2 as HCO 3-. We explored landscape-level controls on DOC and HCO3- flux in subcatchments of the boreal, with a specific focus on the effect of permafrost on riverine dissolved C flux. To do this, we undertook a multivariate analysis that partitioned the variance attributable to known, key regulators of dissolved C flux (runoff, lithology, and vegetation) prior to examining the effect of permafrost, …


New Methods For The Discovery And Characterization Of Lunar Lava Tubes Using Lunar Reconnaissance Orbiter Data, Jonathan Arthur Meyer Jan 2012

New Methods For The Discovery And Characterization Of Lunar Lava Tubes Using Lunar Reconnaissance Orbiter Data, Jonathan Arthur Meyer

Open Access Theses & Dissertations

Lava tubes have the potential to serve as a sustainable solution to long-term lunar habitation by providing protection from radiation and micrometeorite bombardment while potentially providing resources in the form of trapped water ice. They also pose compelling science targets in their own right. While the potential benefits of utilizing lunar lava tubes is clear, their discovery is less straightforward. Formation processes for lava tubes do not always result in a surface expression, making their discovery using remotely sensed imagery difficult. Furthermore, there is the potential for lava tubes to be covered by secondary lava flows, impact ejecta, or other …


Vertical Deformation Along The San Andreas Fault, Garrett Thornton Jan 2012

Vertical Deformation Along The San Andreas Fault, Garrett Thornton

Open Access Theses & Dissertations

There have been numerous M 6+ earthquakes along the San Andreas Fault System (SAFS) (Schwartz et al., 1984) (Figure. 1.1) in the historical past. These rupture events have created millions of dollars worth of damage, and have been responsible for multiple lives lost. An improved understanding of the motions and crustal characteristics along the SAFS can lead to better hazard mitigation (Bakun et al., 2005). Horizontal crustal motions of the SAFS have been widely studied and applied to seismic hazard models (WGCEP, 2007), however vertical motions are not often utilized due to their complicated origin and sometimes large uncertainties. This …


Constraints On The Structure Of The Border Ranges Fault System, South-Central Alaska From Integrated 3d Inversion Of Gravity/Magnetic Data, Niti Mankhemthong Jan 2012

Constraints On The Structure Of The Border Ranges Fault System, South-Central Alaska From Integrated 3d Inversion Of Gravity/Magnetic Data, Niti Mankhemthong

Open Access Theses & Dissertations

I use updated gravity data, available aeromagnetic data, and other geophysical information as constraints to develop 2D and 3D structural models of density and magnetic susceptibility to better locate and determine the shape of the Border Ranges fault system (BRFS), the Border Range ultramafic and mafic assemblages and other forearc-arc boundary structures in south-central Alaska, that have previously been studied in only limited detail. There are three geophysical research projects that form the chapters of the dissertation. First, I estimated near-surface density variations in the central Kenai Peninsula based on the adaptation of the Nettleton (1939)-Parasnis (1952) method using Tarantola …


Use Of Environmental Isotope Tracer And Gis Techniques To Estimate Basin Recharge, Abdulganiu A.A. Odunmbaku Jan 2012

Use Of Environmental Isotope Tracer And Gis Techniques To Estimate Basin Recharge, Abdulganiu A.A. Odunmbaku

Open Access Theses & Dissertations

The extensive use of ground water only began with the advances in pumping technology at the early portion of 20th Century. Groundwater provides the majority of fresh water supply for municipal, agricultural and industrial uses, primarily because of little to no treatment it requires. Estimating the volume of groundwater available in a basin is a daunting task, and no accurate measurements can be made. Usually water budgets and simulation models are primarily used to estimate the volume of water in a basin.

Precipitation, land surface cover and subsurface geology are factors that affect recharge; these factors affect percolation which invariably …


The Impact Of Decadal Land Cover Change On The Global Warming Potential Of Beringian Arctic Tundra, David Hwei-Len Lin Jan 2012

The Impact Of Decadal Land Cover Change On The Global Warming Potential Of Beringian Arctic Tundra, David Hwei-Len Lin

Open Access Theses & Dissertations

Arctic terrestrial ecosystems play an important role in the global carbon cycle. If arctic warming continues to rise as projected, large amounts of soil carbon stored in these ecosystems could be released to the atmosphere as carbon dioxide or methane and positively enhance greenhouse warming. Thus, improving understanding of the likely future state and fate of arctic soil carbon, and the carbon uptake potential of arctic terrestrial ecosystems are well recognized research priorities.

At the pan-arctic scale, decadal increases in NDVI (Normalized Difference Vegetation Index), an index of vegetation productivity, have been observed from satellite imagery, indicating a general greening …


Climate Change At The Pleistocene-Holocene Boundary In The Pacific Northwest: A Comparison Of Proxy Datasets And The Archaeologicial Record, Tiffany J. Fulkerson Jan 2012

Climate Change At The Pleistocene-Holocene Boundary In The Pacific Northwest: A Comparison Of Proxy Datasets And The Archaeologicial Record, Tiffany J. Fulkerson

EWU Masters Thesis Collection

"The relationship between climate change at the Pleistocene-Holocene Boundary (ca. 12,600-10,200 cal B.P.) and cultural responses to attendant shifts in the environment remains a vexing issue for archaeologists. This study compiles and analyzes glacial, palynological, faunal, and stratigraphic/geomorphological proxy datasets for climate change in the Pacific Northwest of North America and compares them to the coeval archaeological record. The primary purpose of this exercise is to consider the potential ways in which climate change at the Pleistocene-Holocene Boundary affected cultural development for Late Paleoindian-Early Archaic peoples in the Pacific Northwest. Results indicate that climatic and environmental change at this interval …


Controls On Dissolved Cobalt In Surface Waters Of The Sargasso Sea: Comparisons With Iron And Aluminum, R. U. Shelley, Peter N. Sedwick, T. S. Bibby, P. Cabedo-Sanz, T. M. Church, R. J. Johnson, A. I. Macey, C. M. Marsay, E. R. Sholkovitz, S. J. Ussher, P. J. Worsfold, M. C. Lohan Jan 2012

Controls On Dissolved Cobalt In Surface Waters Of The Sargasso Sea: Comparisons With Iron And Aluminum, R. U. Shelley, Peter N. Sedwick, T. S. Bibby, P. Cabedo-Sanz, T. M. Church, R. J. Johnson, A. I. Macey, C. M. Marsay, E. R. Sholkovitz, S. J. Ussher, P. J. Worsfold, M. C. Lohan

OES Faculty Publications

Dissolved cobalt (dCo), iron (dFe) and aluminum (dAl) were determined in water column samples along a meridional transect (∼31°N to 24°N) south of Bermuda in June 2008. A general north-to-south increase in surface concentrations of dFe (0.3-1.6 nM) and dAl (14-42 nM) was observed, suggesting that aerosol deposition is a significant source of dFe and dAl, whereas no clear trend was observed. for near-surface dCo concentrations. Shipboard aerosol samples indicate fractional solubility values of 8-100% for aerosol Co, which are significantly higher than corresponding estimates of the solubility of aerosol Fe (0.44-45%). Hydrographic observations and analysis of time series rain …


Stability Of Rock Slopes Along Raidah Escarpment Road, Asir Area, Kingdom Of Saudi Arabia, Ahmed M. Youssef, Norbert H. Maerz, Abdulla A. Al-Otaibi Jan 2012

Stability Of Rock Slopes Along Raidah Escarpment Road, Asir Area, Kingdom Of Saudi Arabia, Ahmed M. Youssef, Norbert H. Maerz, Abdulla A. Al-Otaibi

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Raidah Escarpment road is located north west of Abha city, Asir region, Kingdom of Saudi Arabia. This escarpment road represents an important corridor in the area which connects different villages and tourist resorts with each other. The total length of this road section is about 9 km which passes through a highly mountainous area. The road also passes through areas of different geological hazards (rock, debris flow, soil, and weathered zones). The different environmental factors (e.g. intensive rainy summer), variable geological and structural elements (weak rocks, slide debris weak soils, shear zones, and faults) difficult road characteristics (narrow roads …


Systematics, Diversity, And Origins Of Upper Cretaceous Continental Molluscan Fauna In The Infra- And Intertrappean Strata Of The Deccan Plateau, Central India, Marron J. Bingle-Davis Jan 2012

Systematics, Diversity, And Origins Of Upper Cretaceous Continental Molluscan Fauna In The Infra- And Intertrappean Strata Of The Deccan Plateau, Central India, Marron J. Bingle-Davis

Theses and Dissertations

The Deccan Plateau in western and central India has been a major area of interest for researchers since the 1800s. In 1840, James Sowerby described the molluscan collection sent to him by John Malcolmson. In 1860, Stephen Hislop identified new molluscan species and redescribed based on better preserved material. Although this seminal work was comprehensive, interpretations have changed since the mid 1800s. Species need to be reassigned to current and/or accurate taxa, as well as revalidated statistically. Seventeen character traits were measured on over 600 specimens from five eastern Deccan Plateau localities representing a stratigraphic and temporal sequence. Cluster analysis …


Bacterial Community Survey Of Sediments At Naracoorte Caves, Australia, Eric M. Adetutu, Krystal Thorpe, Esmaeil Shahsavari, Steven Bourne, Xiangsheng Cao, Ramin Mazaheri Nezhad Fard, Greg Kirby, Andrew S. Ball Jan 2012

Bacterial Community Survey Of Sediments At Naracoorte Caves, Australia, Eric M. Adetutu, Krystal Thorpe, Esmaeil Shahsavari, Steven Bourne, Xiangsheng Cao, Ramin Mazaheri Nezhad Fard, Greg Kirby, Andrew S. Ball

International Journal of Speleology

Bacterial diversity in sediments at UNESCO World Heritage listed Naracoorte Caves was surveyed as part of an investigation carried out in a larger study on assessing microbial diversity in caves. Cave selection was based on tourist accessibility; Stick Tomato and Alexandra Cave (> 15000 annual visits) and Strawhaven Cave was used as control (no tourist access). Microbial analysis showed that Bacillus was the most commonly detected microbial genus by culture dependent and independent survey of tourist accessible and inaccessible areas of show (tourist accessible) and control caves. Sediment bacterial groups were assigned to the Firmicutes, Actinobacteria and Proteobacteria. The survey …


Climb To The Ice, Richard Vaughan Jan 2012

Climb To The Ice, Richard Vaughan

Articles by Maurer Faculty

The article, originally presented as a lecture, discusses George Bird Grinnell's 1887 climb of the Montana glacier that eventually become known as Grinnell Glacier. Grinnell’s efforts to establish Glacier National Park are detailed. Grinnell's previously unpublished descriptions of the glacier and its surrounding area are analyzed by the author.

Originally delivered as a lecture at the Montana History Conference, October 2, 2010. Full issue available at: http://issuu.com/um_crown_gye/docs/crownofthecontinent-autumn2012


Evaluation Of Pleistocene To Holocene (Mis 5 To 1) Climatic Changes In Southwestern Black Sea: A Palynological Study Of Dsdp Site 380, Shannon Ferguson Jan 2012

Evaluation Of Pleistocene To Holocene (Mis 5 To 1) Climatic Changes In Southwestern Black Sea: A Palynological Study Of Dsdp Site 380, Shannon Ferguson

LSU Master's Theses

Site 380 of the Deep Sea Drilling Program [DSDP] is located in the southwestern region of the Black Sea (42°05.94’, 29°36.82’E). The location of this site is important due to its proximity to the narrow Bosphorus strait, the only present-day connection between the Black Sea and the Aegean Sea. Drops in eustatic sea level during extensive Pleistocene glacial episodes disconnected the Black Sea from the Aegean Sea at the Bosphorus strait, creating a change from brackish to freshwater within the Black Sea during these intervals. Organic-walled phytoplankton (dinoflagellate cysts, acritarchs, and fresh-water algae) are investigated to better constrain these glacio-eustatic …


Glacial Deposits, Vol. 40, 2011-2012, Department Of Geography-Geology Jan 2012

Glacial Deposits, Vol. 40, 2011-2012, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Mapping And Assessing Urban Impervious Areas Using Multiple Endmember Spectral Mixture Analysis: A Case Study In The City Of Tampa, Florida, Fenqing Weng Jan 2012

Mapping And Assessing Urban Impervious Areas Using Multiple Endmember Spectral Mixture Analysis: A Case Study In The City Of Tampa, Florida, Fenqing Weng

USF Tampa Graduate Theses and Dissertations

The advance in remote sensing technology helps people more easily assess urban growth. In this study, the utility of multiple endmember spectral mixture analysis (MESMA) is examined in a sub-pixel analysis of Landsat Thematic Mapper (TM) imagery to map urban physical components in Tampa, FL. The three physical components of urban land cover (LC): impervious surface, vegetation and soil, were compared using the proposed MESMA with a traditional spectral mixture analysis (SMA). MESMA decomposes each pixel to address the heterogeneity of urban LC characteristic by allowing the number and types of endmembers to vary on a per pixel basis. This …


New Science, Synthesis, Scholarship, And Strategic Vision For Society, David R. Foster, Emery Boose, Elizabeth A. Colburn, Elizabeth E. Crone, Aaron M. Ellison, Clarisse Hart, Kathy Fallon Lambert, David A. Orwig, Julie Pallant, Pamela M. Snow, Kristina A. Stinson, Dianna L. Doucette, Paul R. Moorcroft, Andrew D. Richardson, J. William Munger, Adrien C. Finzi, Lucy Hutyra, Anne Short, Brian Donahue, Christopher A. Williams, William V. Sobczak, W. Wyatt Oswald, Edward K. Faison, Jerry M. Melillo, Jonathan R. Thompson, Jeffrey L. Blanchard, Elizabeth S. Chilton, Kristen M. Deangelis, Stephen Destefano, David B. Kittredge, Serita D. Frey, Scott V. Ollinger, Eric A. Davidson Jan 2012

New Science, Synthesis, Scholarship, And Strategic Vision For Society, David R. Foster, Emery Boose, Elizabeth A. Colburn, Elizabeth E. Crone, Aaron M. Ellison, Clarisse Hart, Kathy Fallon Lambert, David A. Orwig, Julie Pallant, Pamela M. Snow, Kristina A. Stinson, Dianna L. Doucette, Paul R. Moorcroft, Andrew D. Richardson, J. William Munger, Adrien C. Finzi, Lucy Hutyra, Anne Short, Brian Donahue, Christopher A. Williams, William V. Sobczak, W. Wyatt Oswald, Edward K. Faison, Jerry M. Melillo, Jonathan R. Thompson, Jeffrey L. Blanchard, Elizabeth S. Chilton, Kristen M. Deangelis, Stephen Destefano, David B. Kittredge, Serita D. Frey, Scott V. Ollinger, Eric A. Davidson

Faculty Publications

Harvard Forest LTER (HFR) is a two decade-strong, integrated research and educational program investigating responses of forest dynamics to natural and human disturbances and environmental changes over broad spatial and temporal scales. HFR engages >30 researchers, >200 graduate and undergraduate students, and dozens of institutions in research into fundamental and applied ecological questions of national and international relevance. Through LTER I–IV, HFR has added historical perspectives, expanded its scope to the New England region, integrated social, biological, and physical sciences, and developed education and outreach programs for K-12, undergraduate, and graduate students, along with managers, decision-makers, and media professionals.


Active Tectonics And Earthquake Destructions In Caves Of Northern And Central Switzerland, Arnfried Becker, Philipp Häuselmann, Jost Eikenberg, Eric Gilli Jan 2012

Active Tectonics And Earthquake Destructions In Caves Of Northern And Central Switzerland, Arnfried Becker, Philipp Häuselmann, Jost Eikenberg, Eric Gilli

International Journal of Speleology

The present publication focuses on the study of caves in northern and central Switzerland in order to detect and date historical earthquakes and active tectonic displacements by investigations of broken and resealed or displaced speleothems datable by U/Th and 14C. While it can be shown that these methods are potentially suitable, the ages obtained are often beyond the range of historically recorded earthquakes, and it cannot be proved that the observed and dated events are related to a seismic event. Particularly this is true for the caves in central Switzerland, where most ages in the Melchsee-Frutt region were beyond …


Identifying The Link Between Lineament And Cave Passage Trends To Comprehend Fractures Continuity And Influence On The Kinta Valley Karst System, Solomon Kassa, Bernard Pierson, Weng S. Chow, Jasmi B. Ab. Talib Jan 2012

Identifying The Link Between Lineament And Cave Passage Trends To Comprehend Fractures Continuity And Influence On The Kinta Valley Karst System, Solomon Kassa, Bernard Pierson, Weng S. Chow, Jasmi B. Ab. Talib

International Journal of Speleology

The Kinta Valley karst landscape is characterised by residual limestone hills scattered all over the valley. The aim of this study is to ascertain the link between lineament and cave passage orientations, and to identify the main fracture controlling the karst features. To achieve that, standard cave surveying and direct lineament extraction techniques, from a 2.5m resolution spot image, were employed. Six trends of lineaments were obtained from the remnant limestone hills, and their main orientation appears to be in the NNW-SSE. Similarly, various caves were surveyed and mapped; their passage orientation analyses reveal that NNW-SSE is the prominent direction. …


A New Karren Feature: Hummocky Karren, Lukas Plan, Christa Renetzeder, Rudolf Pavuza, Wilfried Körner Jan 2012

A New Karren Feature: Hummocky Karren, Lukas Plan, Christa Renetzeder, Rudolf Pavuza, Wilfried Körner

International Journal of Speleology

Karren are small-scale landforms on karst surfaces and many types have been described so far. Here we present an apparently new feature which was found on the Hochschwab karst massive in the Northern Calcareous Alps of Austria. So far only few outcrops each having less than 1 m² within a very restricted area have been found. Morphometric analysis reveals that the karren consist of a randomly distributed, dispersed assemblage of small hummocks and depressions in between. The mean distance between neighbouring hummocks is 4 to 5 cm and the mean height is 0.85 cm. Longitudinal sections are gently sinuous. The …


Diversity And Community Assembly Patterns Of Epigean Vs. Troglobiont Spiders In The Iberian Peninsula, Pedro Cardoso Jan 2012

Diversity And Community Assembly Patterns Of Epigean Vs. Troglobiont Spiders In The Iberian Peninsula, Pedro Cardoso

International Journal of Speleology

Cave-obligate organisms usually have smaller ranges and their assemblages have higher beta diversity than their epigean counterparts. Phylogenetic and functional diversity is usually low in cave communities, leading to taxonomic and functional disharmony, with entire groups missing from the subterranean realm. The objective of this work is to compare range, beta diversity, phylogenetic and functional diversity, taxonomic and functional disharmony of epigean versus troglobiont spiders in the Iberian Peninsula.

The median extent of occurrence was found to be 33 times higher for epigean than for cave species. Beta diversity was significantly higher for troglobiont assemblages. Cave assemblages present lower phylogenetic …


Corrosion Of Limestone Tablets In Sulfidic Ground-Water: Measurements And Speleogenetic Implications, Sandro Galdenzi Jan 2012

Corrosion Of Limestone Tablets In Sulfidic Ground-Water: Measurements And Speleogenetic Implications, Sandro Galdenzi

International Journal of Speleology

The measurement of the weight loss in limestone tablets placed in the Grotta del Fiume (Frasassi, Italy) provided data on the rate of limestone dissolution due to the sulfidic water and on the influence of local environmental conditions.

A linear average corrosion rate of 24 mm ka-1 was measured in stagnant water, while the values were higher (68-119 mm ka-1) where the hydrologic conditions facilitate water movement and gas exchanges. In these zones the increase in water aggressivity is due to mixing with descending, O2-rich, seepage water and is also favored by easier gas exchange …


In Defense Of A Fluctuating-Interface, Particle-Accretion Origin Of Folia, Donald G. Davis Jan 2012

In Defense Of A Fluctuating-Interface, Particle-Accretion Origin Of Folia, Donald G. Davis

International Journal of Speleology

Two recent papers have proposed radically different modes of origin for cave folia. Audra et al. (2009) propose subaqueous origin of carbonate folia via hypogenic CO2 bubble trapping, with concurrent condensation-corrosion and evaporative precipitation within individual folia gas pockets. Queen (2009) proposes that at least some folia are analogous to suboceanic tufa-tower "flanges" and may result from subaqueous freshwater mixing into a briny environment. The purpose of this paper is to show that neither of these mechanisms can be the fundamental process responsible for folia morphology in cave deposits, and that accretion from adherent particles at fluctuating interfaces is …


Spatially Dense Drip Hydrological Monitoring And Infiltration Behaviour At The Wellington Caves, South East Australia, Catherine N. Jex, Gregoire Mariethoz, Andy Baker, Peter Graham, Martin S. Andersen, Ian Acworth, Nerilee Edwards, Cecilia Azcurra Jan 2012

Spatially Dense Drip Hydrological Monitoring And Infiltration Behaviour At The Wellington Caves, South East Australia, Catherine N. Jex, Gregoire Mariethoz, Andy Baker, Peter Graham, Martin S. Andersen, Ian Acworth, Nerilee Edwards, Cecilia Azcurra

International Journal of Speleology

Despite the fact that karst regions are recognised as significant groundwater resources, the nature of groundwater flow paths in the unsaturated zone of such fractured rock is at present poorly understood. Many traditional methods for constraining groundwater flow regimes in karst aquifers are focussed on the faster drainage components and are unable to inform on the smaller fracture or matrix-flow components of the system. Caves however, offer a natural inception point to observe both the long term storage and the preferential movement of water through the unsaturated zone of such fractured carbonate rock by monitoring of drip rates of stalactites, …


Cryogenic Fracturing Of Calcite Flowstone In Caves: Theoretical Considerations And Field Observations In Kents Cavern, Devon, Uk., Joyce Lundberg, Donald A. Mcfarlane Jan 2012

Cryogenic Fracturing Of Calcite Flowstone In Caves: Theoretical Considerations And Field Observations In Kents Cavern, Devon, Uk., Joyce Lundberg, Donald A. Mcfarlane

International Journal of Speleology

Several caves in Devon, England, have been noted for extensive cracking of substantial flowstone floors. Conjectural explanations have included earthquake damage, local shock damage from collapsing cave passages, hydraulic pressure, and cryogenic processes. Here we present a theoretical model to demonstrate that frost-heaving and fracture of flowstone floors that overlie wet sediments is both a feasible and likely consequence of unidirectional air flow or cold-air ponding in caves, and argue that this is the most likely mechanism for flowstone cracking in caves located in Pleistocene periglacial environments outside of tectonically active regions. Modeled parameters for a main passage in Kents …