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Articles 511 - 540 of 1754

Full-Text Articles in Geology

Caves In Caves: Evolution Of Post-Depositional Macroholes In Stalagmites, Nurit Shtober-Zisu, Henry P. Schwarcz, Tom Chow, Christopher R. Omelon, Gordon Southam Sep 2014

Caves In Caves: Evolution Of Post-Depositional Macroholes In Stalagmites, Nurit Shtober-Zisu, Henry P. Schwarcz, Tom Chow, Christopher R. Omelon, Gordon Southam

International Journal of Speleology

In a previous paper (Shtober-Zisu et al., 2012) we described millimeter to centime-sized fluid-free holes within the interiors of stalagmites of widely varying origin. We present here further observations of this phenomenon, using X-ray tomography, macroscopic and microscopic observation of sections of twenty-six stalagmites from various sites in North America and the Caribbean region. We can distinguish three types of cavities in speleothems: primary µm-sized fluid inclusions; mm to cm sized holes, aligned along the stalagmite growth axis which are clearly syngenetic; and µm to cm-sized holes away from the growth axis (“off-axis holes or OAHs”) deeply buried inside their …

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Remote Exploration: Understanding Martian Surface Processes, Sarah M. Bass, Virginia C. Gulick, Natalie Glines, Patrick Freeman Aug 2014

Remote Exploration: Understanding Martian Surface Processes, Sarah M. Bass, Virginia C. Gulick, Natalie Glines, Patrick Freeman

STAR Program Research Presentations

Earth and Mars share many similar physical features, including canyons, valleys, craters, volcanoes, ice, and gullies. My research focuses on two distinct projects. The first concentrates on the formation of gullies, which are channel networks generally formed on mid-latitude crater walls on Mars. Debated gully-forming processes include the melting of snowpacks, sublimation of accumulated carbon dioxide frost, melting of snow-rich dusty mantle material, and groundwater flows. Using High Resolution Imaging Science Experiment (HiRISE) images of gullies and working with Digital Elevation Models (DEMs) in ENVI, we are able to perform detailed studies of gully morphology, including volume calculations using slope, …

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Climate Study In An Abandoned Auto Tunnel In Alaska, Usa, Andreas Pflitsch, David Holmgren Aug 2014

Climate Study In An Abandoned Auto Tunnel In Alaska, Usa, Andreas Pflitsch, David Holmgren

The International Workshop on Ice Caves

An abandoned auto tunnel in south central Alaska in an elevation of 118 m above sea level seemed to be a perfect laboratory for studying the evolution of ice speleothems in a yearly cycle. More than 1,500 ice forms like stalagmites, stalactites, columns in various shape and arrangements, developed in just 2 month to a high up to 6 meters and lasted for another 5 to 6 month. In October just the remains of the melted ice in rings and rectangular patterns of a white powder could be found. Unfortunately the mostly sealed tunnel was opened in January 2014 by …

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The Monica (Monitoring Of Ice Within Caves) Project: A Multidisciplinary Approach For The Geophysical And Paleoclimatic Characterization Of Permanent Ice Deposits In The Southeastern Alps, Renato R. Colucci, Emanuele Forte, Barbara Stenni, Marco Basso Bondini, Mauro Colle Fontana, Costanza Del Gobbo, Daniele Fontana, Doriana Belligoi, Valter Maggi, Marco Filipazzi Aug 2014

The Monica (Monitoring Of Ice Within Caves) Project: A Multidisciplinary Approach For The Geophysical And Paleoclimatic Characterization Of Permanent Ice Deposits In The Southeastern Alps, Renato R. Colucci, Emanuele Forte, Barbara Stenni, Marco Basso Bondini, Mauro Colle Fontana, Costanza Del Gobbo, Daniele Fontana, Doriana Belligoi, Valter Maggi, Marco Filipazzi

The International Workshop on Ice Caves

On days 30 September and 1-2 October 2013, a 7.8 m long ice core has been extracted from a permanent ice cave deposit in the Southeastern Alps (Vasto’s cave, Mt.Canin - Julian Alps). Each 20 to 100 cm long section of the ice core have been immediately stored in plastic bags and preserved thanks to dry ice. The ice samples, thanks to the helicopter, has been subsequently brought on valley and promptly stored in a refrigerated van, made available by BoFrost. Thus the ice cores has been transported intact to the EUROCOLD laboratory in Milan. These operations have been carried …

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Characterization Of Two Permanent Ice Cave Deposits In The Southeastern Alps (Italy) By Means Of Ground Penetrating Radar (Gpr), Renato R. Colucci, Daniele Fontana, Emanuele Forte Aug 2014

Characterization Of Two Permanent Ice Cave Deposits In The Southeastern Alps (Italy) By Means Of Ground Penetrating Radar (Gpr), Renato R. Colucci, Daniele Fontana, Emanuele Forte

The International Workshop on Ice Caves

In order to assess the thickness and the inner structure of some permanent ice deposits in two high elevated alpine karstic caves of the Canin massif (Alpi Giulie, Italy), we performed several multi frequency Ground Penetrating Radar (GPR) surveys. The surveys have been conducted within the project MONICA (MOnitoring of Ice within Caves), aimed at the paleoclimatic characterization of the considered cave ice deposits. GPR surveys have proved to be crucial also in finding the most suitable place for carrying out a drilling core. This has been particularly useful in the Vasto’s ice cave (VIC) in which the direct/visual estimation …

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New Research In Cave Ledenica In Bukovi Vrh On Velebit Mt In Croatian Dinaric Karst, Mladen Garasic Aug 2014

New Research In Cave Ledenica In Bukovi Vrh On Velebit Mt In Croatian Dinaric Karst, Mladen Garasic

The International Workshop on Ice Caves

No abstract provided.

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Evolution And Equilibration Of Artificial Morphologic Perturbations In The Form Of Nearshore Berm Nourishments Along The Florida Gulf Coast, Katherine Emily Brutsché Jun 2014

Evolution And Equilibration Of Artificial Morphologic Perturbations In The Form Of Nearshore Berm Nourishments Along The Florida Gulf Coast, Katherine Emily Brutsché

USF Tampa Graduate Theses and Dissertations

Inlets and channels are dredged often to maintain navigation safety. It is beneficial to reintroduce the dredged material back into the littoral system, in the form of beach or nearshore nourishments. Nourishment in the nearshore is becoming an increasingly utilized method, particularly for dredged material that contains more fine sediment than the native beach. This research examines the morphologic evolution of two different nearshore nourishments. A nearshore berm was constructed at Fort Myers Beach, Florida using mixed-sized sediment dredged from a nearby channel. The nearshore berm was placed in water depths between 1.2 and 2.4 m with the berm crest …

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Investigating Meter Scale Topographic Variation As A Factor Of Monterey Pine (Pinus Radiata) Growing Conditions At Kenneth Norris Rancho Marino Reserve, Cambria, Ca, William J. Meyst Jun 2014

Investigating Meter Scale Topographic Variation As A Factor Of Monterey Pine (Pinus Radiata) Growing Conditions At Kenneth Norris Rancho Marino Reserve, Cambria, Ca, William J. Meyst

Natural Resources Management and Environmental Sciences

Endemic Monterey pine (Pinus radiata) is limited to three locations in California due to its unique ecological requirements. This project was conducted to investigate spatial growth patterns ofMonterey pine over complex ground surfaces. The coastal hills of Rancho Marino Reserve, Cambria, were surveyed using four 150-m transects to quantify and record ground surface features and growing conditions ofMonterey pine. Changes in elevation of each transect were measured using an Abney level. Linear ground surfaces were found at 86% (344 of 400) of survey nodes. Convex ground surfaces were found at 10.5% of survey nodes (42 of 400). Of …

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The University Of Nebraska State Museum, Robert F. Diffendal Jr. Jun 2014

The University Of Nebraska State Museum, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

I first walked through the doors of Morrill Hall on the main or City Campus of the University of Nebraska on a day late in August of 1962 and thought that I had entered paleontology heaven. Morrill Hall then housed the University of Nebraska State Museum (UNSM). most of the Geology Department, and some other parts of university units. I was a new graduate student hoping to pursue research in invertebrate paleontology in the Department of Geology and was on my way to see the department chairman for the first time. When I entered the building I walked through a …

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Investigating Telogenetic Karst Aquifer Processes And Evolution In South-Central Kentucky, U.S., Using High-Resolution Storm Hydrology And Geochemistry Monitoring, Nicholas Lawhon May 2014

Investigating Telogenetic Karst Aquifer Processes And Evolution In South-Central Kentucky, U.S., Using High-Resolution Storm Hydrology And Geochemistry Monitoring, Nicholas Lawhon

Masters Theses & Specialist Projects

Recent studies have investigated the hydrological and geochemical characteristics of karst aquifers in different settings; however, telogenetic karst aquifer processes remain poorly understood. In south-central Kentucky, the iconic Lost River Cave and Valley represents a large, complex telogenetic karst drainage basin with a series of discharge points along a collapsed section of the cave. Two Campbell Scientific® CR1000 automated dataloggers were installed at Blue Hole Four, a primary discharge point of the Lost River Karst Aquifer (LRKA). These dataloggers recorded spring discharge, water temperature, specific conductance (SpC), and pH at ten-minute intervals from January to November, 2013. During the year, …

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Geologic Constraints And Speleogenesis Of Cova Des Pas De Vallgornera, A Complex Coastal Cave From Mallorca Island (Western Mediterranean), Joaquín Ginés, Joan J. Fornós, Angel Ginés, Antoni Merino, Francesc Gràcia May 2014

Geologic Constraints And Speleogenesis Of Cova Des Pas De Vallgornera, A Complex Coastal Cave From Mallorca Island (Western Mediterranean), Joaquín Ginés, Joan J. Fornós, Angel Ginés, Antoni Merino, Francesc Gràcia

International Journal of Speleology

The flat areas of eastern and southern Mallorca host a remarkable coastal karst, where Cova des Pas de Vallgornera stands out due to its length (more than 74 km) and its special morphological suite. The pattern of the cave is quite heterogeneous showing sharp differences produced by the architecture of the Upper Miocene reef: spongework mazes and collapse chambers dominate in the reef front facies, whereas joint-guided conduits are the rule in the back reef carbonates. Regarding the speleogenesis of the system, a complex situation is envisaged involving three main agents: coastal mixing dissolution, drainage of meteoric diffuse recharge, and …

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Cave Deposits And Sedimentary Processes In Cova Des Pas De Vallgornera (Mallorca, Western Mediterranean), Joan J. Fornós, Joaquin Ginés, Francesc Gràcia, Antoni Merino Juncadella, Lluís Gómez-Pujol, Pere Bover May 2014

Cave Deposits And Sedimentary Processes In Cova Des Pas De Vallgornera (Mallorca, Western Mediterranean), Joan J. Fornós, Joaquin Ginés, Francesc Gràcia, Antoni Merino Juncadella, Lluís Gómez-Pujol, Pere Bover

International Journal of Speleology

The Cova des Pas de Vallgornera is an important and protected coastal cave, located in the southern part of the island of Mallorca, that outstands due to its length and the complex processes involved in its speleogenesis. Although sediments are not the main topic of interest, their presence as well as their paleontological contents are valuable evidence for paleoclimatic and chronological reconstructions of the cave morphogenesis. The sedimentary infilling is characterized by a scarce presence of clastic sedimentation, mainly composed of silts and clays, which can only be found at some minor passages in the innermost parts of the cave. …

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Geology – Future Continent, Joy Wulke Feb 2014

Geology – Future Continent, Joy Wulke

The Transdisciplinary STEAM+ Journal

Terra Mirabila, a multi-media presentation illustrating the geological story of Stony Creek Granite back through complex sequence of geological events that spanned some 600 million years of early history.

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The West Tidewater Earthflow, Northern Oregon Coast Range, Barry A. Sanford Feb 2014

The West Tidewater Earthflow, Northern Oregon Coast Range, Barry A. Sanford

Dissertations and Theses

The West Tidewater earthflow, one of the largest in Oregon's history, occurred in December of 1994. The earthflow is located approximately 15 km north of Jewel, Oregon near the summit ofthe Northern Oregon Coast Range Mountains. The earthflow is 900 m long and 250 m wide, giving it a surface area of 9 ha, or 22 acres. Volume is 3.5 million m3. The earthflow occurred in low strength, well-bedded, tuffaceous, carbonaceous, micaceous, clay-rich mudstone, and very fine-grained, feldspathic, clay-rich siltstone of the lower Miocene age Northrup Creek Formation. The soil clay fractions contain up to 90% smectite with …

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Some Reflections On Our Experiences At Sun Yat-Sen University Since 1985, Robert F. Diffendal Jr., Anne P. Diffendal Jan 2014

Some Reflections On Our Experiences At Sun Yat-Sen University Since 1985, Robert F. Diffendal Jr., Anne P. Diffendal

Robert F. Diffendal, Jr., Publications

Professor Zhang Ke, Chairman of the Department of Earth Sciences at Sun Yat-sen University, has asked us to write about some of our memories from our several visits to Sun Yat-sen University, as part of the 2014 celebration of the 90th anniversary of the founding of the university and the creation of the department. We are very pleased to do so and to include with our written comments copies of some photographs that we have taken during these visits. We have gone back through our notes, books, tourist maps, photo files, and other information that we have kept as souvenirs …

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Slope Stability Analysis Of Mount Meager, South-Western British Columbia, Canada, Rachel M. Hetherington Jan 2014

Slope Stability Analysis Of Mount Meager, South-Western British Columbia, Canada, Rachel M. Hetherington

Dissertations, Master's Theses and Master's Reports - Open

The Mount Meager Volcanic Complex (MMVC) in south-western British Columbia is a potentially active, hydrothermally altered massif comprising a series of steep, glaciated peaks. Climatic conditions and glacial retreat has led to the further weathering, exposure and de-buttressing of steep slopes composed of weak, unconsolidated material. This has resulted in an increased frequency of landslide events over the past few decades, many of which have dammed the rivers bordering the Complex. The breach of these debris dams presents a risk of flooding to the downstream communities. Preliminary mapping showed there are numerous sites around the Complex where future failure could …

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Interpreting The Paleozoogeography And Sea Level History Of Thermally Anomalous Marine Terrace Faunas: A Case Study From The Last Interglacial Complex Of San Clemente Island, California, Daniel R. Muhs, Lindsey T. Groves, R. Randall Schumann Jan 2014

Interpreting The Paleozoogeography And Sea Level History Of Thermally Anomalous Marine Terrace Faunas: A Case Study From The Last Interglacial Complex Of San Clemente Island, California, Daniel R. Muhs, Lindsey T. Groves, R. Randall Schumann

United States Geological Survey: Publications

Marine invertebrate faunas with mixtures of extralimital southern and extralimital northern faunal elements, called thermally anomalous faunas, have been recognized for more than a century in the Quaternary marine terrace record of the Pacific Coast of North America. Although many mechanisms have been proposed to explain this phenomenon, no single explanation seems to be applicable to all localities where thermally anomalous faunas have been observed. Here, we describe one such thermally anomalous fossil fauna that was studied on the second emergent marine terrace at Eel Point on San Clemente Island. The Eel Point terrace complex is a composite feature, consisting …

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Identifying Sources Of Aeolian Mineral Dust: Present And Past, Daniel R. Muhs, Joseph M. Prospero, Matthew C. Baddock, Thomas E. Gill Jan 2014

Identifying Sources Of Aeolian Mineral Dust: Present And Past, Daniel R. Muhs, Joseph M. Prospero, Matthew C. Baddock, Thomas E. Gill

United States Geological Survey: Publications

Aeolian mineral dust is an important component of the Earth’s environmental systems, playing roles in the planetary radiation balance, as a source of fertilizer for biota in both terrestrial and marine realms and as an archive for understanding atmospheric circulation and paleoclimate in the geologic past. Crucial to understanding all of these roles of dust is the identification of dust sources. Here we review the methods used to identify dust sources active at present and in the past. Contemporary dust sources, produced by both glaciogenic and non-glaciogenic processes, can be readily identified by the use of Earth-orbiting satellites. These data …

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Coastal Geology And Recent Origins For Sand Point, Lake Superior, Timothy G. Fisher, David E. Krantz, Mario R. Castaneda, Walter L. Loope, Harry M. Jol, Ronald J. Goble, Melinda C. Higley, Samantha Dewald, Paul R. Hanson Jan 2014

Coastal Geology And Recent Origins For Sand Point, Lake Superior, Timothy G. Fisher, David E. Krantz, Mario R. Castaneda, Walter L. Loope, Harry M. Jol, Ronald J. Goble, Melinda C. Higley, Samantha Dewald, Paul R. Hanson

Department of Earth and Atmospheric Sciences: Faculty Publications

Sand Point is a small cuspate foreland located along the southeastern shore of Lake Superior within Pictured Rocks National Lakeshore near Munising, Michigan. Park managers’ concerns for the integrity of historic buildings at the northern periphery of the point during the rising lake levels in the mid-1980s greatly elevated the priority of research into the geomorphic history and age of Sand Point. To pursue this priority, we recovered sediment cores from four ponds on Sand Point, assessed subsurface stratigraphy onshore and offshore using geophysical techniques, and interpreted the chronology of events using radiocarbon and luminescence dating. Sand Point formed at …

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Nebraska Statewide Groundwater-Level Monitoring Report 2014, A. R. Young, M. E. Burbach, L. M. Howard Jan 2014

Nebraska Statewide Groundwater-Level Monitoring Report 2014, A. R. Young, M. E. Burbach, L. M. Howard

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Analysis Of Vesicular Porosity In Soils Using High-Resolution X-Ray Computed Tomograpy, Judith K. Turk, Robert C. Graham Jan 2014

Analysis Of Vesicular Porosity In Soils Using High-Resolution X-Ray Computed Tomograpy, Judith K. Turk, Robert C. Graham

Conservation and Survey Division: Faculty and Staff Publications

Vesicular horizons are common at the surface of arid and semiarid soils and play a critical role in regulating infiltration. Most methods for examining pore morphology in the vesicular horizon involve physical sectioning of the sample and individual measurement of pores, which is time-consuming and provides an incomplete view of the pores. The objectives of this study were to (i) develop methods for the classification and characterization of pores in the vesicular horizon using high resolution X-ray computed tomography (HRXCT) and (ii) use these methods to examine the distribution of pores within vesic-ular peds. Three intact peds were scanned by …

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The Groundwater Atlas Of Lancaster County, Dana Divine Jan 2014

The Groundwater Atlas Of Lancaster County, Dana Divine

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Determining Hillslope Diffusion Rates In A Boreal Forest: Quaternary Fluvial Terraces In The Nenana River Valley, Central Alaska Range, Laurel Anne Walker Jan 2014

Determining Hillslope Diffusion Rates In A Boreal Forest: Quaternary Fluvial Terraces In The Nenana River Valley, Central Alaska Range, Laurel Anne Walker

Theses and Dissertations--Earth and Environmental Sciences

The subarctic boreal forest biome is predicted to experience higher magnitudes of warming than other biomes due to climate change. The effects of this warming will be pronounced in areas underlain by discontinuous permafrost where melting permafrost and distinct changes in vegetation patterns are expected. To better understand rates of hillslope diffusion in the boreal forest I have used a geomorphic process modeling approach, using data from a sequence of Quaternary fluvial terraces located in the Nenana River valley of central Alaska. I hypothesized that diffusion rates here would be slower when compared to the mid-latitudes, and faster on north …

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Paleoseismic And Structural Characterization Of The Hines Creek Fault: Denali National Park And Preserve, Alaska, Sara E. Federschmidt Jan 2014

Paleoseismic And Structural Characterization Of The Hines Creek Fault: Denali National Park And Preserve, Alaska, Sara E. Federschmidt

Theses and Dissertations--Earth and Environmental Sciences

The Hines Creek fault (HCF) is a Holocene-active fault in central Alaska. Its trace has been mapped several times, but data on the history of fault displacement is scarce. As a major crustal-scale geologic boundary with uncertain Quaternary tectonic activity, it is a priority for more to be known about the activity of this fault to better understand the hazards it presents to the Denali National Park and Preserve and Alaskan infrastructure. This study characterizes the late Quaternary activity of the HCF through surficial geologic mapping and paleoseismic investigations. Mapping revealed a very steep (~84°-88° apparent dip), north dipping fault …

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Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu Jan 2014

Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu

Department of Earth, Environment and Sustainability Faculty Publications

Reconstruction of the Hirnantian (Late Ordovician) palaeotopography in South China is important for understanding the distribution pattern of the Hirnantian marine depositional environment. In this study, we reconstructed the Hirnantian palaeotopography in the Upper Yangtze region based on the rankings of the palaeo-water depths, which were inferred according to the lithofacies and biofacies characteristics of the sections. Data from 374 Hirnantian sections were collected and standardized through the online Geobiodiversity Database. The Ordinary Kriging interpolation method in the ArcGIS software was applied to create the continuous surface of the palaeo-water depths, i.e. the Hirnantian palaeotopography. Meanwhile, the line transect analysis …

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A Remote Sensing Investigation Of Elevated Sub-Horizontal Topographic Surfaces In The Wichita Mountains, Oklahoma, Liang Xue Jan 2014

A Remote Sensing Investigation Of Elevated Sub-Horizontal Topographic Surfaces In The Wichita Mountains, Oklahoma, Liang Xue

Masters Theses

"Multiple elevated horizontal to sub-horizontal topographic surfaces are present in the Wichita Mountains, Oklahoma. Elevated topographic surfaces, developed primarily on granite bedrock with gentle slopes of 0.5 to 7⁰,were investigated using 1) Digital Elevation Models (DEMs) extracted from NAD 27 UTM coordinates, 2) Google Earth imagery, and 3) USGS topographic maps. In the western Wichita Mountains prominent topographic surfaces at elevations of 720 ± 5 m, 685 ± 5 m, and 660 ± 5 m are well preserved on at least four different mountains (e.g., Solder's Peak, King Mt.) and can be correlated with similar surfaces on at least seven …

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Architecture, Heterogeneity, And Origin Of Late Miocene Fluvial Deposits Hosting The Most Important Aquifer In The Great Plains, Usa, R. Matthew Joeckel, Steve R. Wooden Jr., Jesse T. Korus, Jon Garbisch Jan 2014

Architecture, Heterogeneity, And Origin Of Late Miocene Fluvial Deposits Hosting The Most Important Aquifer In The Great Plains, Usa, R. Matthew Joeckel, Steve R. Wooden Jr., Jesse T. Korus, Jon Garbisch

Department of Earth and Atmospheric Sciences: Faculty Publications

The Ash Hollow Formation (AHF) of the Ogallala Group is an important sedimentary archive of the emergence of the Great Plains and it contains major groundwater resources. Stratal patterns of constituent alluvial lithofacies demonstrate that the AHF is much more heterogeneous than is commonly assumed. Very fine- to fine-grained sandstone dominate overall, chiefly lithofacies Sm (massive to locally stratified sandstone). Stacked, thin sheets of Sm with accretionary macroform surfaces are common, indicating that many sandstone architectural elements originated as compound-bar deposits in dominantly sand-bed streams. Channel forms are difficult to identify and steep cutbanks are absent. Multiple units of lithofacies …

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Ashfall Tephra In The Ogallala Group Of The Great Plains: Characteristics And Significance, Michael E. Perkins, Robert F. Diffendal Jr., Michael R. Voorhies, Barbara P. Nash, Bruce E. Bailey Jan 2014

Ashfall Tephra In The Ogallala Group Of The Great Plains: Characteristics And Significance, Michael E. Perkins, Robert F. Diffendal Jr., Michael R. Voorhies, Barbara P. Nash, Bruce E. Bailey

Robert F. Diffendal, Jr., Publications

The Miocene Ogallala Group blankets the Great Plains east of the Rocky Mountains. This sheet of largely fluvial deposits, lying downwind of major silicic volcanic fields to the west, was ideally located to receive and preserve tephra from these fields. This investigation brings modern methods of tephrochronlogy to bear on the age and identity of Ogallala tephra. Results indicate that ~40 separate tephra layers, ranging in age from ~16.5–5.0 Ma, in the Ogallala. Most tephra came from Yellowstone hotspot sources. The relative frequency of hotspot tephra in the Ogallala matches that in more proximal regions to the west with peak …

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Study Of Filled Dolines By Using 3d Stereo Image Processing And Electrical Resistivity Imaging, Mateja Breg Valjavec Jan 2014

Study Of Filled Dolines By Using 3d Stereo Image Processing And Electrical Resistivity Imaging, Mateja Breg Valjavec

International Journal of Speleology

This article deals with doline degradation due to uncontrolled waste dumping in the past in the Logatec Polje in Slovenia. It introduces a concept for determining 3D geometric characteristics (shape, depth, radius, area, and volume) of formerly concave landforms (i.e., recently filled dolines) by using a combination of two methods: (1) photogrammetric stereo processing of archival aerial photographs and (2) electrical resistivity imaging (ERI). To represent, visualize, and study the characteristics of the former surface morphology (i.e., the dolines before they were filled), a digital terrain model (DTM) for 1972 (DTM1972) was made using digital photogrammetry processing of five sequential …

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Upper Pleistocene And Holocene Palaeoenvironmental Records In Cueva Mayor Karst (Atapuerca, Spain) From Different Proxies: Speleothem Crystal Fabrics, Palynology And Archaeology., Virginia Martínez-Pillado, Arantza Aranburu, Juan Luis Arsuaga, Blanca Ruiz-Zapata, Maria José Gil-García, Heather Stoll, Iñaki Yusta, Eneko Iriarte, José Miguel Carretero, R. Lawrence Edwards, Hai Cheng Jan 2014

Upper Pleistocene And Holocene Palaeoenvironmental Records In Cueva Mayor Karst (Atapuerca, Spain) From Different Proxies: Speleothem Crystal Fabrics, Palynology And Archaeology., Virginia Martínez-Pillado, Arantza Aranburu, Juan Luis Arsuaga, Blanca Ruiz-Zapata, Maria José Gil-García, Heather Stoll, Iñaki Yusta, Eneko Iriarte, José Miguel Carretero, R. Lawrence Edwards, Hai Cheng

International Journal of Speleology

The Cueva Mayor karst system of Atapuerca, in Northern Spain, hosts a highly significant record of human occupation from the Pleistocene. The climatic context of the human activities during the Pleistocene-Holocene for this inland site has not been well constrained, since existing records of the palaeoclimatic evolution of the Northern Iberian Peninsula are from more distal coastal and high-elevation sites. In this study, we interpret the palaeoenvironmental information recorded on the petrography of a stalagmite and the pollen spectra of the Sierra de Atapuerca karst system during the last 20 kyr. The integration of both types of records has allowed …

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