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Articles 361 - 390 of 491

Full-Text Articles in Geology

Sedimentation Patterns In A Stabilized Migratory Inlet, Blind Pass, Florida, Ping Wang, David K. Tidwell, Tanya Beck, Nicholas C. Kraus Jan 2007

Sedimentation Patterns In A Stabilized Migratory Inlet, Blind Pass, Florida, Ping Wang, David K. Tidwell, Tanya Beck, Nicholas C. Kraus

Geology Faculty Publications

The shoaling rate in Blind Pass entrance channel approximately equals the net southward longshore sediment transport rate. Most of the shoaling occurs along the northern side of the channel. Flow measurements and numerical modeling reveal that the ebb current is approximately twice as strong in the thalweg along the south side as compared to the rest of the channel. In contrast, the flood current is mainly uniform across the inlet and is stronger than the ebb flow over the northern portion. This flow-velocity distribution induced by a nearly 90-deg bend of the channel contributes to the shoaling pattern. Two years …

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Data Report: Laboratory Testing Of Longshore Sand Transport By Waves And Currents; Morphology Change Behind Headland Structures, Mark B. Gravens, Ping Wang Jan 2007

Data Report: Laboratory Testing Of Longshore Sand Transport By Waves And Currents; Morphology Change Behind Headland Structures, Mark B. Gravens, Ping Wang

Geology Faculty Publications

Data from five series of movable bed laboratory experiments are presented herein. These experiments were conducted in the Largescale Sediment Transport Facility at the U.S. Army Engineer Research and Development Center, Vicksburg, MS. The data collected from these experiments are being used to improve longshore sand transport relationships under the combined influence of waves and currents and the enhancement of predictive numerical models of beach morphology evolution, in particular, with respect to modeling of tombolo development at detached breakwates and T-groins. These data were instrumental in the development and validation of GENESIS-T (Hanson et al. 2006) an enhanced version of …

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A Taxonomic Survey Of Lamp Flora (Algae And Cyanobacteria) In Electrically Lit Passages Within Mammoth Cave National Park, Kentucky, Thomas Smith, Rick Olson Jan 2007

A Taxonomic Survey Of Lamp Flora (Algae And Cyanobacteria) In Electrically Lit Passages Within Mammoth Cave National Park, Kentucky, Thomas Smith, Rick Olson

International Journal of Speleology

A taxonomic survey of the lamp flora from electrically lit passages in Mammoth Cave, Mammoth Cave National Park, identified 28 species. Overall, cyanobacteria were dominant represented by 14 species (50% of the total), green algae had eight species (29%), and six diatoms species (21%) were present. There was not a correlation between species diversity and temperature, but there is a general trend of increasing diversity with warmer temperatures. There were two algal or cyanobacterial species identified in this study that overlapped with previous studies. There is a lack of continuity between previous studies only having one species identified in more …

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The Polygenetic Caves Of Cuatro Ciénegas (Coahuila, Mexico): Morphology And Speleogenesis, Leonardo Piccini, Paolo Forti, Italo Giulivo, Marco Mecchia Jan 2007

The Polygenetic Caves Of Cuatro Ciénegas (Coahuila, Mexico): Morphology And Speleogenesis, Leonardo Piccini, Paolo Forti, Italo Giulivo, Marco Mecchia

International Journal of Speleology

The Cuatro Ciénegas area is renown worldwide for its thermal springs, which feed a unique ecosystem consisting of many pools, lakes and marshes. The pools also represent a very important water resource in a region characterized by scarce rainfalls. Field investigation has emphasized the role of karst in the hydrogeology of the area. Only few and restricted forms of surface karst are represented; caves are mainly relics of old speleogenetic phases of thermal and bathyphreatic water flow.

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Speleothems As Indicators Of Wet And Dry Periods, Ian John Fairchild, Emily Anne Mcmillan Jan 2007

Speleothems As Indicators Of Wet And Dry Periods, Ian John Fairchild, Emily Anne Mcmillan

International Journal of Speleology

Calcareous speleothems provide a record of dripwater composition which in turn is a function of climatic conditions. The historical focus of speleothem palaeoclimate studies has been on the derivation of palaeotemperatures through oxygen isotope studies. However, it is now realized that water availability is a more generally important control on their characteristics. Growth rate and growth morphology in principle should give rise to recognizable changes at low flow. However, accidental plumbing effects during aquifer evolution, can also lead to variations in water supply and it is not easy to distinguish these effects. In areas where there is a strong amount …

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Climatic Differences And Similarities Between Indian And East Asian Monsoon Regions Of China Over The Last Millennium: A Perspective Based Mainly On Stalagmite Records, Ming Tan Jan 2007

Climatic Differences And Similarities Between Indian And East Asian Monsoon Regions Of China Over The Last Millennium: A Perspective Based Mainly On Stalagmite Records, Ming Tan

International Journal of Speleology

Cave sediments, especially stalagmites, have been providing absolute dated climate records that can extend from the present to over 500,000 years ago. Based on the reconstructed temperature time series, a comprehensive overview of the climatic differences and similarities between the Indian and the East Asian Monsoon regions of China over the last millennium is presented. Evidence from accurately dated and high-resolution records including stalagmites, ice cores and tree rings show that there was a “Medieval Warm Period” (around 1000 to 1400 AD) in north and east China where climate is dominated by the East Asian monsoon; whilst no such interval …

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The Impact Of Host Rock Geochemistry On Bacterial Community Structure In Oligotrophic Cave Environments, Hazel A. Barton, Nicholas M. Taylor, Michael P. Kreate, Austin C. Springer, Stuart A. Oehrle, Janet L. Bertog Jan 2007

The Impact Of Host Rock Geochemistry On Bacterial Community Structure In Oligotrophic Cave Environments, Hazel A. Barton, Nicholas M. Taylor, Michael P. Kreate, Austin C. Springer, Stuart A. Oehrle, Janet L. Bertog

International Journal of Speleology

Despite extremely starved conditions, caves contain surprisingly diverse microbial communities. Our research is geared toward understanding what ecosystems drivers are responsible for this high diversity. To asses the effect of rock fabric and mineralogy, we carried out a comparative geomicrobiology study within Carlsbad Cavern, New Mexico, USA. Samples were collected from two different geologic locations within the cave: WF1 in the Massive Member of the Capitan Formation and sF88 in the calcareous siltstones of the Yates Formation. We examined the organic content at each location using liquid chromatography mass spectroscopy and analyzed microbial community structure using molecular phylogenetic analyses. In …

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Petrographic And Geochemical Study On Cave Pearls From Kanaan Cave (Lebanon), Fadi H. Nader Jan 2007

Petrographic And Geochemical Study On Cave Pearls From Kanaan Cave (Lebanon), Fadi H. Nader

International Journal of Speleology

The Kanaan cave is situated at the coastal zone, north of Beirut City (capital of Lebanon). The cave is located within the upper part of the Jurassic Kesrouane Formation (Liassic to Oxfordian) which consists mainly of micritic limestone. Twenty seven cave pearls were subjected to petrographic (conventional and scanning electron microscopy) and geochemical analyses (major/trace elements and stable isotopes). The cave pearls were found in an agitated splash-pool with low mud content. They are believed to have formed through chemical precipitation of calcite in water over-saturated with calcium. The nucleus and micritic laminae show δ18OV-PDB values of …

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Seasonal Variations Of Co2 And 222Rn In A Mediterranean Sinkhole - Spring (Causse D’Aumelas, Se France), Christelle Batiot-Guilhe, Jean-Luc Seidel, Hervé Jourde, Olivier Hébrard, Vincent Bailly-Comte Jan 2007

Seasonal Variations Of Co2 And 222Rn In A Mediterranean Sinkhole - Spring (Causse D’Aumelas, Se France), Christelle Batiot-Guilhe, Jean-Luc Seidel, Hervé Jourde, Olivier Hébrard, Vincent Bailly-Comte

International Journal of Speleology

Carbon dioxide and 222Rn monitoring of the atmosphere of a Mediterranean sink hole - spring (SE France) during two hydrological cycles (from September 2004 to September 2006) showed seasonal variations with very high concentrations during summer (greater than 6% and 20 000 Bq/m3, respectively). Gas dynamics in caves often show seasonal variations. Meteorological parameters (barometric pressure and temperature mainly), cave geometry and fracture networks control exchanges between the cavity and outside atmosphere. Carbon dioxide and 222Rn may have different sources (atmosphere, soil, bedrock, deep gas diffusion, in situ oxidation of organic matter and, in some caves, …

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Eogenetic Karst, Glacioeustatic Cave Pools And Anchialine Environments On Mallorca Island: A Discussion Of Coastal Speleogenesis, Angel Ginés, Joaquín Ginés Jan 2007

Eogenetic Karst, Glacioeustatic Cave Pools And Anchialine Environments On Mallorca Island: A Discussion Of Coastal Speleogenesis, Angel Ginés, Joaquín Ginés

International Journal of Speleology

Coastal karst is characterized by special geomorphologic and hydrodynamic conditions as well as by peculiar sedimentary, geochemical, and biospeleological environments. Generally, the more distinctive karstic features produced near the coastline are strongly influenced by sea-level changes, which generate a broad set of interactions between littoral processes and karst development. The glacioeustatic rises and falls of sea level affected the littoral karst in different ways, namely: vertical and horizontal shifts in the shoreline position, changes in elevation of the local water table, and vertical displacements of the halocline. Most eogenetic karsts have been subjected over long time spans to repeated changes …

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Sails: A New Gypsum Speleothem From Naica, Chihuahua, Mexico, Tullio Bernabei, Paolo Forti, Roberto Villasuso Jan 2007

Sails: A New Gypsum Speleothem From Naica, Chihuahua, Mexico, Tullio Bernabei, Paolo Forti, Roberto Villasuso

International Journal of Speleology

The caves of Naica (Chihuahua, Mexico) are perhaps the most famous mine caves of the world due to the presence of gigantic gypsum crystals. Nevertheless, very little research has been carried out on this karst area until now. A multidisciplinary investigation started in 2006 with the aim not only to define the genesis and the age of the Naica gypsum crystals, but also on other scientific aspects of these caves. This paper describes a completely new type of gypsum speleothem: the “sails”, observed only inside the Cueva de las Velas, one of the caves of the Naica system. This speleothem …

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Acadian Biospeleology: Composition And Ecology Of Cave Fauna Of Nova Scotia And Southern New Brunswick, Canada, Max Moseley Jan 2007

Acadian Biospeleology: Composition And Ecology Of Cave Fauna Of Nova Scotia And Southern New Brunswick, Canada, Max Moseley

International Journal of Speleology

The vertebrate and invertebrate fauna, environment and habitats of caves and disused mines in Nova Scotia and southern New Brunswick are provisionally catalogued and described, based on field collections made over many years. The area was glaciated and the subterranean fauna consists of non-troglobites all of which have arrived and colonised the caves during or following final recession of the Pleistocene glaciers. The statistical composition of the fauna at the higher taxonomic level is similar to that in Ontario, but is less species rich and there are some notable ecological and other differences. Porcupine dung accumulations are an important habitat …

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Bomb-Spike Dating Of A Mummified Baboon In Ludwig Cave, Namibia, Greg Hodgins, George A. Brook, Eugene Marais Jan 2007

Bomb-Spike Dating Of A Mummified Baboon In Ludwig Cave, Namibia, Greg Hodgins, George A. Brook, Eugene Marais

International Journal of Speleology

In 1982 a mummified adult female baboon was discovered on a ledge in Ludwig Cave in Namibia. A toe bone was removed for dating in July 1995. AMS radiocarbon dating of bone collagen, tendon, and skin indicates a post-modern age. Application of the atomic bomb-spike calibration curve suggests death in late 1977 and an age at death of around 19 years. Baboons roost in the cave and the mummified female, along with a mummified juvenile male discovered in 2002 and three rotting corpses discovered in 1995, were probably chased by other baboons or by leopards down a ca. 6 m …

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Sinkhole Structure Imaging In Covered Karst Terrain, Sarah E. Kruse, M. Grasmueck, Matthew Weiss, D. Viggiano Aug 2006

Sinkhole Structure Imaging In Covered Karst Terrain, Sarah E. Kruse, M. Grasmueck, Matthew Weiss, D. Viggiano

Geology Faculty Publications

Ground penetrating radar (GPR) and resistivity techniques have been widely used to map the locations of sinkholes in covered karst terrain. To determine whether a sinkhole is a likely preferential conduit for groundwater flow, however, requires higher-resolution imaging than that used in conventional sinkhole mapping surveys. Field observations combined with simulated surveys for a 15-m diameter 3-m deep sinkhole in west-central Florida are used to assess the resolution of GPR and resistivity surveys targeting the semiconfining unit that floors the sinkhole depression. 2D resistivity surveys clearly show the central depression as well as resistivity contrasts between the cover sediments within …

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Geophysical Investigations And Groundwater Modeling Of The Hydrologic Conditions At Masaya Caldera, Nicaragua, Richard Eric Macneil Jul 2006

Geophysical Investigations And Groundwater Modeling Of The Hydrologic Conditions At Masaya Caldera, Nicaragua, Richard Eric Macneil

USF Tampa Graduate Theses and Dissertations

Masaya volcano, Nicaragua, has been the site of tremendous Plinian basaltic eruptions. Two eruptions ~6,500 and 2,250 BP formed the 6 kilometer (km) x 11 km, northwest trending Masaya caldera. The present day active Santiago Crater within the caldera is the site of persistent volcano degassing and occasional phreatic explosions. While the mechanism responsible for these phreatic explosions is unclear, one possible explanation is the interaction of groundwater with the shallow magma chamber beneath Masaya. This interaction with meteoric water is supported by the substantial steam discharge from the vent, which is significantly larger than other similar volcanoes in the …

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Evaluation Of Geophysical And Thermal Methods For Detecting Submarine Groundwater Discharge (Sgd) In The Suwannee River Estuary, Florida, Matthew Weiss Mar 2006

Evaluation Of Geophysical And Thermal Methods For Detecting Submarine Groundwater Discharge (Sgd) In The Suwannee River Estuary, Florida, Matthew Weiss

USF Tampa Graduate Theses and Dissertations

Submarine groundwater discharge (SGD) represents a significant portion of the total discharge from coastal aquifers through diffuse seepage and point source springs, but can be difficult to locate. SGD is important as it can be a source of nutrients to estuaries and other coastal ecosystems. In an effort to evaluate geophysical and thermal methods for detecting SGD on the Florida Gulf coast, a suite of water-borne surveys were run in conjunction with aerial thermal imagery over the lower Suwannee River and estuary in March and September 2005. Thermal imagery exploits temperature differences between discharging groundwater and surface water. Thermal images …

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Unconfined Versus Confined Speleogenetic Settings: Variations Of Solution Porosity, Alexander Klimchouk Jan 2006

Unconfined Versus Confined Speleogenetic Settings: Variations Of Solution Porosity, Alexander Klimchouk

International Journal of Speleology

Speleogenesis in confined settings generates cave morphologies that differ much from those formed in unconfined settings. Caves developed in unconfined settings are characterised by broadly dendritic patterns of channels due to highly competing development. In contrast, caves originated under confined conditions tend to form two- or three-dimensional mazes with densely packed conduits. This paper illustrates variations of solution (channel) porosity resulted from speleogenesis in unconfined and confined settings by the analysis of morphometric parameters of typical cave patterns. Two samples of typical cave systems formed in the respective settings are compared. The sample that represents unconfined speleogenesis consists of solely …

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Relationships Between Deflector Faults, Collapse Dolines And Collector Channel Formation: Some Examples From Slovenia, France Šušteršič Jan 2006

Relationships Between Deflector Faults, Collapse Dolines And Collector Channel Formation: Some Examples From Slovenia, France Šušteršič

International Journal of Speleology

In some Slovenian caves collector channels gather sinking underground streams and redirect them for potentially long distances parallel to certain faults. The collector channels formed due to ongoing long-term collapse of cave roofs at the points where passages break through the faults, which function as a kind of screen and are termed deflector faults. The fault trends are marked by collapse within the caves, and by active collapse dolines at the surface.

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Salt Ingestion Caves, Charles A. Lundquist, William W. Varnedoe Jr. Jan 2006

Salt Ingestion Caves, Charles A. Lundquist, William W. Varnedoe Jr.

International Journal of Speleology

Large vertebrate herbivores, when they find a salt-bearing layer of rock, say in a cliff face, can produce sizable voids where, over generations, they have removed and consumed salty rock. The cavities formed by this natural animal process constitute a unique class of caves that can be called salt ingestion caves. Several examples of such caves are described in various publications. An example in Mississippi U.S.A., Rock House Cave, was visited by the authors in 2000. It seems to have been formed by deer or bison. Perhaps the most spectacular example is Kitum Cave in Kenya. This cave has been …

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Tracer-Test Design For Losing Stream–Aquifer Systems, Malcolm S. Field Jan 2006

Tracer-Test Design For Losing Stream–Aquifer Systems, Malcolm S. Field

International Journal of Speleology

Hydrological tracer testing is an effective way for assessing the significance and extent of leakage through the bed of an influent (losing and sinking) stream. In karstic terranes, leakage from losing and sinking streams typically resurge at downstream springs, but flow may be intercepted by production wells. Although sinking streams that disappear into swallow holes and caves are relatively easy to trace, developing a tracer test design for a losing stream that allows slow percolation through its bed is complicated by the lack of basic knowledge regarding leakage rate, leakage locations along its length, and temporal variability. To overcome these …

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Caves And Speleogenesis At Blomstrandsøya, Kongsfjord, W. Spitsbergen, Stein-Erik Lauritzen Jan 2006

Caves And Speleogenesis At Blomstrandsøya, Kongsfjord, W. Spitsbergen, Stein-Erik Lauritzen

International Journal of Speleology

Blomstrandsøya, at Kongsfjord (78° 57’N), Spitsbergen, is within the high arctic, a completely permafrozen zone. The bedrock consists of Paleozoic marbles and has yielded a surprising amount of karst features. Early phases of hydrothermal, possibly Caledonian, speleogenesis and subsequent Devonian karstification with redbed deposits is well documented. 62 active seacaves, and more than 30 relict karst caves were found in the coastal cliffs and in escarpment faces around the island. All caves have very limited extent; they are either quite short, like most of the active sea caves, or they are soon choked by frozen sediments and ground ice after …

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Thermal Variations In The Hyporheic Zone Of A Karst Stream, Toby Dogwiler, Carol Wicks Jan 2006

Thermal Variations In The Hyporheic Zone Of A Karst Stream, Toby Dogwiler, Carol Wicks

International Journal of Speleology

This investigation quantifies how temperatures in the streambed sediments of a karst stream fluctuate in relation to discharge, seasonal, and diurnal temperature variations as the stream passes through a karst window. Furthermore, the linkages between meteorological processes and temperature variation in the hyporheic zone are delineated. Examination of a high-resolution, three dimensional record of temperature variation in a karst stream substrate provides insight into thermal disturbances in the hyporheic zone. Temperatures in the upper portion of the hyporheic zone are strongly linked to air temperatures via the surface water. The variation is considerably less as depth increases. The annual temperature …

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Vashegyite From Gaura Cu Muscă Cave (Locvei Mountains, Romania): A New And Rare Phosphate Occurrence, Bogdan P. Onac, Luminiţa Zaharia, Joe Kearns, Daniel Veres Jan 2006

Vashegyite From Gaura Cu Muscă Cave (Locvei Mountains, Romania): A New And Rare Phosphate Occurrence, Bogdan P. Onac, Luminiţa Zaharia, Joe Kearns, Daniel Veres

International Journal of Speleology

This study investigated the occurrence of vashegyite from a guano-rich deposit located in the Gaura cu Muscă Cave, Romania. Analytical methods used include optical microscopy, X-ray powder diffraction (XRD), scanning electron-microscopy (SEM), inductively coupled plasma-atomic emission spectrometry (ICP-AES), thermal investigations and Fourier-transform infrared (FT-IR) analyses. Vashegyite occurs as friable, chalky white, irregular nodules of up to 2.5 cm in diameter, within a 15 cm thick sequence of organic and minerogenic sediments. The chemical structural formula is: (Al10.91Fe3+0.06Na0.1Ca0.02Mg0.08)Σ=11.17[(PO4)8.78(SiO4)0.056]Σ=8.83(OH) …

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The Distribution Of Diatom Flora In Ice Caves Of The Northern Yukon Territory, Canada: Relationship To Air Circulation And Freezing, Bernard Lauriol, Clément Prévost, Denis Lacelle Jan 2006

The Distribution Of Diatom Flora In Ice Caves Of The Northern Yukon Territory, Canada: Relationship To Air Circulation And Freezing, Bernard Lauriol, Clément Prévost, Denis Lacelle

International Journal of Speleology

In the late 1980’s and early 1990’s, various media in karst environments in the Northern Yukon Territory were examined for their diatom content. Cryogenic cave calcite powders, grus and various ice formations (ice plugs, ice stalagmites and floor ice) were collected from three freezing caves and one slope cave to make an inventory of the diatom content, and to explain the spatial distribution of the diatoms within the caves. The results show that approximately 20% of diatoms in the caves originate from external biotopes and habitats (e.g., river, lake, stream), with the remaining 80% of local origin (i.e., from subaerial …

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Studies Of Condensation/Evaporation Processes In The Glowworm Cave, New Zealand, C. R. De Freitas, A. Schmekal Jan 2006

Studies Of Condensation/Evaporation Processes In The Glowworm Cave, New Zealand, C. R. De Freitas, A. Schmekal

International Journal of Speleology

The condensation/evaporation process is important in caves, especially in tourist caves where there is carbon dioxide enriched air caused by visitors. The cycle of condensation and evaporation of condensate is believed to enhance condensation corrosion. The problem is condensation is difficult to measure. This study addresses the problem and reports on a method for measuring and modelling condensation rates in a limestone cave. Electronic sensors for measuring condensation and evaporation of the condensate as part of a single continuous process of water vapour flux are tested and used to collect 12 months of data. The study site is the Glowworm …

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Radon In Caves: Clinical Aspects, Stephen A. Craven, Berend J. Smit Jan 2006

Radon In Caves: Clinical Aspects, Stephen A. Craven, Berend J. Smit

International Journal of Speleology

Historical, experimental and clinical evidence is presented to suggest that radon constitutes a relatively small carcinogenic risk for casual visitors to caves. The risk is dependent on radon levels and the smoking of tobacco. Show cave guides, chronically exposed to radon, may be at increased risk for lung cancer due to the effects of radon, especially if they are smokers of tobacco.

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Identification Of Cave Minerals By Raman Spectroscopy: New Technology For Non-Destructive Analysis, William B. White Jan 2006

Identification Of Cave Minerals By Raman Spectroscopy: New Technology For Non-Destructive Analysis, William B. White

International Journal of Speleology

The identification of minerals from caves generally requires that samples be removed from the cave for analysis in the laboratory. The usual tools are X-ray powder diffraction, the optical microscope, and the scanning electron microscope. X-ray diffraction gives a definitive fingerprint by which the mineral can be identified by comparison with a catalog of reference patterns. However, samples must be ground to powder and unstable hydrated minerals may decompose before analysis is complete. Raman spectroscopy also provides a fingerprint useful for mineral identification but with the additional advantage that some a-priori interpretation of the spectra is possible (distinguishing carbonates from …

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Spectral Analysis Of Ground Penetrating Radar Response To Thin Sedimentary Layers, Swagata Guha, Sarah E. Kruse, E. E. Wright, U. E. Kruse Dec 2005

Spectral Analysis Of Ground Penetrating Radar Response To Thin Sedimentary Layers, Swagata Guha, Sarah E. Kruse, E. E. Wright, U. E. Kruse

Geology Faculty Publications

Ground penetrating radar (GPR) systems utilized in studies of sedimentary deposits generate wavelengths (tens of centimeters) that are commonly much longer than the thickness of bedding (often millimeters to centimeters) within the target strata. Where this is the case, radar profiles represent interference patterns. Simple models of radar response to sequences of thin beds such as those found in coastal deposits show potentially detectable spectral shifts toward higher frequencies in radar returns. Spectral analysis of radar data over barrier beach deposits at Waites Island, South Carolina, shows that returns from packages with heavy mineral laminations are shifted toward higher frequencies …

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Modeling Tephra Sedimentation From A Ruapehu Weak Plume Eruption, Costanza Bonadonna, J. C. Phillips, B. F. Houghton Aug 2005

Modeling Tephra Sedimentation From A Ruapehu Weak Plume Eruption, Costanza Bonadonna, J. C. Phillips, B. F. Houghton

Geology Faculty Publications

We present a two-dimensional model for sedimentation of well-mixed weak plumes, accounting for lateral spreading of the cloud, downwind advection, increase of volumetric flux in the rising stage, and particle transport during fallout. The 17 June 1996 subplinian eruption of Ruapehu produced a bent-over plume that rose to a height of 8.5 km in a wind field with an average velocity of 24 m s−1 and generated a narrow deposit on land extending up to 200 km from vent. The sedimentation from the Ruapehu plume was dominated by coarse ash, with all the blocks and most of the lapilli …

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Geochemistry Of Serpentinized Peridotites From The Mariana Forearc Conical Seamount, Odp Leg 125: Implications For The Elemental Recycling At Subduction Zones, Ivan P. Savov, Jeffrey G. Ryan, Massimo D'Antonio, Katherine Kelley, Patrick Mattie Apr 2005

Geochemistry Of Serpentinized Peridotites From The Mariana Forearc Conical Seamount, Odp Leg 125: Implications For The Elemental Recycling At Subduction Zones, Ivan P. Savov, Jeffrey G. Ryan, Massimo D'Antonio, Katherine Kelley, Patrick Mattie

Geology Faculty Publications

Recent examinations of the chemical fluxes through convergent plate margins suggest the existence of significant mass imbalances for many key species: only 20–30% of the to-the-trench inventory of large-ion lithophile elements (LILE) can be accounted for by the magmatic outputs of volcanic arcs. Active serpentinite mud volcanism in the shallow forearc region of the Mariana convergent margin presents a unique opportunity to study a new outflux: the products of shallow-level exchanges between the upper mantle and slab-derived fluids. ODP Leg 125 recovered serpentinized harzburgites and dunites from three sites on the crests and flanks of the active Conical Seamount. These …

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