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2001

Earth Sciences

University of South Florida

Articles 1 - 10 of 10

Full-Text Articles in Physical Sciences and Mathematics

Development Of A Large-Scale Laboratory Facility For Sediment Transport Research, David G. Hamilton, Bruce A. Ebersole, Ernest R. Smith, Ping Wang Sep 2001

Development Of A Large-Scale Laboratory Facility For Sediment Transport Research, David G. Hamilton, Bruce A. Ebersole, Ernest R. Smith, Ping Wang

Geology Faculty Publications

No abstract provided.

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Influence Of The Earthquake Cycle And Lithospheric Rheology On The Dynamics Of The Eastern California Shear Ζone, R. Malservisi, K. Furlong, Timothy H. Dixon Jul 2001

Influence Of The Earthquake Cycle And Lithospheric Rheology On The Dynamics Of The Eastern California Shear Ζone, R. Malservisi, K. Furlong, Timothy H. Dixon

School of Geosciences Faculty and Staff Publications

The Eastern California Shear Zone is bounded by the high heat flow region of the Basin and Range province and the low heat flow region of the Sierra Nevada block. This difference in thermal state influences the rheology of the lower crust/upper mantle, resulting in a viscosity contrast between the two regions. We analyze the effect of such a contrast on the kinematics and dynamics of the shear zone with numerical models. This viscosity contrast drives asymmetric strain accumulation in the upper crust, producing an asymmetric surface velocity field. An additional consequence of this strain pattern is the potential for …

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Refined Kinematics Of The Eastern California Shear Zone From Gps Observations, 1993-1998, M. Meghan Miller, Daniel J. Johnson, Timothy H. Dixon, Roy K. Dokka Feb 2001

Refined Kinematics Of The Eastern California Shear Zone From Gps Observations, 1993-1998, M. Meghan Miller, Daniel J. Johnson, Timothy H. Dixon, Roy K. Dokka

School of Geosciences Faculty and Staff Publications

Global Positioning System (GPS) results from networks spanning the Eastern California shear zone and adjacent Sierra Nevada block, occupied annually between 1993 and 1998, constrain plate margin kinematics. We use an elastic block model to relate GPS station velocities to long-term fault slip rate estimates. The model accounts for elastic strain accumulation on the San Andreas fault, as well as faults of the Eastern California shear zone. South of the Garlock fault, 14 mm/yr of dextral shear is distributed across the Eastern California shear zone. Some of this slip penetrates eastward into the Basin and Range, and a collective budget …

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Biogenic Speleothems: An Overview, Paolo Forti Jan 2001

Biogenic Speleothems: An Overview, Paolo Forti

International Journal of Speleology

The idea that speleothems may be somehow influenced by living organisms is rather old, but specific studies have only started in the last few decades and presently there are only a couple of systematic papers on this topic. The role of micro-organisms is perhaps the best investigated even if it is not fully understood, while studies over upper organisms and speleothems in a cavern environment are scarce and details are not always given on the involved genetic mechanisms. The aim of the present paper is to give an updated overview on these topics in order to enhance the interest of …

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Studies On Certain Aspects Of Behaviour In The Blind Catfish Horaglanis Krishnai Menon, T. V. Anna Mercy, N. K. Pillai, N. K. Balasubramanian Jan 2001

Studies On Certain Aspects Of Behaviour In The Blind Catfish Horaglanis Krishnai Menon, T. V. Anna Mercy, N. K. Pillai, N. K. Balasubramanian

International Journal of Speleology

Horaglanis krishnai is a blind catfish inhabiting the dug-out wells at Kottayam, Kerala. This fish has great zoogeographical importance as a similar blind clariid, Uegitglanis zammaroni is found only in the artesian wells of the former Italian Somaliland. Studies on certain behavioural aspects of the fish in captive conditions showed that, this fish even though is blind, exhibited a high degree of thigmotactism. Locomotion, comfort behaviour, feeding and light sensitivity of the fish were studied under laboratory conditions. Though the fish is totally blind and histological study did not reveal the presence of any light sensitive structures, the fish is …

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Longshore Sediment Transport As A Function Of Energy Dissipation, Ernest R. Smith, Ping Wang Jan 2001

Longshore Sediment Transport As A Function Of Energy Dissipation, Ernest R. Smith, Ping Wang

Geology Faculty Publications

Experiments to measure waves, currents, and sediment transport rate for two breaker types, plunging and spilling, were conducted in a large-scale three-dimensional physical model. It was found that there was a large difference in cross-shore distribution and total sediment transport rate between the two breaker types. Total transport rates compared to existing predictive equations. The equations generally did not predict the data well. With the exception of the Kamphuis (1991) equation, which included a dependence on wave period, the predictive equations did not differentiate between breaker types.

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Studies On The Cranial Osteology Of The Blind Catfish Horaglanis Krishnai Menon (Pisces, Clariidae), T. V. Anna Mercy, N. Krishna Pillai Jan 2001

Studies On The Cranial Osteology Of The Blind Catfish Horaglanis Krishnai Menon (Pisces, Clariidae), T. V. Anna Mercy, N. Krishna Pillai

International Journal of Speleology

Horaglanis krishnai Menon is a blind catfish inhabiting the dug- out wells at Kottayam, Kerala, South India. Studies on the cranial osteology of the fish show that the bones on the skull are firmly articulated. The frontoparietal fontanella is very large so that the cranium virtually lacks a roof. The sphenotics and alisphenoids are hardly recognizable and the orbital bones are entirely lacking. In osteological features H. krishnai closely resembles Uegitglanis zammaroni. But in H. krishnai the orbital bones are further reduced or even absent. The fontanella is larger than that of any other known catfish. These two species …

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Classification Of Terrestrial Subterranean Fauna Of Volcanic Substrates In The Canary Islands, Josè L. Martín, Helga García, Y. P. Oromí Jan 2001

Classification Of Terrestrial Subterranean Fauna Of Volcanic Substrates In The Canary Islands, Josè L. Martín, Helga García, Y. P. Oromí

International Journal of Speleology

A system is proposed for classifying the species occurring in the hypogean environment in relation to their ecological and evolutionary characteristics. The ecological criteria utilized relate to the preferred habitat of the animals (the epigean, endogean or hypogean environment) and the evolutionary criteria specify the grade of adaptive modification in three characteristics: reduction of eyes, amount of pigmentation and extent of elongation of the appendages. The object of developing this classification is to provide a system appropriate for those regions - such as those with volcanic rocks - in which the cave faunas include elements originating in different environments, and …

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The Distribution Of Plants In Scoska Cave, North Yorkshire, And Their Relationship To Light Intensity, Allan Pentecost, Zhang Zhaohui Jan 2001

The Distribution Of Plants In Scoska Cave, North Yorkshire, And Their Relationship To Light Intensity, Allan Pentecost, Zhang Zhaohui

International Journal of Speleology

The flora of a small limestone cave was investigated. A total of 59 species was recorded (4 algae, 3 lichens, 47 bryophytes, 4 ferns, 1 angiosperm) making it bryologically the richest cave in Britain and one of the richest in Europe. All but nine of the species had been recorded from other European caves. Species-richness declined irregullarly from the entrance (relative irradiance with respect to open sky 12%) to 34m depth (rel. irradiance 0.004%). Bryophytes were found at 0-16m depth where relative irradiance declined to 0.2% and only algae were encountered at 34m depth. While irradiance, which declined exponentially, was …

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Deposition Of Calcium Carbonate In Karst Caves: Role Of Bacteria In Stiffe's Cave, Claudia Ercole, Paola Cacchio, Giorgio Cappuccio, Aldo Lepidi Jan 2001

Deposition Of Calcium Carbonate In Karst Caves: Role Of Bacteria In Stiffe's Cave, Claudia Ercole, Paola Cacchio, Giorgio Cappuccio, Aldo Lepidi

International Journal of Speleology

Bacteria make a significant contribution to the accumulation of carbonate in severa! natural habitats where large amounts of carbonates are deposited. However, the role played by microbial communities in speleothem formation (stalactites, stalagmites etc.) in caves is still unclear. In bacteria carbonate is formed by autotrophic pathways, which deplete CO2 from the environment, and by heterotrophic pathways, leading to active or passive precipitation. We isolated cultivable heterotrophic microbial strains, able to induce CaCO3 precipitation in vitro, from samples taken from speleothems in the galleries of Stiffe’s cave, L’Aquila, Italy. We found a large number of bacteria in the …

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