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2007

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Geosciences Newsletter- 2007, Department Of Geosciences Nov 2007

Geosciences Newsletter- 2007, Department Of Geosciences

Geological and Environmental Sciences News

Vol. 2, No. 3

  • Dear Friends and Alumni
  • Faculty News
  • Publications
  • Grants
  • Michigan Geological Repository for Research and Education
  • Department Updates
  • Graduate Student News
  • Internships
  • Awards and Graduations
  • Alumni News
  • Donations


Quaternary Glaciation And Hydrologic Variation In The South American Tropics As Reconstructed From The Lake Titicaca Drilling Project, Sherilyn C. Fritz, Paul A. Baker, Geoffrey O. Seltzer, Ashley Ballantyne, Pedro Tapia, Hai Cheng, R. Lawrence Edwards Nov 2007

Quaternary Glaciation And Hydrologic Variation In The South American Tropics As Reconstructed From The Lake Titicaca Drilling Project, Sherilyn C. Fritz, Paul A. Baker, Geoffrey O. Seltzer, Ashley Ballantyne, Pedro Tapia, Hai Cheng, R. Lawrence Edwards

Department of Earth and Atmospheric Sciences: Faculty Publications

A 136-m-long drill core of sediments was recovered from tropical high-altitude Lake Titicaca, Bolivia-Peru, enabling a reconstruction of past climate that spans four cycles of regional glacial advance and retreat and that is estimated to extend continuously over the last 370,000 yr. Within the errors of the age model, the periods of regional glacial advance and retreat are concordant respectively with global glacial and interglacial stages. Periods of ice advance in the southern tropical Andes generally were periods of positive water balance, as evidenced by deeper and fresher conditions in Lake Titicaca. Conversely, reduced glaciation occurred during periods of negative …


Fecal Microbe Distribution And Abundance Used As A Possible Proxy For Nutrient Source Identification In Eutrophic Wilgreen Lake, Madison County, Kentucky, Theresa A. Aguiar, Walter S. Borowski Nov 2007

Fecal Microbe Distribution And Abundance Used As A Possible Proxy For Nutrient Source Identification In Eutrophic Wilgreen Lake, Madison County, Kentucky, Theresa A. Aguiar, Walter S. Borowski

EKU Faculty and Staff Scholarship

Wilgreen Lake is a eutrophic lake that has been listed on the EPA’s 303d list as nutrient impaired. Potential sources of this impairment are from humans, cattle manure and fertilizers. We suspect that the majority of nutrients originate from human sources. As a possible proxy for nutrient input, we test our hypothesis by examining fecal microbe distribution and abundance in the lake.

We took water samples at 19 sampling locations on 4 occasions. Sampling spanned 26 June to 15 August with the last 3 sampling events occurring at roughly two-week intervals. These samples were then processed using IDEXX methods, which …


Demersal Fishes Associated With Lophelia Pertusa Coral And Hard-Substrate Biotopes On The Continental Slope, Northern Gulf Of Mexico, Kenneth J. Sulak, R. Allen Brooks, Kirsten E. Luke, April D. Norem, Michael Randall, Andrew J. Quaid, George E. Yeargin, Jana M. Miller, William M. Harden, John H. Caruso, Steve W. Ross Nov 2007

Demersal Fishes Associated With Lophelia Pertusa Coral And Hard-Substrate Biotopes On The Continental Slope, Northern Gulf Of Mexico, Kenneth J. Sulak, R. Allen Brooks, Kirsten E. Luke, April D. Norem, Michael Randall, Andrew J. Quaid, George E. Yeargin, Jana M. Miller, William M. Harden, John H. Caruso, Steve W. Ross

United States Geological Survey: Staff Publications

The demersal fish fauna of Lophelia pertusa (Linnaeus, 1758) coral reefs and associated hard-bottom biotopes was investigated at two depth horizons in the northern Gulf of Mexico using a manned submersible and remote sampling. The Viosca Knoll fauna consisted of at least 53 demersal fish species, 37 of which were documented by submersible video. On the 325 m horizon, dominant taxa determined from frame-by-frame video analysis included Stromateidae, Serranidae, Trachichthyidae, Congridae, Scorpaenidae, and Gadiformes. On the 500 m horizon, large mobile visual macrocarnivores of families Stromateidae and Serranidae dropped out, while a zeiform microcarnivore assumed importance on reef “Thicket” biotope, …


Combination Of Sar Remote Sensing And Gis For Monitoring Subglacial Volcanic Activity – Recent Results From Vatnajökull Ice Cap (Iceland), K. Scharrer, Rocco Malservisi, Ch. Mayer, O. Spieler, U. Münzer Nov 2007

Combination Of Sar Remote Sensing And Gis For Monitoring Subglacial Volcanic Activity – Recent Results From Vatnajökull Ice Cap (Iceland), K. Scharrer, Rocco Malservisi, Ch. Mayer, O. Spieler, U. Münzer

School of Geosciences Faculty and Staff Publications

This paper presents latest results from the combined use of SAR (Synthetic Aperture Radar) remote sensing and GIS providing detailed insights into recent volcanic activity under Vatnajökull ice cap (Iceland). Glaciers atop active volcanoes pose a constant potential danger to adjacent inhabited regions and infrastructure. Besides the usual volcanic hazards (lava flows, pyroclastic clouds, tephra falls, etc.), the volcano-ice interaction leads to enormous meltwater torrents (icelandic: jökulhlaup), devastating large areas in the surroundings of the affected glacier. The presented monitoring strategy addresses the three crucial questions: When will an eruption occur, where is the eruption site and which area is …


Combined Remote Sensing And Field Investigations Of Hydrocarbon Trap Analogue Structures: Examples From The Zagros Simply Folded Belt, Iran And The Sawtooth Range, Montana [Abstract], Caroline M. Burberry, David Cannon, John W. Cosgrove, Terry Engelder Nov 2007

Combined Remote Sensing And Field Investigations Of Hydrocarbon Trap Analogue Structures: Examples From The Zagros Simply Folded Belt, Iran And The Sawtooth Range, Montana [Abstract], Caroline M. Burberry, David Cannon, John W. Cosgrove, Terry Engelder

Department of Earth and Atmospheric Sciences: Faculty Publications

First paragraph of abstract: Structures that outcrop at the surface in fold-thrust belts are frequently good analogues for hydrocarbon traps in compressional environments. Along-strike changes in structure and geometry have important implications for connectivity and fluid flow throughout the petroleum system, e.g. in the Zagros Simply Folded Belt, Iran, and in a surface reservoir analogue in the Sawtooth Range, Montana.


Exceptionally Preserved Jellyfishes From The Middle Cambrian, Paulyn Cartwright, Susan L. Halgedahl, Jonathan R. Hendricks, Richard D. Jarrard, Antonio C. Marques, Allen G. Collins, Bruce S. Lieberman Oct 2007

Exceptionally Preserved Jellyfishes From The Middle Cambrian, Paulyn Cartwright, Susan L. Halgedahl, Jonathan R. Hendricks, Richard D. Jarrard, Antonio C. Marques, Allen G. Collins, Bruce S. Lieberman

Faculty Publications

Cnidarians represent an early diverging animal group and thus insight into their origin and diversification is key to understanding metazoan evolution. Further, cnidarian jellyfish comprise an important component of modern marine planktonic ecosystems. Here we report on exceptionally preserved cnidarian jellyfish fossils from the Middle Cambrian (~505 million years old) Marjum Formation of Utah. These are the first described Cambrian jellyfish fossils to display exquisite preservation of soft part anatomy including detailed features of structures interpreted as trailing tentacles and subumbrellar and exumbrellar surfaces. If the interpretation of these preserved characters is correct, their presence is diagnostic of modern jellyfish …


An Update On Groundwater Conditions At The Site Of The York College Cuny Campus In Southeastern Queens County, New York City, Nazrul I. Khandaker, Stanley Schleifer, Zarine Ali, Edward A. Molteni Oct 2007

An Update On Groundwater Conditions At The Site Of The York College Cuny Campus In Southeastern Queens County, New York City, Nazrul I. Khandaker, Stanley Schleifer, Zarine Ali, Edward A. Molteni

Publications and Research

The wells operated by the Jamaica Water Supply Company in Queens represent the only large scale utilization of groundwater for public water supply in New York City in recent years. These wells were shut down, for the most part, beginning in 1996. Since that time, water table elevations in the area, which had been drawn down by the withdrawal activity of the Jamaica Water Supply Company, have risen significantly causing some high groundwater problems, including flooding of basements. The New York City Department of Environmental Protection (NYCDEP) has held public hearings on a contemplated resumption of ground water withdrawal in …


Marks, Mary E. (Sc 1523), Manuscripts & Folklife Archives Oct 2007

Marks, Mary E. (Sc 1523), Manuscripts & Folklife Archives

MSS Finding Aids

Finding aid and full-text scan (Click on "Additional Files" below) for Manuscripts Small Collection 1523. Dissertation (126 p.; illus.; maps) by Mary E. Marks titled "The Rock Asphalt Industry of Western Kentucky" written for the Department of Geography at the University of Chicago and submitted in December 1931. Discusses several important asphalt rock mining operations in the south central section of Kentucky.


Incorporating Geostatistical Constraints In Nonlinear Inverse Problems, T. C. Johnson, Partha S. Routh, Tom Clemo, Warren Barrash, William P. Clement Oct 2007

Incorporating Geostatistical Constraints In Nonlinear Inverse Problems, T. C. Johnson, Partha S. Routh, Tom Clemo, Warren Barrash, William P. Clement

CGISS Publications and Presentations

In this paper we present a method of incorporating semivariogram constraints into nonlinear inversion problems. That is, we describe a method of sampling the space of inverse solutions that honor a specified semivariogram or set of semivariograms and also explain a set of state data. The approach can be considered a method of conditional simulation where model conditioning is based upon state data (as opposed to parameter data). The difference between this approach and other simulation approaches is that the simulation is posed as an optimization problem with the joint objective of matching the semivariograms and honoring the state data. …


Auroral Ion Outflow: Low Altitude Energization, Kristina A. Lynch, J. L. Semeter, M. Zettergren, P. Kintner, R. Arnoldy, E. Klatt, J. Labelle, R. G. Michell Oct 2007

Auroral Ion Outflow: Low Altitude Energization, Kristina A. Lynch, J. L. Semeter, M. Zettergren, P. Kintner, R. Arnoldy, E. Klatt, J. Labelle, R. G. Michell

Dartmouth Scholarship

The SIERRA nightside auroral sounding rocket made observations of the origins of ion upflow, at topside F-region altitudes (below 700 km), comparatively large topside plasma densities (above 20 000/cc), and low energies (10 eV). Upflowing ions with bulk velocities up to 2 km/s are seen in conjunction with the poleward edge of a nightside substorm arc. The upflow is limited within the poleward edge to a region (a) of northward convection, (b) where Alfvenic ´ and Pedersen conductivities are well-matched, leading to good ionospheric transmission of Alfvenic power, and (c) of ´ soft electron precipitation (below 100 eV). Models of …


A Simple Array Platform For Microrna Analysis And Its Application In Mouse Tissues, Xiaoqing Tang, Jozsef Gal, Xun Zhuang, Wang-Xia Wang, Haining Zhu, Guiliang Tang Oct 2007

A Simple Array Platform For Microrna Analysis And Its Application In Mouse Tissues, Xiaoqing Tang, Jozsef Gal, Xun Zhuang, Wang-Xia Wang, Haining Zhu, Guiliang Tang

Plant and Soil Sciences Faculty Publications

MicroRNAs (miRNAs) are a novel class of small noncoding RNAs that regulate gene expression at the post-transcriptional level and play a critical role in many important biological processes. Most miRNAs are conserved between humans and mice, which makes it possible to analyze their expressions with a set of selected array probes. Here, we report a simple array platform that can detect 553 nonredundant miRNAs encompassing the entire set of miRNAs for humans and mice. The platform features carefully selected and designed probes with optimized hybridization parameters. Potential cross-reaction between mature miRNAs and their precursors was investigated. The array platform was …


Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Quarterly Progress Report, Period Ending: October 1, 2007, Limnological Assistance For Lake Mead National Recreation Area Oct 2007

Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Quarterly Progress Report, Period Ending: October 1, 2007, Limnological Assistance For Lake Mead National Recreation Area

Limnological Studies

• Task Agreement has been formally executed

• Position description and announcement have been drafted for limnologist position

• All projects have been initiated


Seismicity In The Vicinity Of Yucca Mountain, Nevada, For The Period October 1, 2003, To September 30, 2004, David Von Seggern, Ken Smith, John G. Anderson, Amy J. Smiecinski Oct 2007

Seismicity In The Vicinity Of Yucca Mountain, Nevada, For The Period October 1, 2003, To September 30, 2004, David Von Seggern, Ken Smith, John G. Anderson, Amy J. Smiecinski

Publications (YM)

This report describes the seismicity and earthquake monitoring activities within the Yucca Mountain region during fiscal year 2004 (FY2004 - October 1, 2003, through September 30, 2004) based on operation of the Southern Great Basin Digital Seismic Network (SGBDSN). Network practices and earthquake monitoring conducted at the Nevada Seismological Laboratory (NSL) under DOE directives for prior fiscal years are covered in similar yearly reports (see references). Real-time systems, including regional data telemetry and data management at NSL, provide for the automatic determination of earthquake locations and magnitudes and notification of important earthquakes in the region to UNR staff and DOE …


Unlv Magazine, Cate Weeks, Erin O'Donnell, Shane Bevell, Barbara Cloud, Joy Drohan, Adam Baer, Holly Ivy De Vore, Gian Galassi, Eric Leake Oct 2007

Unlv Magazine, Cate Weeks, Erin O'Donnell, Shane Bevell, Barbara Cloud, Joy Drohan, Adam Baer, Holly Ivy De Vore, Gian Galassi, Eric Leake

UNLV Magazine

No abstract provided.


Geogram 2007, David J. Keeling Editor, Wku Department Of Geography And Geology Oct 2007

Geogram 2007, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.


Drought Scape- Fall 2007, The National Drought Mitigation Center Oct 2007

Drought Scape- Fall 2007, The National Drought Mitigation Center

Droughtscape, Quarterly Newsletter of NDMC, 2007-

Fall 2007 Outlook

Diverse Impacts Reported in Summer of 2007

Decadal Climate Cycles Hold Predictive Potential

Drought Experts Take Roadmap to Congress

NDMC Research Updates


Hydrological Monitoring With Hybrid Sensor Networks, Thomas V. Freiberger, Sahra Sedigh, Estella A. Atekwana Oct 2007

Hydrological Monitoring With Hybrid Sensor Networks, Thomas V. Freiberger, Sahra Sedigh, Estella A. Atekwana

Electrical and Computer Engineering Faculty Research & Creative Works

Existing hydrological monitoring systems suffer from short- comings in accuracy, resolution, and scalability. Their fragility, high power consumption, and lack of autonomy necessitate frequent site visits. Cabling requirements and large size limit their scalability and make them prohibitively expensive. The research described in this paper proposes to alleviate these problems by pairing high-resolution in situ measure- ment with remote data collection and software maintenance. A hybrid sensor network composed of wired and wireless connections autonomously measures various attributes of the soil, including moisture, temperature, and resistivity. The mea- surements are communicated to a processing server over the existing GSM cellular …


Drainage Diversion Patterns And Landform Morphology As An Indicator Of Deformation Style: Examples From The Zagros Simply Folded Belt, Islamic Republic Of Iran (Abstract), Caroline M. Burberry, John W. Cosgrove, J.-G. Liu Oct 2007

Drainage Diversion Patterns And Landform Morphology As An Indicator Of Deformation Style: Examples From The Zagros Simply Folded Belt, Islamic Republic Of Iran (Abstract), Caroline M. Burberry, John W. Cosgrove, J.-G. Liu

Department of Earth and Atmospheric Sciences: Faculty Publications

First paragraph of abstract: In the NW-SE trending Zagros Simply Folded Belt, landform organisation is shown to be a straightforward response to tectonic forcing processes using remote sensing. Two end-member fold types (detachment folds and fault-bend folds) interact with streams flowing into the Persian Gulf. Using drainage network analysis and geomorphologic methods, the organisation of emergent landform morphologies is mapped and the distribution of different fold types is inferred.


Pend Oreille River Model: Model Scenario Simulations, Robert Leslie Annear, Chris Berger, Scott A. Wells Oct 2007

Pend Oreille River Model: Model Scenario Simulations, Robert Leslie Annear, Chris Berger, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The Idaho Department of Environmental Quality is interested in developing a temperature and water quality Total Maximum Daily Load (TMDL) allocation for the Pend Oreille River between the Long Bridge near the historical Lake Pend Oreille outlet and Albeni Falls Dam (U.S. Army Corps of Engineer’s reservoir) as shown in Figure 1.

This management scenario report is an update of a prior report. The management scenarios had to be rerun because of a modeling error made with the outflows rate of Albeni Falls Dam. The new calibration error statistics were compared with the old statistics in Appendix B: Model Calibration …


Report On Mini-Workshop “Bringing Margins Science To The Classroom”, Cathy Manduca, Jeffrey G. Ryan, Don Reed Oct 2007

Report On Mini-Workshop “Bringing Margins Science To The Classroom”, Cathy Manduca, Jeffrey G. Ryan, Don Reed

Geology Faculty Publications

MARGINS has been awarded an NSF Course, Curriculum, and Laboratory Improvement (CCLI) grant to bring MARGINS research into widespread use in undergraduate teaching in ways that showcase the integrated, multidisciplinary approach that is characteristic of modern, front-line geoscience research. In collaboration with the Science Education Resource Center (SERC) at Carleton College, the project is developing a web-based collection of teaching materials referred to as “Mini-Lessons” (http://serc.carleton.edu/margins). Mini-Lessons range in scope from something as simple as the use of MARGINS science to illustrate a lecture to multi-day lab projects that capitalize on the MARGINS Data Repository. An exciting aspect of this …


Soil Survey Of The Bettink Dairy Farm, Riverway Road, Northcliffe, Peter J. Tille, Tilwin Westrup Oct 2007

Soil Survey Of The Bettink Dairy Farm, Riverway Road, Northcliffe, Peter J. Tille, Tilwin Westrup

Resource management technical reports

This soil survey of the Bettink dairy farm in Northcliffe, Western Australia aimed to: provide detailed soil descriptions to add to information associated with the environment in which the dairy industry in Western Australia is located; collect soil samples at predetermined standard depths from documented farm locations for nutrient analysis; map soils with similar characteristics based on description and analysis.


Who Will Put America Back Together Again?, David J. Keeling Sep 2007

Who Will Put America Back Together Again?, David J. Keeling

Earth, Environmental, and Atmospheric Sciences Faculty Publications

No abstract provided.


Shallow Slab Fluid Release Across And Along The Mariana Arc-Basin System: Insights From Geochemistry Of Serpentinized Peridotites From The Mariana Fore Arc, Ivan P. Savov, Jeffrey G. Ryan, Massimo D'Antonio, Patricia Fryer Sep 2007

Shallow Slab Fluid Release Across And Along The Mariana Arc-Basin System: Insights From Geochemistry Of Serpentinized Peridotites From The Mariana Fore Arc, Ivan P. Savov, Jeffrey G. Ryan, Massimo D'Antonio, Patricia Fryer

Geology Faculty Publications

Shallow slab devolatilization is not only witnessed through fluid expulsion at accretionary prisms, but is also evidenced by active serpentinite seamounts in the shallow fore-arc region of the Mariana convergent margin. Ocean Drilling Program (ODP) Leg 195 recovered serpentinized peridotites that present a unique opportunity to study the products of shallow level exchanges between the upper mantle and slab-derived fluids. Similar to samples recovered during ODP Leg 125, the protoliths of these fore-arc serpentinized peridotites are mantle harzburgites that have suffered large volume melt extraction (up to 25%) prior to interactions with fluids released from the downgoing Pacific Plate. Samples …


Contact Metamorphism In The Malashan Dome, North Himalayan Gneiss Domes, Southern Tibet: An Example Of Shallow Extensional Tectonics In The Tethys Himalaya, Tetsuo Kawakami, Mutsuki Aoya, Simon Wallis, Jeffrey Lee, Kentaro Terada, Yu Wang, Matt Heizler Sep 2007

Contact Metamorphism In The Malashan Dome, North Himalayan Gneiss Domes, Southern Tibet: An Example Of Shallow Extensional Tectonics In The Tethys Himalaya, Tetsuo Kawakami, Mutsuki Aoya, Simon Wallis, Jeffrey Lee, Kentaro Terada, Yu Wang, Matt Heizler

All Faculty Scholarship for the College of the Sciences

Combined petrographic, structural and geochronological study of the Malashan dome, one of the North Himalayan gneiss domes, reveals that it is cored by a Miocene granite, the Malashan granite, that intruded into the Jurassic sedimentary rocks of Tethys Himalaya. Two other granites in the area are referred to as the Paiku and Cuobu granites. New zircon SHRIMP U-Pb and muscovite and biotite 40Ar-39Ar dating show that the Paiku granite was emplaced during 22.2–16.2 Ma (average 19.3 ± 3.9 Ma) and cooled rapidly to 350–400 °C at around 15.9 Ma. Whole-rock granite chemistry suggests the original granitic magma …


Wetland Restoration Response Analysis Using Modis And Groundwater Data, Assefa M. Melesse, Vijay Nangia, Xixi Wang, Michael Mcclain Sep 2007

Wetland Restoration Response Analysis Using Modis And Groundwater Data, Assefa M. Melesse, Vijay Nangia, Xixi Wang, Michael Mcclain

Department of Earth and Environment

Vegetation cover and groundwater level changes over the period of restoration are the two most important indicators of the level of success in wetland ecohydrological restoration. As a result of the regular presence of water and dense vegetation, the highest evapotranspiration (latent heat) rates usually occur within wetlands. Vegetation cover and evapotranspiration of large areas of restoration like that of Kissimmee River basin, South Florida will be best estimated using remote sensing technique than point measurements. Kissimmee River basin has been the area of ecological restoration for some years. The current ecohydrological restoration activities were evaluated through fractional vegetation cover …


A Diatom Record Of Late Holocene Climate Variation In The Northern Range Of Yellowstone National Park, Usa, Brandi B. Bracht, Jeffery R. Stone, Sherilyn C. Fritz Sep 2007

A Diatom Record Of Late Holocene Climate Variation In The Northern Range Of Yellowstone National Park, Usa, Brandi B. Bracht, Jeffery R. Stone, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

The changes in diatom species composition in a sediment core from Crevice Lake, Yellowstone National Park, spanning the past 2550 yr, were used to reconstruct long-term limnological and ecological conditions that may be related to late Holocene climate variability. Planktic forms dominate the fossil diatom assemblages throughout this record, but changes in species dominance indicate varying nutrient levels over time, particularly phosphorus. The changes in the nutrient concentrations in the lake were probably driven by changes in temperature and wind strength that affected the duration of watercolumn mixing and thus the extent of nutrient recycling from deep waters. Prior to …


Organic Geochemical Investigation Of A Highly Contaminated Urban Waterway: The Gowanus Canal, Brooklyn, New York, Usa, Michael A. Kruge, Kevin K. Olsen, Eric A. Stern Sep 2007

Organic Geochemical Investigation Of A Highly Contaminated Urban Waterway: The Gowanus Canal, Brooklyn, New York, Usa, Michael A. Kruge, Kevin K. Olsen, Eric A. Stern

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The Gowanus Canal is an industrial waterway constructed in the mid-19th century by widening and deepening a natural tidal channel. It is ca. 3 km in length and empties into Gowanus Bay, an arm of New York Harbor. Its banks, reinforced by bulkheads and piers, became the site of intensive industrial activity, including oil refining, coal gasification, soap making and tanning. Even though much of the industrial activity along the canal has ceased, its sediments remain highly enriched in organic and inorganic contaminants, with combined sewer outfalls continuing to transport pollutants into the canal. The canal area remains densely …


Microbial Nanowires: Is The Subsurface "Hardwired"?, Dimitrios Ntarlagiannis, Estella A. Atekwana, Eric A. Hill, Yuri A. Gorby Sep 2007

Microbial Nanowires: Is The Subsurface "Hardwired"?, Dimitrios Ntarlagiannis, Estella A. Atekwana, Eric A. Hill, Yuri A. Gorby

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Earth's shallow subsurface results from integrated biological, geochemical, and physical processes. Methods are sought to remotely assess these interactive processes, especially those catalysed by micro-organisms. Using saturated sand columns and the metal reducing bacterium Shewanella oneidensis MR-1, we show that electrically conductive appendages called bacterial nanowires are directly associated with electrical potentials. No significant electrical potentials were detectable in columns inoculated with mutant strains that produced non-conductive appendages. Scanning electron microscopy imaging revealed a network of nanowires linking cells-cells and cells to mineral surfaces, "hardwiring" the entire length of the column. We hypothesize that the nanowires serve as conduits …


Blue Nile Incision On The Ethiopian Plateau: Pulsed Plateau Growth, Pliocene Uplift, And Hominin Evolution, Nahid D.S. Gani, M. Royhan Gani, Mohamed G. Abdel Salam Sep 2007

Blue Nile Incision On The Ethiopian Plateau: Pulsed Plateau Growth, Pliocene Uplift, And Hominin Evolution, Nahid D.S. Gani, M. Royhan Gani, Mohamed G. Abdel Salam

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The 1.6-km-deep Gorge of the Nile, a rival of the Grand Canyon, resulted from the deep incision of the Blue Nile drainage into the uplifted Ethiopian Plateau. Understanding the incision history of the plateau is crucial to unraveling the Cenozoic tectonoclimatic evolution of the region, particularly because the region has long been used as a natural laboratory to understand the geodynamics of continental rifting and the evolution of hominins. We undertake a quantitative geomorphologic approach integrating field, geographic information system (GIS), and digital elevation model (DEM) data to analyze incision (volume, long-term rates, and spatiotemporal variability) and river longitudinal profiles …