Physical Sciences and Mathematics | Open Access Articles

Interaction Of Cytochromes With Oxide Surfaces: Adsorption-Induced Conformation Change?, Carrick Eggleston, N. Khare, D. Lovelace

Carrick M Eggleston

Meeting abstract of “Interaction of Cytochromes with Oxide Surfaces: Adsorption-Induced Conformation Change?”, Mineral Surface Reactivity.

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Characterizing The 410 Km Discontinuity Low-Velocity Layer Beneath The La Ristra Array In The North American Southwest, J. J. Jasbinsek, Ken Dueker, S. M. Hansen

Ken Dueker

Receiver functions recorded by the 54-station 920 km long Program for Array Seismic Studies of the Continental Lithosphere-Incorporated Research Institutions for Seismology Colorado Plateau/Rio Grande Rift Seismic Transect Experiment (LA RISTRA) line array display a pervasive negative polarity P to S conversion (Pds) arrival preceding the positive polarity 410 km discontinuity arrival. These arrivals are modeled as a low-velocity layer atop the 410 km discontinuity (410-LVL) and are inverted for a velocity profile via a grid search using a five-parameter linear gradient velocity model. Model parameter likelihood and correlations are assessed via calculation of one-and two-dimensional marginal posterior probability distributions. …

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The Structure Of Hematite (Alpha-Fe(2)O(3)) (001) Surfaces In Aqueous Media: Scanning Tunneling Microscopy And Resonant Tunneling Calculations Of Coexisting O And Fe Terminations, Carrick Eggleston, A. G. Stack, K. M. Rosso, S. R. Higgins, A. M. Bice, S. W. Boese, R. D. Pribyl, J. J. Nichols

Carrick M Eggleston

The iron oxide-water interface is of interest not only in geochemical and environmental processes, but also in fields ranging from corrosion to photocatalysis. The structure of alpha-Fe2O3 (001) surfaces is not fully understood, and questions have arisen recently concerning different terminations of (001) terraces; a so-called Fe-termination is expected, but under some conditions an O-termination may also be possible. Ultra-high vacuum (UHV) scanning tunneling microscope (STM) studies report evidence for an O-termination in coexistence with an Fe-termination, but other studies find no evidence for an O-termination. Molecular mechanics studies suggest that an O-termination should be possible in an aqueous environment. …

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A Sporadic Low-Velocity Layer Atop The Western Us Mantle Transition Zone And Short-Wavelength Variations In Transition Zone Discontinuities, B. Schmandt, Ken Dueker, S. M. Hansen, J. J. Jasbinsek, Z. Zhang

Ken Dueker

Teleseismic receiver function analysis of data from six dense arrays in the western U. S. is used to investigate mantle transition zone (MTZ) discontinuities and the prevalence of a low-velocity layer atop the 410 km discontinuity (410-LVL). Negative polarity Ps arrivals indicative of a low-velocity layer with a top 25-60 km above the 410 are identified in 8-11 out of 18 stacks of receiver functions from highly sampled back azimuth corridors. The 410-LVL is interpreted as partial melt resulting from upwelling of hydrated mantle across a water solubility contrast at the 410. The 669 km mean depth of the 660 …

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Teleseismic P-Wave Tomogram Of The Yellowstone Plume, H. Y. Yuan, Ken Dueker

Ken Dueker

Inversion of a new data set of teleseismic P-wave travel-times from three PASSCAL seismic deployments around the Yellowstone hotspot reveals a 100 km diameter upper mantle plume that extends from the Yellowstone volcanic caldera to 500 km depth and dips 20 degrees to the northwest. A monotonic decrease in the velocity perturbation of the plume from -3.2% at 100 km to -0.9% at 450 km is consistent with a uniform thermal anomaly of 180 degrees C. Where the plume crosses the 410 km discontinuity, previous research shows a depression in the 410 km discontinuity consistent with a warm plume ( …

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Redox-Linked Conformation Change And Electron Transfer Between Monoheme C-Type Cytochromes And Oxides, N. Khare, D. M. Lovelace, Carrick Eggleston, M. Swenson, T. S. Magnuson

Carrick M Eggleston

Electron transfer between redox active proteins and mineral oxides is important in a variety of natural as well as technological processes, including electron transfer from dissimilatory metal-reducing bacteria to minerals. One of the pathways that could trigger electron transfer between proteins and minerals is redox-linked conformation change. We present electrochemical evidence that mitochondrial cytochrorne c (Mee) undergoes significant conformation change upon interaction with hematite and indiurn-tin oxide (ITO) surfaces. The apparent adsorption-induced conformation change causes the protein to become more reducing, which makes it able to transfer electrons to the hematite conduction band. Although Mcc is not a protein thought …

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Signal-To-Noise Ratios Of Teleseismic Receiver Functions And Effectiveness Of Stacking For Their Enhancement, I. B. Morozov, Ken G. Dueker

Ken Dueker

[1] We present a method for the measurement of spatially variable signal-to-noise (S/N) ratios in multichannel teleseismic receiver function (RF) images. The S/N ratio is defined as a measure of coherency of the final image, and the approach is applicable to any RF imaging technique that employs mapping of the records into depth followed by their summation as the final signal enhancement step. In such methods, all of the converted phases become horizontally aligned in the depth domain, and their coherent (signal) and incoherent (noise) components can be estimated by using stacking statistics. For 10 locations along two subarrays of …

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Adatom Fe(Iii) On The Hematite Surface: Observation Of A Key Reactive Surface Species, Carrick Eggleston, A. G. Stack, K. M. Rosso, A. M. Bice

Carrick M Eggleston

The reactivity of a mineral surface is determined by the variety and population of different types of surface sites (e.g., step, kink, adatom, and defect sites). The concept of "adsorbed nutrient" has been built into crystal growth theories, and many other studies of mineral surface reactivity appeal to ill-defined "active sites." Despite their theoretical importance, there has been little direct experimental or analytical investigation of the structure and properties of such species. Here, we use ex-situ and in-situ scanning tunneling microcopy (STM) combined with calculated images based on a resonant tunneling model to show that observed nonperiodic protrusions and depressions …

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Cobalt Reactive Transport And Solid Solution At The Calcite-Water Interface At 40 Degrees C, B. Greer, Carrick M. Eggleston, S. R. Higgins

Carrick M Eggleston

Meeting Abstract for “Cobalt Reactive Transport and Solid Solution At the Calcite-Water Interface At 40 Degrees C,” Copenhagen.

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Synthesis Of Mineral Semiconductor Thin Films: Toward Mineral-Based Photosynthesis, A. J. Moyer, Aj. A. Shankle, Carrick Eggleston, C. J. Botiman, N. Swoboda-Colerg

Carrick M Eggleston

Meeting abstract for "Synthesis of Mineral Semiconductor Thin Films: Toward Mineral-Based Photosynthesis."

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Upper Mantle P-Wave Velocity Structure From Passcal Teleseismic Transects Across Idaho, Wyoming And Colorado, Ken Dueker, H. Y. Yuan

Ken Dueker

Inversion of teleseismic P-time residuals along two linear seismic arrays provides well-resolved inverse images of the upper mantle. Low velocity bodies beneath the Yellowstone Hotspot Track and the Grand Mesa volcanic field in western Colorado are similar in shape and magnitude. In the two places where our transects cross the 1.78 Ga Archean-Proterozoic Cheyenne suture, high velocities are imaged to 150 km. Beneath the Leucite Hills volcanic field in Wyoming a small upper mantle low velocity body is imaged. Whether these anomalies are lithospheric or asthenospheric in origin is poorly constrained, but the consistent high velocities beneath the Cheyenne suture …

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Nonvolcanic Seafloor Spreading And Corner-Flow Rotation Accommodated By Extensional Faulting At 15 Degrees N On The Mid-Atlantic Ridge: A Structural Synthesis Of Odp Leg 209, T. Schroeder, H.J.B. Dick, U. Faul, J. F. Casey, P. B. Kelemen

Michael Cheadle

[1] Drilling during ODP Leg 209, dredging, and submersible dives have delineated an anomalous stretch of the Mid-Atlantic Ridge north and south of the 15 degrees 20'N Fracture Zone. The seafloor here consists dominantly of mantle peridotite with gabbroic intrusions that in places is covered by a thin, discontinuous extrusive volcanic layer. Thick lithosphere ( 10 - 20 km) in this region inhibits magma from reaching shallow levels beneath the ridge axis, thereby causing plate accretion to be accommodated by extensional faulting rather than magmatism. The bathymetry and complex fault relations in the drill-core suggest that mantle denudation and spreading …

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Inherited Zircon And The Magmatic Construction Of Oceanic Crust, J. J. Schwartz, Barbara John, Michael Cheadle, C. Grimes, E. A. Miranda, J. L. Wooden, H.J.B. Dick

Michael Cheadle

Meeting Abstract for “Inherited Zircon and the Magmatic Construction of Oceanic Crust,” Goldschmidt Conference Abstracts 2005, Geochronology of Tectonic Processes.

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Quantitative Modeling Of Granitic Melt Generation And Segregation In The Continental Crust, M. D. Jackson, Michael Cheadle, M. P. Atherton

Michael Cheadle

We present a new quantitative model of granitic (in a broad sense) melt generation and segregation within the continental crust. We assume that melt generation is caused by the intrusion of hot, mantle-derived basalt, and that segregation occurs by buoyancy-driven flow along grain edges coupled with compaction of the partially molten source rock. We solve numerically the coupled equations governing heating, melting, and melt migration in the source rock, and cooling and crystallization in the underlying heat source. Our results demonstrate that the spatial distribution and composition of the melt depends upon the relative upward transport rates of heat and …

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Temperatures In Ambient Mantle And Plumes: Constraints From Basalts, Picrites, And Komatiites, C. Herzberg, P. D. Asimow, N. Arndt, Y. L. Niu, C. M. Lesher, J. G. Fitton, Michael Cheadle, A. D. Saunders

Michael Cheadle

[1] Several methods have been developed to assess the thermal state of the mantle below oceanic ridges, islands, and plateaus, on the basis of the petrology and geochemistry of erupted lavas. One leads to the conclusion that mantle potential temperature (i.e., T_P) of ambient mantle below oceanic ridges is 1430 degrees C, the same as Hawaii. Another has ridges with a large range in ambient mantle potential temperature (i.e., T_P = 1300 - 1570 degrees C), comparable in some cases to hot spots ( Klein and Langmuir, 1987; Langmuir et al., 1992). A third has uniformly low …

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Using Marine Snails To Teach Biogeography And Macroevolution: The Role Of Larvae And Dispersal Ability In The Evolution And Persistence Of Species, Jonathan R. Hendricks

Jonathan R. Hendricks

While some marine animals are capable of traveling great distances, many have limited mobility as adults and spend the majority of their lifetimes in a small geographical area or may even be cemented to a single place. While it might be expected that species with limited mobility would have small geographic distributions, some nevertheless occur over very large areas. This is the case for some marine snails (gastropods). A key factor that impacts the geographic distribution of marine snails is the type of larvae they have during the phase of their life history that follows hatching from an egg. Because …

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Searching For Pre-Lan Na Cities In The Golden Triangle Area, Thailand And Laos, Spencer H. Wood

Spencer H. Wood

No abstract provided.

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Clay Fabric And Mass Physical Properties Of Surficial Marine Sediment Near The Deepwater Horizon Oil Spill, Andrew Head, Richard H. Bennett, Jessica R. Douglas, Kenneth J. Curry

Kenneth J. Curry

Surficial sediment was obtained on the RV Cape Hatteras Cruise (2010) from the seafloor at a water depth of 1570 meters located at latitude 28°44'20.16"N and longitude 88°20'24.96"W in close proximity to the Deepwater Horizon well, Gulf of Mexico. Preliminary clay nano- and microfabric observation using a transmission electron microscope (TEM) depicted a sediment rich in clays and organic matter (OM) especially in the upper 2 cm subbottom. Initial analysis of TEM micrographs depicted a high porosity clay sediment. Initial study of the mass physical properties revealed water content ωt = 67.32 – 67.28% (percent total mass), porosity n= 84.1 …

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Mapping Lava Flows From Nyamuragira Volcano (1967-2011) With Satellite Data And Automated Classification Methods, Elisabet Head, Ann L. Maclean, Simon A. Carn

Elisabet Head

The volume, location and extent of historical lava flows are important when assessing volcanic hazards, as well as the productivity or longevity of a volcanic system. We use a Landsat/Hyperion/ALI dataset and automated classification methods to map lava flows at Nyamuragira volcano (1967-2011) in the Democratic Republic of the Congo. The humid tropical climate ofNyamuragira is advantageous because its lava flows are emplaced onto heavily forested flanks, resulting in strong contrast between lava and vegetation, which contributes to efficient flow mapping. With increasing age, there is an increase in Landsat band-4 reflectance, suggesting lava flow revegetation with time. This results …

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A Comparison Of Three Terrain Parameters That May Be Used To Identify Denudation Surfaces Within A Gis: A Case Study From Wales, United Kingdom., Matt D. Rowberry

Matt D Rowberry

The study of denudation surfaces has long formed a major theme within geomorphic and tectonic research. This paper describes the computational methods used to identify these surfaces through three terrain parameters within a GIS. The investigated parameters are slope angle, relative relief, and the elevation-relief ratio. The study area under consideration is that of Wales, United Kingdom. The SRTM DEM forms the basis of this investigation, with all data interrogation undertaken in ArcMap 9.3. The computational methods are described in detail and then the results relating to each terrain parameter are compared. The denudation surface maps based on slope angle …

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The Monitoring Of Slow Moving Landslides And Assessment Of Stabilisation Measures Using An Optical-Mechanical Crack Gauge, Jan Klimeš, Matt D. Rowberry, Jan Blahůt, Miloš Briestenský, Filip Hartvich, Blahoslav Košťák, Jan Rybář, Josef Stemberk, Petra Štěpančíková

Matt D Rowberry

It is possible to monitor slow moving landslides and assess landslide stabilisation measures over protracted periods using an optical-mechanical crack gauge, called a TM-71. This technical note outlines the theoretical background to the gauge and illustrates its practical application through a number of case studies. These studies are drawn from a range of landslide types and stabilisation measures. In terms of monitoring slow moving landslides, three studies of deep-seated deformations are presented. The Taukliman coastal landslide on the Black Sea Coast is characterised by vertical and horizontal displacements of up to 0.2 mm.yr-1 and sudden earthquake-induced dilations of up to …

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Subsurface Facies Analysis Of The Late Cambrian Mt. Simon Sandstone In Western Ohio (Midcontinent, U.S.A.), James E. Evans

James E. Evans

No abstract provided.

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Determination Of Paleoearthquake Timing And Magnitudes On The Southern Segment Of The East Cache Fault, Utah, James P. Mccalpin

James P. McCalpin

We investigated the late Quaternary rupture history of the southern East Cache Fault zone [ECFZ], northern Utah with geologic mapping, paleoseismic logging of fault trenches, ground-penetrating radar, and optically stimulated luminescence dating. McCalpin (1989) indicated that the southern segment of the ECFZ consisted of three strands. We excavated four trenches across these strands, and evaluate the stratigraphy and structure of the sites. We conclude that the western fault strand of the ECFZ has had no late Quaternary displacement or does not exist; the central strand has not had any late Quaternary movement and may be a drape fold; and the …

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Evaluating Potential Post-Flood Boundaries With Biostratigraphy--The Pliocene/Pleistocene Boundary, Marcus R. Ross

Marcus R. Ross

Here I report a biostratigraphic analysis of 303 genera from 28 North American terrestrial mammalian families, in which all families contain members that are either extant or last appear in Pliocene or Pleistocene deposits. The distribution of these taxa within the Cenozoic rock record is used to evaluate proposed demarcations for the Flood/post-Flood boundary. A pronounced biostratigraphic break is expected at the Flood/post-Flood boundary since the final devastation and burial of pre-Flood nephesh creatures should be stratigraphically overlain by the arrival of post-Flood migrants. It is found that when the Flood/post-Flood boundary is placed at or near the Pliocene/Pleistocene boundary, …

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Sharks Of The Devonian, Andrew Blitman

Andrew Blitman

No abstract provided.

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Reverse Drag Revisited: Why Footwall Deformation May Be The Key To Inferring Listric Fault Geometry, Phillip G. Resor, David D. Pollard

Phillip G Resor

Although reverse drag, the down warping of hanging wall strata toward a normal fault, is widely accepted as an indicator of listric fault geometry, previous studies have shown that similar folding may form in response to slip on faults of finite vertical extent with listric or planar geometry. In this study we therefore seek more general criteria for inferring subsurface fault geometry from observations of near-surface deformation by directly comparing patterns of displacement, stress, and strain around planar and listric faults, as predicted by elastic boundary element models. In agreement with previous work, we find that models with finite planar, …

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Full-Text Articles in Physical Sciences and Mathematics

Interaction Of Cytochromes With Oxide Surfaces: Adsorption-Induced Conformation Change?, Carrick Eggleston, N. Khare, D. Lovelace

Carrick M Eggleston

Characterizing The 410 Km Discontinuity Low-Velocity Layer Beneath The La Ristra Array In The North American Southwest, J. J. Jasbinsek, Ken Dueker, S. M. Hansen

Ken Dueker

The Structure Of Hematite (Alpha-Fe(2)O(3)) (001) Surfaces In Aqueous Media: Scanning Tunneling Microscopy And Resonant Tunneling Calculations Of Coexisting O And Fe Terminations, Carrick Eggleston, A. G. Stack, K. M. Rosso, S. R. Higgins, A. M. Bice, S. W. Boese, R. D. Pribyl, J. J. Nichols

Carrick M Eggleston

A Sporadic Low-Velocity Layer Atop The Western Us Mantle Transition Zone And Short-Wavelength Variations In Transition Zone Discontinuities, B. Schmandt, Ken Dueker, S. M. Hansen, J. J. Jasbinsek, Z. Zhang

Ken Dueker

Teleseismic P-Wave Tomogram Of The Yellowstone Plume, H. Y. Yuan, Ken Dueker

Ken Dueker

Redox-Linked Conformation Change And Electron Transfer Between Monoheme C-Type Cytochromes And Oxides, N. Khare, D. M. Lovelace, Carrick Eggleston, M. Swenson, T. S. Magnuson

Carrick M Eggleston

Signal-To-Noise Ratios Of Teleseismic Receiver Functions And Effectiveness Of Stacking For Their Enhancement, I. B. Morozov, Ken G. Dueker

Ken Dueker

Adatom Fe(Iii) On The Hematite Surface: Observation Of A Key Reactive Surface Species, Carrick Eggleston, A. G. Stack, K. M. Rosso, A. M. Bice

Carrick M Eggleston

Cobalt Reactive Transport And Solid Solution At The Calcite-Water Interface At 40 Degrees C, B. Greer, Carrick M. Eggleston, S. R. Higgins

Carrick M Eggleston

Synthesis Of Mineral Semiconductor Thin Films: Toward Mineral-Based Photosynthesis, A. J. Moyer, Aj. A. Shankle, Carrick Eggleston, C. J. Botiman, N. Swoboda-Colerg

Carrick M Eggleston

Upper Mantle P-Wave Velocity Structure From Passcal Teleseismic Transects Across Idaho, Wyoming And Colorado, Ken Dueker, H. Y. Yuan

Ken Dueker

Nonvolcanic Seafloor Spreading And Corner-Flow Rotation Accommodated By Extensional Faulting At 15 Degrees N On The Mid-Atlantic Ridge: A Structural Synthesis Of Odp Leg 209, T. Schroeder, H.J.B. Dick, U. Faul, J. F. Casey, P. B. Kelemen

Michael Cheadle

Inherited Zircon And The Magmatic Construction Of Oceanic Crust, J. J. Schwartz, Barbara John, Michael Cheadle, C. Grimes, E. A. Miranda, J. L. Wooden, H.J.B. Dick

Michael Cheadle

Quantitative Modeling Of Granitic Melt Generation And Segregation In The Continental Crust, M. D. Jackson, Michael Cheadle, M. P. Atherton

Michael Cheadle

Temperatures In Ambient Mantle And Plumes: Constraints From Basalts, Picrites, And Komatiites, C. Herzberg, P. D. Asimow, N. Arndt, Y. L. Niu, C. M. Lesher, J. G. Fitton, Michael Cheadle, A. D. Saunders

Michael Cheadle

Using Marine Snails To Teach Biogeography And Macroevolution: The Role Of Larvae And Dispersal Ability In The Evolution And Persistence Of Species, Jonathan R. Hendricks

Jonathan R. Hendricks

Searching For Pre-Lan Na Cities In The Golden Triangle Area, Thailand And Laos, Spencer H. Wood

Spencer H. Wood

Clay Fabric And Mass Physical Properties Of Surficial Marine Sediment Near The Deepwater Horizon Oil Spill, Andrew Head, Richard H. Bennett, Jessica R. Douglas, Kenneth J. Curry

Kenneth J. Curry

Mapping Lava Flows From Nyamuragira Volcano (1967-2011) With Satellite Data And Automated Classification Methods, Elisabet Head, Ann L. Maclean, Simon A. Carn

Elisabet Head

A Comparison Of Three Terrain Parameters That May Be Used To Identify Denudation Surfaces Within A Gis: A Case Study From Wales, United Kingdom., Matt D. Rowberry

Matt D Rowberry

The Monitoring Of Slow Moving Landslides And Assessment Of Stabilisation Measures Using An Optical-Mechanical Crack Gauge, Jan Klimeš, Matt D. Rowberry, Jan Blahůt, Miloš Briestenský, Filip Hartvich, Blahoslav Košťák, Jan Rybář, Josef Stemberk, Petra Štěpančíková

Matt D Rowberry

Subsurface Facies Analysis Of The Late Cambrian Mt. Simon Sandstone In Western Ohio (Midcontinent, U.S.A.), James E. Evans

James E. Evans

Determination Of Paleoearthquake Timing And Magnitudes On The Southern Segment Of The East Cache Fault, Utah, James P. Mccalpin

James P. McCalpin

Evaluating Potential Post-Flood Boundaries With Biostratigraphy--The Pliocene/Pleistocene Boundary, Marcus R. Ross

Marcus R. Ross

Sharks Of The Devonian, Andrew Blitman

Andrew Blitman

Reverse Drag Revisited: Why Footwall Deformation May Be The Key To Inferring Listric Fault Geometry, Phillip G. Resor, David D. Pollard

Phillip G Resor