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Northern Florida reef tract benthic metabolism scaled by remote sensing Northern Florida reef tract benthic metabolism scaled by remote sensing

Holistic rates of excess organic carbon production (E) and calcification for a 0.5 km2 segment of the backreef platform of the northern Florida reef tract (NFRT) were estimated by combining biotope mapping using remote sensing with community metabolic rates determined with a benthic incubation system. The use of ASTER multispectral satellite imaging for the spatial scaling of benthic...
Authors
J. C. Brock, K. K. Yates, R. B. Halley, I. B. Kuffner, C. W. Wright, B.G. Hatcher

On the absence of InSAR-detected volcano deformation spanning the 1995-1996 and 1999 eruptions of Shishaldin Volcano, Alaska On the absence of InSAR-detected volcano deformation spanning the 1995-1996 and 1999 eruptions of Shishaldin Volcano, Alaska

Shishaldin Volcano, a large, frequently active basaltic-andesite volcano located on Unimak Island in the Aleutian Arc of Alaska, had a minor eruption in 1995–1996 and a VEI 3 sub-Plinian basaltic eruption in 1999. We used 21 synthetic aperture radar images acquired by ERS-1, ERS-2, JERS-1, and RADARSAT-1 satellites to construct 12 coherent interferograms that span most of the 1993–2003...
Authors
S.C. Moran, O. Kwoun, Timothy Masterlark, Z. Lu

Magnesium content within the skeletal architecture of the coral Montastraea faveolata: locations of brucite precipitation and implications to fine-scale data fluctuations Magnesium content within the skeletal architecture of the coral Montastraea faveolata: locations of brucite precipitation and implications to fine-scale data fluctuations

Small portions of coral cores were analyzed using a high-resolution laser ablation inductively coupled plasma mass spectrometer (LA ICP-MS) to determine the geochemical signatures within and among specific skeletal structures in the large framework coral, Montastraea faveolata. Vertical transects were sampled along three parallel skeletal structures: endothecal (septal flank), corallite...
Authors
N.A. Buster, C. W. Holmes

Piggyback tectonics: Long-term growth of Kilauea on the south flank of Mauna Loa Piggyback tectonics: Long-term growth of Kilauea on the south flank of Mauna Loa

Compositional and age data from offshore pillow lavas and volcaniclastic sediments, along with on-land geologic, seismic, and deformation data, provide broad perspectives on the early growth of Kilauea Volcano and the long-term geometric evolution of its rift zones. Sulfur-rich glass rinds on pillow lavas and volcaniclastic sediments derived from them document early underwater growth of...
Authors
Peter W. Lipman, Thomas W. Sisson, Michelle L. Coombs, Andrew T. Calvert, Jun-Ichi Kimura

Nature and origin of the hematite-bearing plains of Terra Meridiani based on analyses of orbital and Mars Exploration rover data sets Nature and origin of the hematite-bearing plains of Terra Meridiani based on analyses of orbital and Mars Exploration rover data sets

The ∼5 km of traverses and observations completed by the Opportunity rover from Endurance crater to the Fruitbasket outcrop show that the Meridiani plains consist of sulfate‐rich sedimentary rocks that are largely covered by poorly‐sorted basaltic aeolian sands and a lag of granule‐sized hematitic concretions. Orbital reflectance spectra obtained by Mars Express OMEGA over this region...
Authors
R. E. Arvidson, F. Poulet, R.V. Morris, J.-P. Bibring, J.F. Bell, S. W. Squyres, P. R. Christensen, G. Bellucci, B. Gondet, B.L. Ehlmann, W. H. Farrand, R.L. Fergason, M. Golombeck, J.L. Griffes, J. Grotzinger, E.A. Guinness, Kenneth E. Herkenhoff, J. R. Johnson, G. Klingelhofer, Y. Langevin, D. Ming, K. Seelos, R.J. Sullivan, J.G. Ward, S.M. Wiseman, M.J. Wolff

Parameterization and simulation of near bed orbital velocities under irregular waves in shallow water Parameterization and simulation of near bed orbital velocities under irregular waves in shallow water

A set of empirical formulations is derived that describe important wave properties in shallow water as functions of commonly used parameters such as wave height, wave period, local water depth and local bed slope. These wave properties include time varying near-bed orbital velocities and statistical properties such as the distribution of wave height and wave period. Empirical expressions...
Authors
B. Elfrink, D.M. Hanes, B.G. Ruessink

Modeling regional initiation of rainfall-induced shallow landslides in the eastern Umbria Region of central Italy Modeling regional initiation of rainfall-induced shallow landslides in the eastern Umbria Region of central Italy

We model the rainfall-induced initiation of shallow landslides over a broad region using a deterministic approach, the Transient Rainfall Infiltration and Grid-based Slope-stability (TRIGRS) model that couples an infinite-slope stability analysis with a one-dimensional analytical solution for transient pore pressure response to rainfall infiltration. This model permits the evaluation of...
Authors
D. Salciarini, J. W. Godt, W. Z. Savage, P. Conversini, R.L. Baum, J. A. Michael

Palaeomagnetic intensities from 14C-dated lava flows on the Big Island, Hawaii: 0-21 kyr Palaeomagnetic intensities from 14C-dated lava flows on the Big Island, Hawaii: 0-21 kyr

Thellier–Thellier experiments were carried out on 216 lava samples collected by the USGS on the Big Island. 35 individual flows from the Kilauea, Mauna Loa and Hualalai volcanoes are represented and independent radiocarbon dating of the flows yields absolute ages ranging from 290 to 20,240 yrs old. The palaeomagnetic analysis was carried out at the Laboratoire des Sciences du Climat et...
Authors
Nicola Pressling, Carlo Laj, Catherie Kissel, Duane E. Champion, David Gubbins

Evolution of a Holocene delta driven by episodic sediment delivery and coseismic deformation, Puget Sound, Washington, USA Evolution of a Holocene delta driven by episodic sediment delivery and coseismic deformation, Puget Sound, Washington, USA

Episodic, large-volume pulses of volcaniclastic sediment and coseismic subsidence of the coast have influenced the development of a late Holocene delta at southern Puget Sound. Multibeam bathymetry, ground-penetrating radar (GPR) and vibracores were used to investigate the morphologic and stratigraphic evolution of the Nisqually River delta. Two fluvial–deltaic facies are recognized on...
Authors
W. A. Barnhardt, B.L. Sherrod

Local thickening of the Cascadia forearc crust and the origin of seismic reflectors in the uppermost mantle Local thickening of the Cascadia forearc crust and the origin of seismic reflectors in the uppermost mantle

Seismic reflection profiles from three different surveys of the Cascadia forearc are interpreted using P wave velocities and relocated hypocentres, which were both derived from the first arrival travel time inversion of wide-angle seismic data and local earthquakes. The subduction decollement, which is characterized beneath the continental shelf by a reflection of 0.5 s duration, can be...
Authors
A.J. Calvert, K. Ramachandran, H. Kao, M. A. Fisher

Are migrating raptors guided by a geomagnetic compass? Are migrating raptors guided by a geomagnetic compass?

We tested whether routes of raptors migrating over areas with homogeneous topography follow constant geomagnetic courses more or less closely than constant geographical courses. We analysed the routes taken over land of 45 individual raptors tracked by satellite-based radiotelemetry: 25 peregrine falcons, Falco peregrinus, on autumn migration between North and South America, and seven...
Authors
Kasper Thorup, Mark R. Fuller, T. Alerstam, M. Hake, N. Kjellen, R. Standberg

Aqueous processes at Gusev crater inferred from physical properties of rocks and soils along the Spirit traverse Aqueous processes at Gusev crater inferred from physical properties of rocks and soils along the Spirit traverse

Gusev crater was selected as the landing site for Spirit on the basis of morphological evidence of long-lasting water activity, including possibly fluvial and lacustrine episodes. From the Columbia Memorial Station to the Columbia Hills, Spirit's traverse provides a journey back in time, from relatively recent volcanic plains showing little evidence for aqueous processes up to the older...
Authors
N.A. Cabrol, J.D. Farmer, E.A. Grin, L. Ritcher, L. Soderblom, R. Li, Kenneth E. Herkenhoff, G. A. Landis, R. E. Arvidson
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