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Full-Text Articles in Geology
Slip Distribution Of The 2014 Mw=8.1 Pisagua, Northern Chile, Earthquake Sequence Estimated From Coseismic Fore-Arc Surface Cracks, John P. Loveless, Chelsea P. Scott, Richard W. Allmendinger, Gabriel González
Slip Distribution Of The 2014 Mw=8.1 Pisagua, Northern Chile, Earthquake Sequence Estimated From Coseismic Fore-Arc Surface Cracks, John P. Loveless, Chelsea P. Scott, Richard W. Allmendinger, Gabriel González
Geosciences: Faculty Publications
The 2014 Mw = 8.1 Iquique (Pisagua), Chile, earthquake sequence ruptured a segment of the Nazca-South America subduction zone that last hosted a great earthquake in 1877. The sequence opened >3700 surface cracks in the fore arc of decameter-scale length and millimeter-to centimeter-scale aperture. We use the strikes of measured cracks, inferred to be perpendicular to coseismically applied tension, to estimate the slip distribution of the main shock and largest aftershock. The slip estimates are compatible with those based on seismic, geodetic, and tsunami data, indicating that geologic observations can also place quantitative constraints on rupture properties. The earthquake sequence …
Interseismic Deformation And Moment Deficit Along The Manila Subduction Zone And The Philippine Fault System, Ya-Ju Hsu, Shui-Beih Yu, John P. Loveless, Teresito Bacolcol, Renato Solidum, Artemio Luis Jr., Alfie Pelicano, Jochen Woessner
Interseismic Deformation And Moment Deficit Along The Manila Subduction Zone And The Philippine Fault System, Ya-Ju Hsu, Shui-Beih Yu, John P. Loveless, Teresito Bacolcol, Renato Solidum, Artemio Luis Jr., Alfie Pelicano, Jochen Woessner
Geosciences: Faculty Publications
We examine interseismic coupling of the Manila subduction zone and fault activity in the Luzon area using a block model constrained by GPS data collected from 1998 to 2015. Estimated long-term slip rates along the Manila subduction zone show a gradual southward decrease from 90–100 mm/yr at the northwest tip of Luzon to 65–80 mm/yr at the southern portion of the Manila Trench. We provide two block models (models A and B) to illustrate possible realizations of coupling along the Manila Trench, which may be used to infer future earthquake rupture scenarios. Model A shows a low coupling ratio …
Extinction Intensity, Selectivity And Their Combined Macroevolutionary Influence In The Fossil Record, Jonathan L. Payne, Andrew M. Bush, Ellen T. Chang, Noel A. Heim, Matthew L. Knope, Sara B. Pruss
Extinction Intensity, Selectivity And Their Combined Macroevolutionary Influence In The Fossil Record, Jonathan L. Payne, Andrew M. Bush, Ellen T. Chang, Noel A. Heim, Matthew L. Knope, Sara B. Pruss
Geosciences: Faculty Publications
The macroevolutionary effects of extinction derive from both intensity of taxonomic losses and selectivity of losses with respect to ecology, physiology and/or higher taxonomy. Increasingly, palaeontologists are using logistic regression to quantify extinction selectivity because the selectivity metric is independent of extinction intensity and multiple predictor variables can be assessed simultaneously. We illustrate the use of logistic regression with an analysis of physiological buffering capacity and extinction risk in the Phanerozoic marine fossil record. We propose the geometric mean of extinction intensity and selectivity as a metric for the influence of extinction events. The end-Permian mass extinction had the largest …
Contrasting Sediment Melt And Fluid Signatures For Magma Components In The Aeolian Arc: Implications For Numerical Modeling Of Subduction Systems, Denis Zamboni, Esteban Gazel, Jeffrey G. Ryan, Claudia Cannatelli, Federico Lucchi, Zachary D. Atlas, Jarek Trela, Sarah E. Mazza, Benedetto De Vivo
Contrasting Sediment Melt And Fluid Signatures For Magma Components In The Aeolian Arc: Implications For Numerical Modeling Of Subduction Systems, Denis Zamboni, Esteban Gazel, Jeffrey G. Ryan, Claudia Cannatelli, Federico Lucchi, Zachary D. Atlas, Jarek Trela, Sarah E. Mazza, Benedetto De Vivo
Geosciences: Faculty Publications
The complex geodynamic evolution of Aeolian Arc in the southern Tyrrhenian Sea resulted in melts with some of the most pronounced along the arc geochemical variation in incompatible trace elements and radiogenic isotopes worldwide, likely reflecting variations in arc magma source components. Here we elucidate the effects of subducted components on magma sources along different sections of the Aeolian Arc by evaluating systematics of elements depleted in the upper mantle but enriched in the subducting slab, focusing on a new set of B, Be, As, and Li measurements. Based on our new results, we suggest that both hydrous fluids and …
A High-Resolution Mid-Pleistocene Temperature Record From Arctic Lake El'gygytgyn: A 50 Kyr Super Interglacial From Mis 33 To Mis 31?, Gregory De Wet, Isla S. Castañeda, Robert M. Deconto, Julie Brigham-Grette
A High-Resolution Mid-Pleistocene Temperature Record From Arctic Lake El'gygytgyn: A 50 Kyr Super Interglacial From Mis 33 To Mis 31?, Gregory De Wet, Isla S. Castañeda, Robert M. Deconto, Julie Brigham-Grette
Geosciences: Faculty Publications
Previous periods of extreme warmth in Earth's history are of great interest in light of current and predicted anthropogenic warming. Numerous so called "super interglacial" intervals, with summer temperatures significantly warmer than today, have been identified in the 3.6 million year (Ma) sediment record from Lake El'gygytgyn, northeast Russia. To date, however, a high-resolution paleotemperature reconstruction from any of these super interglacials is lacking. Here we present a paleotemperature reconstruction based on branched glycerol dialkyl glycerol tetraethers (brGDGTs) from Marine Isotope Stages (MIS) 35 to MIS 29, including super interglacial MIS 31. To investigate this period in detail, samples were …
Two Decades Of Spatiotemporal Variations In Subduction Zone Coupling Offshore Japan, John P. Loveless, Brendan J. Meade
Two Decades Of Spatiotemporal Variations In Subduction Zone Coupling Offshore Japan, John P. Loveless, Brendan J. Meade
Geosciences: Faculty Publications
Spatial patterns of interplate coupling on global subduction zones can be used to guide seismic hazard assessment, but estimates of coupling are often constrained using a limited temporal range of geodetic data. Here we analyze ∼19 years of geodetic observations from the GEONET network to assess time-dependent variations in the spatial distribution of coupling on the subduction zones offshore Japan. We divide the position time series into five, ∼3.75-year epochs each decomposed into best-fit velocity, annual periodic signals, coseismic offsets, and postseismic effects following seven major earthquakes. Nominally interseismic velocities are interpreted in terms of a combination of tectonic block …
Documentation Of Extensive Root Systems Of Thalassia Seagrass Along The Banks Of Pigeon Creek, San Salvador Island, Bahamas, Bosiljka Glumac, H. Allen Curran
Documentation Of Extensive Root Systems Of Thalassia Seagrass Along The Banks Of Pigeon Creek, San Salvador Island, Bahamas, Bosiljka Glumac, H. Allen Curran
Geosciences: Faculty Publications
Reprinted from: Bosiljka Glumac & Michael Savarese (eds.), Proceedings of the 16th Symposium on the Geology of the Bahamas and Other Carbonate Regions: San Salvador, Gerace Research Center
Quantifying Exceptionally Large Populations Of Acropora Spp. Corals Off Belize Using Sub-Meter Satellite Imagery Classification, James Busch, Lisa Greer, David Harbor, Karl Wirth, Halard Lescinsky, H. Allen Curran, Kirsten De Beurs
Quantifying Exceptionally Large Populations Of Acropora Spp. Corals Off Belize Using Sub-Meter Satellite Imagery Classification, James Busch, Lisa Greer, David Harbor, Karl Wirth, Halard Lescinsky, H. Allen Curran, Kirsten De Beurs
Geosciences: Faculty Publications
Caribbean coral reefs have experienced dramatic declines in live coral cover in recent decades. Primary branching framework Caribbean corals, Acropora cervicornis (Lamarck, 1816) and Acropora palmata (Lamarck, 1816), have suffered the greatest collapse. Coral Gardens, Belize, is one of few remaining, and perhaps the largest, refugia for abundant, healthy, but undocumented populations of both Acropora species in the Caribbean Sea. In the present study, GeoEye-1 multispectral satellite imagery of a 25 km2 reefal area near Ambergris Caye, Belize, was analyzed to identify live Acropora spp. cover. We used a supervised classification to predict occurrence of areas with live Acropora spp. …
Modern And Fossil Callianassid Burrows Of The Bahamas: Comparisons And Implications For Paleoenvironmental Analysis, H. Allen Curran, Koji Seike
Modern And Fossil Callianassid Burrows Of The Bahamas: Comparisons And Implications For Paleoenvironmental Analysis, H. Allen Curran, Koji Seike
Geosciences: Faculty Publications
Reprinted from: Bosiljka Glumac & Michael Savarese (eds.), Proceedings of the 16th Symposium on the Geology of the Bahamas and Other Carbonate Regions:San Salvador, Gerace Research Center
Subaerial Seeps On Holocene Carbonate Eolian Strata From Cat Island, Bahamas, Bosiljka Glumac, H. Allen Curran, Sarah Brisson
Subaerial Seeps On Holocene Carbonate Eolian Strata From Cat Island, Bahamas, Bosiljka Glumac, H. Allen Curran, Sarah Brisson
Geosciences: Faculty Publications
Reprinted from: Bosiljka Glumac & Michael Savarese (eds.),Proceedings of the 16th Symposium of the Geology of the Bahamas and Other Carbonate Regions: San Salvador, Gerace Research Center
Origin Of Late Holocene Strandplains In The Southern Exuma Islands, Bahamas: Progradation, Ephemeral Highstands, And Storminess, Michael Savarese, H. Allen Curran
Origin Of Late Holocene Strandplains In The Southern Exuma Islands, Bahamas: Progradation, Ephemeral Highstands, And Storminess, Michael Savarese, H. Allen Curran
Geosciences: Faculty Publications
Reprinted from: Bosiljka Glumac & Michael Savarese (eds.), Proceedings of the16th Symposium on the Geology of the Bahamas and Other Carbonate Regions:San Salvador, Gerace Research Center