Earth Science
Recent Submissions
-
Pore water geochemistry along continental slopes north of the East Siberian Sea: inference of low methane concentrations
(2017)Continental slopes north of the East Siberian Sea potentially hold large amounts of methane (CH4) in sediments as gas hydrate and free gas. Although release of this CH4 to the ocean and atmosphere has become a topic of ... -
Airborne radar sounding evidence for deformable sediments and outcropping bedrock beneath Thwaites Glacier, West Antarctica
(2014)The geologic and morphologic records of prior ice sheet configurations show evidence of rapid, back-stepping, meltwater intensive retreats. However, the potential for such a retreat in a contemporary glacier depends on the ... -
Aged black carbon in marine sediments and sinking particles
(2014)We report measurements of oceanic black carbon (BC) to determine the sources of BC to abyssal marine sediments in the northeast Pacific Ocean. We find that the average 14C age of BC is older (by 6200 ± 2200 14C years) than ... -
Regional background O3 and NOx in the Houston–Galveston–Brazoria (TX) region: a decadal-scale perspective
(2017)Ozone (O3) in the lower troposphere is harmful to people and plants, particularly during summer, when photochemistry is most active and higher temperatures favor local chemistry. Local precursor emissions, such as those ... -
Optimal Convergence Rates Results for Linear Inverse Problems in Hilbert Spaces
(2016)In this article, we prove optimal convergence rates results for regularization methods for solving linear ill-posed operator equations in Hilbert spaces. The results generalizes existing convergence rates results on ... -
Joint inversion of receiver functions and surface waves with enhanced preconditioning on densely distributed CNDSN stations: Crustal and upper mantle structure beneath China
(2016)We present shear wave velocity structure beneath China by joint modeling of teleseismic receiver function and Rayleigh wave group velocity dispersion data observed at +1000 permanent broadband seismic stations in the Chinese ... -
Measurement of Rayleigh wave ellipticity and its application to the joint inversion of high-resolutionﾠSwave velocity structure beneath northeast China
(2016)We present a new 3-D S wave velocity model of the northeast (NE) China from the joint inversion of the Rayleigh wave ellipticity and phase velocity at 8–40 s periods. Rayleigh wave ellipticity, or Rayleigh wave Z/H (vertical ... -
Isotopic ordering in atmospheric O2 as a tracer of ozone photochemistry and the tropical atmosphere
(2016)The distribution of isotopes within O2 molecules can be rapidly altered when they react with atomic oxygen. This mechanism is globally important: while other contributions to the global budget of O2 impart isotopic signatures, ... -
Effect of melt composition on crustal carbonate assimilation: Implications for the transition from calcite consumption to skarnification and associated CO2 degassing
(2016)Skarns are residue of relatively low-temperature magma-induced decarbonation in the crust largely associated with silicic plutons. Mafic magmatic intrusions are also capable of releasing excess CO2 due to carbonate ... -
Scaling relationships and physics for mixed heating convection in planetary interiors: Isoviscous spherical shells
(2016)We use a suite of 3-D numerical experiments to test and expand 2-D planar isoviscous scaling relationships of Moore (2008) for mixed heating convection in spherical geometry mantles over a range of Rayleigh numbers (Ra). ... -
The energetics and convective vigor of mixed-mode heating: Velocity scalings and implications for the tectonics of exoplanets
(2016)The discovery of large terrestrial (~1 Earth mass (Me) to < 10 Me) extrasolar planets has prompted a debate as to the likelihood of plate tectonics on these planets. Canonical models assume classic basal heating scaling ... -
Crustal structure and deformation beneath the NE margin of the Tibetan plateau constrained by teleseismic receiver function data
(2016)We analysed a large amount of teleseismic receiver function data recorded by 172 broadband stations in the NE Tibetan plateau and its surrounding areas to investigate the crustal velocity and anisotropy structure beneath ... -
Inverse Boundary Value Problem For The Helmholtz Equation: Quantitative Conditional Lipschitz Stability Estimates
(2016)We study the inverse boundary value problem for the Helmholtz equation using the Dirichlet-to-Neumann map at selected frequencies as the data. A conditional Lipschitz stability estimate for the inverse problem holds in the ... -
Application of Frequency-dependent Traveltime Tomography and Full Waveform Inversion to Realistic Near-surface Seismic Refraction Data
(2016)We present a synthetic test that uses a workflow consisting of a new frequency-dependent traveltime tomography (FDTT) method to provide a starting model for full waveform inversion (FWI) for near-surface seismic velocity ... -
Dynamic simulations of potential methane release from East Siberian continental slope sediments
(2016)Sediments deposited along continental margins of the Arctic Ocean presumably host large amounts of methane (CH4) in gas hydrates. Here we apply numerical simulations to assess the potential of gas hydrate dissociation and ... -
Continental hyperextension, mantle exhumation, and thin oceanic crust at the continent-ocean transition, West Iberia: New insights from wide-angle seismic
(2016)Hyperextension of continental crust at the Deep Galicia rifted margin in the North Atlantic has been accommodated by the rotation of continental fault blocks, which are underlain by the S reflector, an interpreted detachment ... -
The importance of temporal stress variation and dynamic disequilibrium for the initiation of plate tectonics
(2016)We use 1-D thermal history models and 3-D numerical experiments to study the impact of dynamic thermal disequilibrium and large temporal variations of normal and shear stresses on the initiation of plate tectonics. Previous ... -
Past ice-sheet behaviour: retreat scenarios and changing controls in the Ross Sea, Antarctica
(2016)Studying the history of ice-sheet behaviour in the Ross Sea, Antarctica's largest drainage basin can improve our understanding of patterns and controls on marine-based ice-sheet dynamics and provide constraints for numerical ... -
In situ stress magnitude and rock strength in the Nankai accretionary complex: a novel approach using paired constraints from downhole data in two wells
(2016)We present a method to simultaneously constrain both far-field horizontal stress magnitudes (S hmin and S Hmax) and in situ rock unconfined compressive strength (UCS), using geophysical logging data from two boreholes ... -
Thermal Treatment of Hydrocarbon-Impacted Soils: A Review of Technology Innovation for Sustainable Remediation
(2016)Thermal treatment technologies hold an important niche in the remediation of hydrocarbon-contaminated soils and sediments due to their ability to quickly and reliably meet cleanup standards. However, sustained high temperature ...
RSS 1.0