A5077926083- Methane Hydrates and Related Phenomena
- earthquake and tectonic studies
- Spacecraft and Cryogenic Technologies
- Seismic Imaging and Inversion Techniques
- Geological and Geochemical Analysis
- Offshore Engineering and Technologies
- Geological and Geophysical Studies
- Astro and Planetary Science
- Seismic Waves and Analysis
- High-pressure geophysics and materials
- Astronomical Observations and Instrumentation
- Geological Modeling and Analysis
- Hydrocarbon exploration and reservoir analysis
- Planetary Science and Exploration
- Geological and Tectonic Studies in Latin America
- Atmospheric Ozone and Climate
- Geomagnetism and Paleomagnetism Studies
- Scientific Research and Discoveries
- Geological formations and processes
- Underwater Vehicles and Communication Systems
- Geophysics and Gravity Measurements
- Geology and Paleoclimatology Research
- Geological and Geophysical Studies Worldwide
- Atmospheric and Environmental Gas Dynamics
- Inertial Sensor and Navigation
The University of Texas at Austin
2016-2025
University of Texas Institute for Geophysics
2020-2023
Expedition (United Kingdom)
2019
International Ocean Discovery Program
2019
Lamont-Doherty Earth Observatory
2013-2018
Columbia University
2014-2018
Slow slip events (SSEs) accommodate a significant proportion of tectonic plate motion at subduction zones, yet little is known about the faults that actually host them. The shallow depth (<2 km) well-documented SSEs Hikurangi zone offshore New Zealand offers unique opportunity to link geophysical imaging with direct access incoming material represents megathrust fault rocks hosting slow slip. Two recent International Ocean Discovery Program Expeditions sampled this before it entrained...
Abstract We present prestack time‐migrated multichannel seismic images along two cross‐plate transects from the Juan de Fuca (JdF) Ridge to Cascadia deformation front (DF) offshore Oregon and Washington which we characterize crustal structure, distribution extent of faults across plate interior as crust ages near DF in response subduction bending. Within interior, observe numerous small offset sediment section beginning 50–70 km ridge axis with sparse fault plane reflections confined upper...
The origin of rupture segmentation along subduction zone megathrusts and linkages to the structural evolution are poorly understood. Here, regional-scale seismic imaging Cascadia margin is used characterize megathrust spanning ~900 km from Vancouver Island California border, across seismogenic a few tens kilometers coast. Discrete domains in lower plate geometry sediment underthrusting identified, not evident prior regional models, which align with changes lithology structure upper...
Abstract We report results from a wide‐angle controlled source seismic experiment across the Juan de Fuca plate designed to investigate evolution of accretion at ridge subduction Cascadia margin. A two‐dimensional velocity model crust and upper mantle is derived joint reflection‐refraction traveltime inversion. To interpret our tomography results, we first generate plausible baseline model, assuming cooling realistic oceanic lithologies. then use an effective medium theory infer extent...
Abstract Oceanic plate seamounts are believed to play an important role in megathrust rupture at subduction zones, although consistent relationships between subducting and interface seismicity patterns not found. While most studies focus on impacts linked their topography, also sites of heterogeneity incoming sediments that may contribute properties. Here, we characterize along the Cascadia zone using new high‐resolution seismic images compressional wave ( V p ) models from CASIE21...
Abstract Submarine magmatism and associated hydrothermal fluid flows has significant feedback influence on the petroleum geology of sedimentary basins. This study uses new seismic profiles multibeam bathymetric data to examine morphology internal architecture post‐seafloor spreading magmatic structures, especially volcanoes Xisha uplift, in extensive detail. We discover for first time systems derived from northwestern South China Sea. Numerous solitary volcanic groups occur uplift produce...
Abstract The south central Chilean margin regularly produces many of the world's largest earthquakes and tsunami, including 2010 Mw 8.8 Maule 1960 9.5 Valdivia events. In 2017, we acquired seismic reflection data along ~1,000 km using R/V Langseth 's 15 long receiver array 108.2 l (6,600 in 3 ) source to image structures associated with these ruptures. We focus on segment coseismic slip (~40 m). outer 40 forearc is an accretionary wedge constructed primarily stacked sedimentary packages...
Recurring slow slip along near-trench megathrust faults occurs at many subduction zones, but for unknown reasons, this process is not universal. Fluid overpressures are implicated in encouraging slip; however, links between slip, fluid content, and hydrogeology remain poorly known natural systems. Three-dimensional seismic imaging ocean drilling the Hikurangi margin reveal a widespread previously reservoir within extensively hydrated (up to 47 vol % H2O) volcanic upper crust of subducting...
Abstract We present a catalog of offshore seismicity generated from Cascadia Initiative (CI) ocean‐bottom seismometer data. Earthquakes were detected within the CI data using short‐time‐average/long‐time‐average trigger and located 1‐D velocity models developed seismic reflection/refraction surveys. The catalog, which contains 271 earthquakes with magnitude 0.4–4.0 along coasts Vancouver Island, Washington, Oregon, Northern California, spans all 4 years ocean bottom deployment shows distinct...
Abstract The Pāpaku Fault Zone, drilled at International Ocean Discovery Program (IODP) Site U1518, is an active splay fault in the frontal accretionary wedge of Hikurangi Margin. In logging‐while‐drilling data, 33‐m‐thick zone exhibits mixed modes deformation associated with a trend downward decreasing density, P ‐wave velocity, and resistivity. Methane hydrate observed from ~30 to 585 m below seafloor (mbsf), including within surrounding zone. Hydrate accumulations are vertically...
Abstract To characterize the along‐strike structural variations of Juan de Fuca (JdF) Plate as it enters Cascadia subduction zone, we present prestack time migrated multichannel seismic reflection images JdF along a 400‐km‐long trench‐parallel transect extending from 44.3°N to 47.8°N. Beneath 1.8–3.0‐km‐thick sediment cover, our data reveal basement topographic anomalies associated with 1.2‐km‐high seamount and in vicinity propagator wakes (390–540‐m relief). Weak Moho reflections are imaged...
Abstract P ‐to‐ S ‐converted waves observed in controlled‐source multicomponent ocean bottom seismometer (OBS) records were used to derive the Vp / Vs structure of Cascadia Basin sediments. We converted at basement an empirical function describing average sediments as a sediment thickness. derived one‐dimensional interval functions from semblance velocity analysis intrasediment and reflections, which we define versus burial depth compaction trend. find that seaward deformation front,...