A5020755982- earthquake and tectonic studies
- Earthquake Detection and Analysis
- Geological and Geochemical Analysis
- High-pressure geophysics and materials
- Seismology and Earthquake Studies
- Geological and Geophysical Studies
- Synthetic Aperture Radar (SAR) Applications and Techniques
- Seismic Waves and Analysis
- Geophysics and Gravity Measurements
- Landslides and related hazards
- Geochemistry and Geologic Mapping
- Geological Studies and Exploration
- Seismic Imaging and Inversion Techniques
- Geotechnical and Geomechanical Engineering
- GNSS positioning and interference
- Flood Risk Assessment and Management
- Geological Modeling and Analysis
- Coastal and Marine Dynamics
- Fluid Dynamics Simulations and Interactions
- Geophysics and Sensor Technology
- Inertial Sensor and Navigation
- Earthquake and Tsunami Effects
- Hydrology and Sediment Transport Processes
- Drilling and Well Engineering
- Geological and Tectonic Studies in Latin America
University of New Mexico
2021-2025
Earth Observatory of Singapore
2015-2022
Nanyang Technological University
2016-2022
University of California, San Diego
2010-2016
Scripps Institution of Oceanography
2012-2016
University of Missouri
2013
Detailed geodetic imaging of earthquake ruptures enhances our understanding physics and associated ground shaking. The 25 April 2015 moment magnitude 7.8 in Gorkha, Nepal was the first large continental megathrust rupture to have occurred beneath a high-rate (5-hertz) Global Positioning System (GPS) network. We used GPS interferometric synthetic aperture radar data model as slip pulse ~20 kilometers width, ~6 seconds duration, with peak sliding velocity 1.1 meters per second, which...
Abstract Interferometric synthetic aperture radar (InSAR) is a key tool for the analysis of displacement and stress changes caused by large crustal earthquakes, particularly in remote areas. A challenge traditional InSAR has been its limited spatial temporal coverage especially very events, whose dimensions exceed typical swath width 70–100 km. This problem addressed ALOS‐2 satellite, PALSAR‐2 instrument operates ScanSAR mode, enabling repeat time 2 weeks 350 Here we present line‐of‐sight...
We use high resolution interferometric synthetic aperture radar and GPS measurements of crustal motion across the southern San Andreas Fault system to investigate effects elastic heterogeneity fault geometry on inferred slip rates locking depths. Geodetically measured strain are asymmetric with respect mapped traces both Jacinto faults. Two possibilities have been proposed explain this observation: large contrasts in rigidity faults, or an alternate such as a dipping blind segment Fault....
Abstract Assessment of seismic hazard relies on estimates how large an area a tectonic fault could potentially rupture in single earthquake. Vital information for these forecasts includes which areas are locked and the is segmented. Much research has focused exploring downdip limits to from chemical thermal boundaries, along-strike barriers subducted structural features, yet we regularly see only partial fully patches that have ruptured as whole larger Here draw insight into this conundrum...
Abstract We investigate the spatial pattern of surface creep and off‐fault deformation along southern segment San Andreas Fault using a combination multiple interferometric synthetic aperture radar viewing geometries survey‐mode GPS occupations dense array crossing fault. Radar observations from Envisat during period 2003–2010 were used to separate horizontal vertical motion, providing high‐resolution image uplift shallow fault trace. The data reveal pervasive southernmost 50 km Creep is...
Crustal rock strength from outer space The response of crustal to stresses is challenging estimate yet vital for determining risks events such as earthquakes. Moore et al. take advantage the recent M w 7.1 Kumamoto earthquake in Japan determine rheology rocks region. observed inversion strain rates demonstrates that certain areas have stiff and others (e.g., under Aso volcanic complex) much weaker rock. results match up with expectations, which means method can successfully measure...
Abstract The Rakhine (Arakan)‐Bangladesh megathrust, along which the Indian and Burma plates collide, is assumed by some to be inactive/aseismic due lack of notable interplate earthquakes in modern instrumental catalog. However, geological historical evidence great 1762 Arakan earthquake suggest megathrust can produce M ~8 events that could adversely affect lives millions people region. To investigate seismogenic potential determine slip budget we first need solve for India‐Burma‐Sunda...
Abstract Geologic reconstructions of the Main Himalayan Thrust in Nepal show a laterally extensive midcrustal ramp, hypothesized to form downdip boundary interseismic locking. Using recent compilation GPS velocities and simplified model fault coupling, we estimate width coupling across using series two‐dimensional transects. We find that increases smoothly from 70 90 km eastern 100–110 central Nepal, then narrows again western Nepal. The inferred transition is closely aligned with geologic...
Abstract The updip limit of the seismogenic zone megathrusts is poorly understood. relative absence observed microseismicity in such regions, together with laboratory studies friction, suggests that shallow fault mostly velocity strengthening, and likely to creep. Inversions geodetic data commonly show low zero coupling at trench, reinforcing this view. We locked, downdip portion megathrust creates an stress shadow prevents from creeping a significant rate, regardless its frictional...
Abstract The Indo‐Burma subduction zone is a highly oblique system where the Indian plate converging with Eurasian plate. How strain partitioned between interface and upper Kabaw Fault, whether megathrust locked active of convergence that can generate great earthquakes are ongoing debates. Here, we use data from total 68 Global Navigation Satellite System (GNSS) stations, including newly installed stations across Fault compute an updated horizontal vertical GNSS velocity field. We correct...
Abstract We analyze a suite of geodetic observations across the Imperial Fault in southern California that span all parts earthquake cycle. Coseismic and postseismic surface slips due to 1979 M 6.6 Valley were recorded with trilateration alignment surveys by Harsh (1982) Crook et al. (1982), interseismic deformation is measured using combination multiple interferometric synthetic aperture radar (InSAR)‐viewing geometries continuous survey‐mode GPS. In particular, we combine more than 100 GPS...
Discrepancies between geodetically and geologically estimated thrust fault slip rates are generally viewed as a methodological problem. Even when rate is steady over geological time, discrepancy may exist because each method sensitive to different deformation processes. However, this offers tool estimate the partitioning of convergence footwall hanging wall deformation, therefore way discriminate among orogenic styles. Here we investigate one such for Shillong Plateau, basement-cored...
The active tectonics of the Myanmar (formerly Burma) microplate in central are caused by oblique collision between Sunda and Eurasia plates to east Indian plate west. kinematics this boundary zone remain a subject controversy, due part limited geodetic seismic observations region. Here, we report 41 new 67 updated survey-mode continuous Global Navigation Satellite System (GNSS) velocities spanning western Myanmar, 15 – 23°N 93 98°E. For first time, our network allows us directly observe...
To better quantify the relatively long period (< 0.3 Hz) shaking experienced during 2015 Gorkha (Nepal) earthquake sequence, we study finite rupture processes and associated 3D ground motion of Mw7.8 mainshock Mw7.2 aftershock. The synthetics are then used in broadband Kathmandu with a hybrid approach, summarized companion paper (Chen Wei, 2017, submitted together). We determined coseismic process by joint inversion InSAR/SAR, GPS (static high-rate), strong teleseismic waveforms. Our for...
The M w 6.0 Mt. Kinabalu earthquake of 2015 was a complete (and deadly) surprise, because it occurred well away from the nearest plate boundary in region very low historical seismicity. Our seismological, space geodetic, geomorphological, and field investigations show that resulted rupture northwest-dipping normal fault did not reach surface. Its unilateral almost directly beneath 4000-m-high triggered widespread slope failures on steep mountainous slopes, which included rockfalls killed 18...
Abstract The 25 February 2008 M w 7.2 North Pagai earthquake partially ruptured the middle section of Mentawai patch Sunda megathrust, offshore Sumatra. has been forecast to generate a great in next few decades. However, current cycle so far broken sequence partial ruptures, one which was event, illustrating potential spectrum sizes. We estimate coseismic slip distribution event by jointly inverting offsets from GPS and interferometric synthetic aperture radar. then afterslip with 5.6 years...
Abstract We present geodetically derived coseismic slip models for four M w ~6 strike‐slip earthquakes that struck the mainland island of Sumatra, Indonesia, between 2007 and 2016. Three these ruptured segments Sumatran Fault Zone: 6.3 6.4 Lake Singkarak doublet, 2009 6.6 Dikit event. The fourth earthquake, 2016 Pidie Jaya event, an unmapped active fault in a region historically low seismicity near northern coast Aceh. Our results suggest (1) estimated rupture extents doublet event were...
Abstract A series of four Mw&gt;6 earthquakes struck the northern region Lombok, eastern Indonesia, in a span three weeks from late July to mid-August 2018. The was thought be associated with Flores thrust, but exact mechanism causing unusual earthquake has remained elusive. Our Interferometric Synthetic Aperture Radar analysis, combined insights seismology, indicates that events originated at different hypocenter depths differing fault geometries, which may explain cascading behavior...