A5037678096- Seismic Waves and Analysis
- earthquake and tectonic studies
- Seismic Imaging and Inversion Techniques
- High-pressure geophysics and materials
- Geological and Geochemical Analysis
- Geological and Geophysical Studies
- Seismology and Earthquake Studies
- Geophysical and Geoelectrical Methods
- Methane Hydrates and Related Phenomena
- Geological Studies and Exploration
- Hydrocarbon exploration and reservoir analysis
- Earthquake Detection and Analysis
- Geophysics and Sensor Technology
- Geophysical Methods and Applications
- Geological formations and processes
- Geochemistry and Geologic Mapping
- Hydraulic Fracturing and Reservoir Analysis
- Marine and environmental studies
- Reservoir Engineering and Simulation Methods
- Drilling and Well Engineering
- Underwater Acoustics Research
- Geology and Paleoclimatology Research
- Geological and Tectonic Studies in Latin America
- Climate change and permafrost
- Landslides and related hazards
GFZ Helmholtz Centre for Geosciences
2015-2024
University of Potsdam
2015
California State University Los Angeles
2001
University of Wisconsin–Madison
2001
California Department of Parks and Recreation
1999
California Department of Transportation
1999
California State University, Northridge
1999
Geological Survey of Denmark and Greenland
1999
Karlsruhe Institute of Technology
1999
Southern California Earthquake Center
1999
Natural hazard prediction and efficient crust exploration require dense seismic observations both in time space. Seismological techniques provide ground-motion data, whose accuracy depends on sensor characteristics spatial distribution. Here we demonstrate that dynamic strain determination is possible with conventional fibre-optic cables deployed for telecommunication. Extending recently distributed acoustic sensing (DAS) studies, present high resolution spatially un-aliased broadband data....
The receiver function method (RFM) is a commonly used technique to study the crustal and upper mantle velocity structure. Early (RF) investigations were performed mostly at individual permanent stations. They focused on structures, later discontinuities (410 km 660 discontinuities). Only recently has research been directed towards of lateral (2- 3-D) variability major boundaries in crust by arrays using temporary permanent, three-component, short-period broad-band seismic To improve...
To address one of the central questions plate tectonics—How do large transform systems work and what are their typical features?—seismic investigations across Dead Sea Transform (DST), boundary between African Arabian plates in Middle East, were conducted for first time. A major component these was a combined reflection/refraction survey territories Palestine, Israel Jordan. The main results this study are: (1) seismic basement is offset by 3–5 km under DST, (2) DST cuts through entire...
A seismic reflection and refraction survey across the San Andreas Fault (SAF) near Parkfield provides a detailed characterization of crustal structure location Observatory at Depth (SAFOD). Steep‐dip prestack migration frequency domain acoustic waveform tomography were applied to obtain highly resolved images upper 5 km crust for 15 on either side SAF. The resulting velocity model constrains top Salinian granite with great detail. show several strong‐amplitude vertical reflectors in...
For the first time, ambient noise tomography is used to clearly image magma chamber beneath Lake Toba caldera, one of largest Quaternary calderas on Earth. Using data from 40 seismic stations deployed between May and October 2008 around Toba, empirical Green's functions are extracted long term cross‐correlations continuous records. These dominated by Rayleigh waves, whose group velocities can be measured in period range 2.5 12 seconds. Arrival times these waves picked for a given inverted...
We examine a 24‐hour period of active San Andreas Fault (SAF) tremor and show that this is largely composed repeated similar events. Utilizing similarity, we locate the subset with waveforms to an identified low frequency earthquake (LFE) “master template,” located using P S wave arrivals be ∼26 km deep. To compensate for signal‐to‐noise, estimate event‐pair differential times at “clusters” nearby stations rather than single stations. find locations form near‐linear structure in map view,...
Research Article| December 01, 2011 DEEP CRUSTAL PROFILE ACROSS THE SOUTHERN KAROO BASIN AND BEATTIE MAGNETIC ANOMALY, SOUTH AFRICA: AN INTEGRATED INTERPRETATION WITH TECTONIC IMPLICATIONS A. LINDEQUE; LINDEQUE Alfred Wegener Institute for Polar and Marine Research, Am Alten Hafen 26, 27568 Bremerhaven, Germany, Africa Earth Observatory Network Faculty of Science, Nelson Mandela Metropolitan University, 6031 Port Elizabeth, South Africa, Council Geoscience, Western Cape, P.O. Box 572, 7535...
Research Article| January 01, 2001 Crustal structure and tectonics from the Los Angeles basin to Mojave Desert, southern California G.S. Fuis; Fuis 1U.S. Geological Survey, 345 Middlefield Road, MS 977, Menlo Park, 94025, USA Search for other works by this author on: GSW Google Scholar T. Ryberg; Ryberg 2GeoForschungsZentrum, Telegrafenberg, 14473 Potsdam, Germany N.J. Godfrey; Godfrey 3University of Southern California, Angeles, 90089-0740, D.A. Okaya; Okaya J.M. Murphy 4U.S. Geology (2001)...
Short‐period, three‐component recordings of the seismic wave field Peaceful Nuclear Explosions (PNEs) on long‐range profiles are used to determine fine structure mantle lithosphere. By analyzing frequency content recorded phases and applying different band‐pass filters data, it is possible divide into two distinctly constituents: low‐frequency body waves traveling along Fermat paths (first arrivals) high‐frequency teleseismic (or long‐range) P n phase with a group velocity 8.1 km/s...
Magnetotelluric and seismic methods provide complementary information about the resistivity velocity structure of subsurface on similar scales resolutions. No global relation, however, exists between these parameters, correlations are often valid for only a limited target area. Independently derived inverse models from can be combined using classification approach to map geologic structure. The method employed is based solely statistical correlation physical properties in joint parameter...
Fault zones are the locations where motion of tectonic plates, often associated with earthquakes, is accommodated. Despite a rapid increase in understanding faults last decades, our knowledge their geometry, petrophysical properties, and controlling processes remains incomplete. The central questions addressed here study Dead Sea Transform (DST) Middle East as follows: (1) What structure kinematics large fault zone? (2) controls its kinematics? (3) How does DST compare to other plate...
Upwelling hot mantle plumes are thought to disintegrate continental lithosphere and considered be drivers of active breakup. The formation the Walvis Ridge during opening South Atlantic is related a putative plume-induced We investigated crustal structure (southeast Ocean) at its intersection with margin searched for anomalies possible plume head. overall we identify suggests that no broad head existed anomalous melting occurred only locally. therefore question importance as driver breakup...
The San Andreas fault (SAF) is one of the most studied strike-slip faults in world; yet its subsurface geometry still uncertain locations.The Salton Seismic Imaging Project (SSIP) was undertaken to image structure surrounding SAF and also geometry.We present SSIP studies at two locations Coachella Valley northern trough.On our line 4, a fault-crossing profile just north Sea, sedimentary basin depth reaches 4 km southwest SAF.On 6, end Valley, ∼2-3 centered on central, active trace...
An interdisciplinary approach is needed to fully understand the formation and evolution of Earth’s crust. Different disciplines (geology, geophysics, geochemistry, etc.) provide complementary information that cover different depth time scales. By combining this information, a better understanding crustal processes becomes possible. Seismic methods, for example, are utilized obtain structural images present state crust derive its petrophysical properties. This knowledge can then be...
Residues of industrial mining activities like rock waste, tailings, and stockpiles are amongst the largest human-made structures in both area volume. In case tailings dams, risk posed by failure is well documented has led to implementation regulatory standards. As one measures reduce potential harm environment people, Global Industry Standard on Tailings Managment (GISTM) implemented UNEP 2020 proposes installation "monitoring systems manage at all phases facility lifecycle". This objectives...
A striking feature of Russian long-range seismic refraction data from Peaceful Nuclear Explosions is the observation a high-frequency teleseismic Pn, phase, which travels with group velocity 8.0 km s-1 out to distances several thousands kilometres. Modelling using reflectivity method shows that this phase can be understood as response an upper mantle contains random RMS fluctuations about ±4 per cent superimposed on positive gradient. This class model explains existence its content and coda...
Research Article| February 01, 2003 Fault systems of the 1971 San Fernando and 1994 Northridge earthquakes, southern California: Relocated aftershocks seismic images from LARSE II Gary S. Fuis; Fuis 1Earthquakes Hazards Team, U.S. Geological Survey, Menlo Park, California 94025, USA Search for other works by this author on: GSW Google Scholar Robert W. Clayton; Clayton 2Seismological Laboratory, Institute Technology, Pasadena, 91125, Paul M. Davis; Davis 3Department Earth Space Sciences,...
Abstract Permafrost inundated since the last glacial maximum is degrading, potentially releasing trapped or stabilized greenhouse gases, but few observations of depth ice‐bonded permafrost (IBP) below seafloor exist for most arctic continental shelf. We use spectral ratios ambient vibration seismic wavefield, together with estimated shear wave velocity from dispersion curves surface waves, estimating thickness sediment overlying IBP. Peaks in modeled three‐layered 1‐D systems correspond...
Abstract A two-dimensional velocity structure for the mantle down to a depth of 700 km derived from super long-range nuclear explosion seismic data recorded along Quartz profile in northern Eurasia is presented. The extends Russian Platform, across Western Siberia Altai mountains. detailed structural image lithosphere and asthenosphere shows strong lateral variations profile. subcrustal 100 characterized by P-wave between 7.7 8.7 km/sec. are consistent with Ural mountains having crustal...
Dynamic processes at sheared margins associated with the formation of sedimentary basins and marginal ridges are poorly understood. The southern African margin provides an excellent opportunity to investigate deep crustal structure a transform characterize acting these by studying Agulhas‐Falkland Fracture Zone, Outeniqua Basin, Diaz Marginal Ridge. To do this, we present results combined seismic land‐sea experiments Agulhas‐Karoo Geoscience Transect. Detailed velocity‐depth models show...