Zha, Y., S. C. Webb, S. S. Wei, D. A. Wiens, D. K. Blackman, W
... to ∼95 mm/yr and the distance from the ridge to the volcanic arc increases from about 40 km to 100 km (Zellmer and Taylor, 2001). Crustal thickness decreases from 8–9 km at the central ELSC and Valu Fa Ridge (VFR) to 6–7 km at the northern ELSC (Arai and Dunn, 2014; Crawford et al., 2003; Jacobs et ...
... to ∼95 mm/yr and the distance from the ridge to the volcanic arc increases from about 40 km to 100 km (Zellmer and Taylor, 2001). Crustal thickness decreases from 8–9 km at the central ELSC and Valu Fa Ridge (VFR) to 6–7 km at the northern ELSC (Arai and Dunn, 2014; Crawford et al., 2003; Jacobs et ...
Regionality of deep low-frequency earthquakes associated with
... occurred at depths of about 50 km beneath eastern Kyushu. Although there are high-frequency components, the amplitudes of 2–8 Hz are dominant relative to those of higher-frequency ranges, and the onset of the P wave is not clear. Similar results were found for the corresponding east–west (EW) compon ...
... occurred at depths of about 50 km beneath eastern Kyushu. Although there are high-frequency components, the amplitudes of 2–8 Hz are dominant relative to those of higher-frequency ranges, and the onset of the P wave is not clear. Similar results were found for the corresponding east–west (EW) compon ...
Earthquakes
... mantle. Eventually the plate heats up enough deform plastically and earthquakes stop. Convergent plate boundaries produce earthquakes all around the Pacific Ocean basin. The Philippine Plate and the Pacific Plate subduct beneath Japan, creating a chain of volcanoes and as many as 1,500 earthquakes ann ...
... mantle. Eventually the plate heats up enough deform plastically and earthquakes stop. Convergent plate boundaries produce earthquakes all around the Pacific Ocean basin. The Philippine Plate and the Pacific Plate subduct beneath Japan, creating a chain of volcanoes and as many as 1,500 earthquakes ann ...
The strength of faults in the crust in the western
... modifications to strength-controlling parameters, with the understanding that global parameters remain unchanged throughout the entire set of simulations. SHELLS uses a grid of spherical triangles for the continuum elements, and arcs of great circle for the fault elements (Kong and Bird, 1995). To dr ...
... modifications to strength-controlling parameters, with the understanding that global parameters remain unchanged throughout the entire set of simulations. SHELLS uses a grid of spherical triangles for the continuum elements, and arcs of great circle for the fault elements (Kong and Bird, 1995). To dr ...
Some Geology Basics
... Sedimentary rocks make up only a small percentage of the crust, but sediments and sedimentary rocks cover most of the planet’s surfaces and sea floor. Sedimentary rocks may contain some of the igneous rock-forming minerals (especially quartz), but the process of weathering tends to break the mineral ...
... Sedimentary rocks make up only a small percentage of the crust, but sediments and sedimentary rocks cover most of the planet’s surfaces and sea floor. Sedimentary rocks may contain some of the igneous rock-forming minerals (especially quartz), but the process of weathering tends to break the mineral ...
The Subductability of Continental Lithosphere
... and a deep (less depleted) lithospheric mantle. The oceanic domain is composed of a thin layer of pelagic sediments, a basaltic upper crust, a gabbroic lower crust, a depleted shallow lithospheric mantle, and a deep (less depleted) lithospheric mantle. The reference passive margin includes some lay ...
... and a deep (less depleted) lithospheric mantle. The oceanic domain is composed of a thin layer of pelagic sediments, a basaltic upper crust, a gabbroic lower crust, a depleted shallow lithospheric mantle, and a deep (less depleted) lithospheric mantle. The reference passive margin includes some lay ...
Plate Tectonics Questions
... 45. During which geologic period were the continents all part of one landmass, with North America and South America joined to Africa? A) Tertiary C) Triassic ...
... 45. During which geologic period were the continents all part of one landmass, with North America and South America joined to Africa? A) Tertiary C) Triassic ...
What Are Seismic Waves?
... Seismic waves are the waves of energy caused by the sudden breaking of rock within the earth or an explosion. They are the energy that travels through the earth and is recorded on seismographs. ...
... Seismic waves are the waves of energy caused by the sudden breaking of rock within the earth or an explosion. They are the energy that travels through the earth and is recorded on seismographs. ...
Seismic wave propagation concepts applied to the interpretation of
... that the propagation velocity is higher in the lower layer than in the upper layer. The direct contribution from the source to the receiver is trivial and is not part of the ensuing discussion. Thus, due to the type of velocity contrast, there will be a critical angle as derived by Snell’s law. The ...
... that the propagation velocity is higher in the lower layer than in the upper layer. The direct contribution from the source to the receiver is trivial and is not part of the ensuing discussion. Thus, due to the type of velocity contrast, there will be a critical angle as derived by Snell’s law. The ...
Shear-wave statics using receiver functions
... The receiver function method is a well-known seismological method to investigate the structure of the earth’s crust and upper mantle. It relies on the observation of shear-waves in the coda of a teleseismic P-wave resulting from mode conversion of the P-wave at major crustal or upper-mantle disconti ...
... The receiver function method is a well-known seismological method to investigate the structure of the earth’s crust and upper mantle. It relies on the observation of shear-waves in the coda of a teleseismic P-wave resulting from mode conversion of the P-wave at major crustal or upper-mantle disconti ...
B. Measurement of Seismic Wave
... There are two kinds of discharge modes in our experiment, corona discharge and arc discharge, shown in Fig.5. The curve 1-3 are current waveforms and the curve 4 is the triggering signal waveform. The three current waveforms were the measurement results in three different elements in the array. The ...
... There are two kinds of discharge modes in our experiment, corona discharge and arc discharge, shown in Fig.5. The curve 1-3 are current waveforms and the curve 4 is the triggering signal waveform. The three current waveforms were the measurement results in three different elements in the array. The ...
Tectonic evolution and deep to shallow geometry of Nagamachi-Rifu Hiroshi Sato
... Kitamura, N. (Ed.), Cenozoic Arc Terrane of Northeast Honshu, Japan, 3 vols., Hobundo, Sendai, Japan, 1986 (in Japanese). Kitamura, N., T. Ishii, A. Sangawa, and H. Nakagawa, Geology of the Sendai district, with Geological Sheet Map at 1:50,000, Geol. Surv. Japan, 134 pp., 1986 (in Japanese with Eng ...
... Kitamura, N. (Ed.), Cenozoic Arc Terrane of Northeast Honshu, Japan, 3 vols., Hobundo, Sendai, Japan, 1986 (in Japanese). Kitamura, N., T. Ishii, A. Sangawa, and H. Nakagawa, Geology of the Sendai district, with Geological Sheet Map at 1:50,000, Geol. Surv. Japan, 134 pp., 1986 (in Japanese with Eng ...
Seismic evidence of Alpine crustal thickening and wedging from the
... 3. Profile 6 is N-S oriented and 260 km long. It was recorded from two shots near the ends (H and K in Figure 1). The aim of this profile was to control the crustal structure in a N-S direction, perpendicular to the Alpine trends, from the Basque-Cantabrian Basin to the Iberian Chain. 4. Profile 7 i ...
... 3. Profile 6 is N-S oriented and 260 km long. It was recorded from two shots near the ends (H and K in Figure 1). The aim of this profile was to control the crustal structure in a N-S direction, perpendicular to the Alpine trends, from the Basque-Cantabrian Basin to the Iberian Chain. 4. Profile 7 i ...
The Quest for Self-Consistent Generation of Plate Tectonics in
... sub-oceanic mantle at the same depth (e.g., 100 km), for the same reasons. In summary, the models include highviscosity continental blocks embedded in an otherwise constant-viscosity domain. As such, they should be regarded as a logical step towards self-consistency from ‘rigid block’ models, in whi ...
... sub-oceanic mantle at the same depth (e.g., 100 km), for the same reasons. In summary, the models include highviscosity continental blocks embedded in an otherwise constant-viscosity domain. As such, they should be regarded as a logical step towards self-consistency from ‘rigid block’ models, in whi ...
A new concept of continental construction in the Central Asian
... tectonics (horizontal tectonics) and plume tectonics (vertical coremantle-crust geodynamics), e.g., birth/death of oceans, assembly/ breakup of supercontinents and their relation to bursts of superplumes, and correlated with recent geological processes recorded at oceancontinent convergent margins o ...
... tectonics (horizontal tectonics) and plume tectonics (vertical coremantle-crust geodynamics), e.g., birth/death of oceans, assembly/ breakup of supercontinents and their relation to bursts of superplumes, and correlated with recent geological processes recorded at oceancontinent convergent margins o ...
- Wiley Online Library
... Andean mountain building. The present-day crustal shortening in the Andes is clear from the GPS measurements, but the rate (30–40 mm/a) is higher than the geological shortening rate (<15 mm/a), suggesting that much of the present-day crustal shortening may recover during future earthquakes in the su ...
... Andean mountain building. The present-day crustal shortening in the Andes is clear from the GPS measurements, but the rate (30–40 mm/a) is higher than the geological shortening rate (<15 mm/a), suggesting that much of the present-day crustal shortening may recover during future earthquakes in the su ...
Variations in MidContinent Rift magma volumes consistent with
... of active source studies across Lake Superior [Cannon et al., 1989; Shay and Trehu, 1993] show that the crust was initially thinned to about one fourth of its original thickness. The resulting basin was filled with extrusive volcanics and sediments, and volcanic underplating, producing a rift pillow, ...
... of active source studies across Lake Superior [Cannon et al., 1989; Shay and Trehu, 1993] show that the crust was initially thinned to about one fourth of its original thickness. The resulting basin was filled with extrusive volcanics and sediments, and volcanic underplating, producing a rift pillow, ...
Presentation - School of Earth and Environment
... Unconformities and Faults: Problem 2 d) Structure contours of the fault can be drawn where the fault crosses the same topographical contour, like we can do with the beds. These show the fault dips to the South. Also, as we have already found out, the South of the fault is the downthrow side. This m ...
... Unconformities and Faults: Problem 2 d) Structure contours of the fault can be drawn where the fault crosses the same topographical contour, like we can do with the beds. These show the fault dips to the South. Also, as we have already found out, the South of the fault is the downthrow side. This m ...
Teaching Near Surface Geophysics in the Field
... Processing steps: Editing data (what % removed, why?), inversion parameters, number of iterations,… ...
... Processing steps: Editing data (what % removed, why?), inversion parameters, number of iterations,… ...
Tutorial: Velocity Estimation via Ray-based
... Guiziou, et al., 1990) or migrated depth information (Etgen, 1988; Stork, 1992; Kosloff et al., 1996; Bloor, 1998) or, more completely, we could use the measured amplitudes of the waveforms of the recorded data including the associated arrival times and phases (Worthington, 1984; Pratt et al., 1996) ...
... Guiziou, et al., 1990) or migrated depth information (Etgen, 1988; Stork, 1992; Kosloff et al., 1996; Bloor, 1998) or, more completely, we could use the measured amplitudes of the waveforms of the recorded data including the associated arrival times and phases (Worthington, 1984; Pratt et al., 1996) ...
Full waveform inversion of seismic waves reflected in a stratified
... our numerical results with an analytical solution derived by Philippacopoulos (1997, 1998) in the frequency–wavenumber domain for a homogeneous medium bounded by a free surface. The time domain solution is obtained via an inverse Hankel transform followed by a Fourier transform. This solution has al ...
... our numerical results with an analytical solution derived by Philippacopoulos (1997, 1998) in the frequency–wavenumber domain for a homogeneous medium bounded by a free surface. The time domain solution is obtained via an inverse Hankel transform followed by a Fourier transform. This solution has al ...
Seismic structure of the crust and uppermost mantle of the Capricorn
... The seismic structure of the Proterozoic Capricorn and Paterson Orogens and adjacent Archaean Yilgarn and Pilbara Cratons, Western Australia, is determined using a passive seismic approach. We use recordings of distant earthquakes made along two transects of 3-component broadband stations. The stati ...
... The seismic structure of the Proterozoic Capricorn and Paterson Orogens and adjacent Archaean Yilgarn and Pilbara Cratons, Western Australia, is determined using a passive seismic approach. We use recordings of distant earthquakes made along two transects of 3-component broadband stations. The stati ...
Earthscope
Earthscope is an earth science program using geological and geophysical techniques to explore the structure and evolution of the North American continent and to understand the processes controlling earthquakes and volcanoes. The project has three components: USARRAY, the Plate Boundary Observatory, and the San Andreas Fault Observatory at Depth.The project is funded by the National Science Foundation (NSF), and the data produced is publicly accessible in real-time. Organizations associated with the project include UNAVCO, the Incorporated Research Institutions for Seismology (IRIS), Stanford University, the United States Geological Survey (USGS) and National Aeronautics and Space Administration (NASA). Several international organizations also contribute to the initiative.