Geophysical Journal International
... asthenosphere boundary (LAB); and no heat flow across the lateral boundaries of the model. Beneath the LAB, the algorithm considers a 40-km-thick thermal buffer with a temperature of 1400 ◦ C at its base, in order to avoid unrealistic discontinuities between the conductive thermal gradient within th ...
... asthenosphere boundary (LAB); and no heat flow across the lateral boundaries of the model. Beneath the LAB, the algorithm considers a 40-km-thick thermal buffer with a temperature of 1400 ◦ C at its base, in order to avoid unrealistic discontinuities between the conductive thermal gradient within th ...
Local modification of the lithosphere beneath the central and
... key insights into this issue. Large-scale seismic tomography results show that high-velocity anomalies extend to deeper than 200 km beneath the central and western NCC, suggesting the presence of a thick cratonic mantle root in this region (e.g., Lebedev and Nolet, 2003; Huang and Zhao, 2006; Li and ...
... key insights into this issue. Large-scale seismic tomography results show that high-velocity anomalies extend to deeper than 200 km beneath the central and western NCC, suggesting the presence of a thick cratonic mantle root in this region (e.g., Lebedev and Nolet, 2003; Huang and Zhao, 2006; Li and ...
CRUSTAL STRUCTURE OF THE TIBETAN PLATEAU AND ITS
... Himalayas, the southern Tibet plateau, and Tien Shan. The results of receiver function studies show gentle northward dipping Moho beneath the Himalayas and increase of the dip of subduction near the Yarlung-Zangbo Suture, the boundary between the India plate and Tibet. This suggests that the Indian ...
... Himalayas, the southern Tibet plateau, and Tien Shan. The results of receiver function studies show gentle northward dipping Moho beneath the Himalayas and increase of the dip of subduction near the Yarlung-Zangbo Suture, the boundary between the India plate and Tibet. This suggests that the Indian ...
Crustal thinning of the northern continental margin of the South
... was rarely studied. The main objective of this study is to give a comprehensive understanding of the crustal features of the northern continental margin of the SCS. For that, we have conducted new seismic reflection profiles between Dongsha Island and Taiwan and combined these with several previous ...
... was rarely studied. The main objective of this study is to give a comprehensive understanding of the crustal features of the northern continental margin of the SCS. For that, we have conducted new seismic reflection profiles between Dongsha Island and Taiwan and combined these with several previous ...
Crustal Deformation
... How Geologists Use These Clues • We can mentally fill out the sketch to get an idea of the shape of the fold. • Note that we still have no idea how big the fold is, only what kind it is. 3. Small structures provide clues to much larger structures ...
... How Geologists Use These Clues • We can mentally fill out the sketch to get an idea of the shape of the fold. • Note that we still have no idea how big the fold is, only what kind it is. 3. Small structures provide clues to much larger structures ...
Plate Tectonics
... fi rst concept stated that regardless of how intricately the sedimentary rocks exposed in an outcrop are folded or tilted, when the sediments from which they formed were fi rst laid down they were originally laid down horizontally. Think about the sediments as they are deposited on the ocean botto ...
... fi rst concept stated that regardless of how intricately the sedimentary rocks exposed in an outcrop are folded or tilted, when the sediments from which they formed were fi rst laid down they were originally laid down horizontally. Think about the sediments as they are deposited on the ocean botto ...
2 April Notes
... Each of the 4 types of waves travels at a different velocity and can be calculated with different, complex equations. P‐Waves are the fastest, S‐Waves are the second fastest then the surface waves. ...
... Each of the 4 types of waves travels at a different velocity and can be calculated with different, complex equations. P‐Waves are the fastest, S‐Waves are the second fastest then the surface waves. ...
Printer-friendly Version - Solid Earth Discussions
... of 4–24 km. The P wave velocity in the uppermost mantle is 7.9–8.2 km s . The ratio of P wave velocity to S wave velocity varies typically from 1.67–1.70 in the upper crust to 1.77–1.80 in the lower crust. In the upper mantle the ratio is about 1.73 (e.g. Guggisberg, 1986; Grad and Luosto, 1987; Luo ...
... of 4–24 km. The P wave velocity in the uppermost mantle is 7.9–8.2 km s . The ratio of P wave velocity to S wave velocity varies typically from 1.67–1.70 in the upper crust to 1.77–1.80 in the lower crust. In the upper mantle the ratio is about 1.73 (e.g. Guggisberg, 1986; Grad and Luosto, 1987; Luo ...
Detecting low‐frequency earthquakes within non‐volcanic tremor in
... compared with the surrounding regions. Instead, the highest Vp/Vs ratio, and presumably the most elevated fluid pressures occur near the LV suture, which is partially creeping in the shallow crust [Lee et al., 2001] with numerous small earthquakes, occasionally large (M6‐7) earthquakes, and slow‐sli ...
... compared with the surrounding regions. Instead, the highest Vp/Vs ratio, and presumably the most elevated fluid pressures occur near the LV suture, which is partially creeping in the shallow crust [Lee et al., 2001] with numerous small earthquakes, occasionally large (M6‐7) earthquakes, and slow‐sli ...
How frequent are earthquakes?
... still be detected. Since the majority of seismograph stations are located on land this means that midocean events (usually on tectonic spreading centres) which might be thousands of kilometres from the nearest seismograph stations (and remember we need at least 3–4 stations to determine an event loc ...
... still be detected. Since the majority of seismograph stations are located on land this means that midocean events (usually on tectonic spreading centres) which might be thousands of kilometres from the nearest seismograph stations (and remember we need at least 3–4 stations to determine an event loc ...
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... their seismic waves travel all the way through Earth and can be recorded on the other side (Figure 12.2). This means that the seismic waves act like medical X rays used to take images of a person’s insides. There are about 100 to 200 earthquakes each year that are large enough (about Mw 7 6 ) to be ...
... their seismic waves travel all the way through Earth and can be recorded on the other side (Figure 12.2). This means that the seismic waves act like medical X rays used to take images of a person’s insides. There are about 100 to 200 earthquakes each year that are large enough (about Mw 7 6 ) to be ...
EarthComm_c2s6_185-197
... According to Wegener, there was a huge supercontinent called Pangea. (Pangea is Greek for “all land.”) About 200 million years ago, it broke into separate continents. The continents then moved apart. Wegener claimed that mountains were formed at the leading edge of the moving continent. He was also ...
... According to Wegener, there was a huge supercontinent called Pangea. (Pangea is Greek for “all land.”) About 200 million years ago, it broke into separate continents. The continents then moved apart. Wegener claimed that mountains were formed at the leading edge of the moving continent. He was also ...
The lithosphere under stress
... figure 1a for mature oceanic lithosphere. Using Parsons & McKenzie’s (1978) terminology, the mechanical boundary layer maintains a conductive thermal gradient and is mechanically isolated from the underlying well-stirred asthenosphere, while the thermal boundary layer of small-scale convection can b ...
... figure 1a for mature oceanic lithosphere. Using Parsons & McKenzie’s (1978) terminology, the mechanical boundary layer maintains a conductive thermal gradient and is mechanically isolated from the underlying well-stirred asthenosphere, while the thermal boundary layer of small-scale convection can b ...
The RAMESSES experiment—III. Controlled-source
... used previously to be replaced with the collection of continuous time series at 64 Hz sampling. All the LEMs and several of the ELFs were equipped with MT amplifiers for use in the MT experiment described by Heinson et al. (in preparation), as well as CSEM amplifiers. Instrument positions were deter ...
... used previously to be replaced with the collection of continuous time series at 64 Hz sampling. All the LEMs and several of the ELFs were equipped with MT amplifiers for use in the MT experiment described by Heinson et al. (in preparation), as well as CSEM amplifiers. Instrument positions were deter ...
Structural Geology Introduction/Review of Basic Principles
... Deformation - permanent change in the size and shape of rock by breaking or flow. (a) ...
... Deformation - permanent change in the size and shape of rock by breaking or flow. (a) ...
Imaging the lithosphere‐asthenosphere boundary
... [4] Here we use a new method to directly measure the thickness of the lithosphere over much of the Pacific plate at a resolution high enough to test hypotheses regarding the thickening of the lithosphere with respect to plate age and distance from the ridge, as well as the mechanism that defines the ...
... [4] Here we use a new method to directly measure the thickness of the lithosphere over much of the Pacific plate at a resolution high enough to test hypotheses regarding the thickening of the lithosphere with respect to plate age and distance from the ridge, as well as the mechanism that defines the ...
Active rifting and crustal thinning along the Rivera
... may be propagating towards the East Pacific Rise. Specifically: (1) A prominent decrease in the MBA values occurs in the area of the El Gordo graben, the maximum decrease being centered over the El Gordo volcanic complex, located in the center of the graben. This decrease is modeled as being the res ...
... may be propagating towards the East Pacific Rise. Specifically: (1) A prominent decrease in the MBA values occurs in the area of the El Gordo graben, the maximum decrease being centered over the El Gordo volcanic complex, located in the center of the graben. This decrease is modeled as being the res ...
Structural Design of Base-Isolation system for Tall Building in
... base isolation system, the combined use of the sliding bearings and the rubber bearings is developed, called Hybrid TASS system (Hybrid TAISEI shake suppression system). In this system, the yield shear force and the stiffness of the base isolation story can be easily designed by setting the ratio of ...
... base isolation system, the combined use of the sliding bearings and the rubber bearings is developed, called Hybrid TASS system (Hybrid TAISEI shake suppression system). In this system, the yield shear force and the stiffness of the base isolation story can be easily designed by setting the ratio of ...
Volcanic and seismic hazards at a proposed nuclear power site in
... kind. It was necessary, therefore, to acquire additional information directly related to the project. The objectives of this phase of the study were to: (1) characterize the tectonic setting and analyze the nature of Pliocene and Quaternary volcanism in the Indonesian Arc; (2) establish a seis- ...
... kind. It was necessary, therefore, to acquire additional information directly related to the project. The objectives of this phase of the study were to: (1) characterize the tectonic setting and analyze the nature of Pliocene and Quaternary volcanism in the Indonesian Arc; (2) establish a seis- ...
Three-dimensional density model of the upper mantle in
... need information for distant zones, therefore for the territory far exceeding the study area. The employed methods also require global distribution of all parameters (see below). Although the model of Schaeffer and Lebedev [2013] is global, it is characterized by high horizontal resolution compared ...
... need information for distant zones, therefore for the territory far exceeding the study area. The employed methods also require global distribution of all parameters (see below). Although the model of Schaeffer and Lebedev [2013] is global, it is characterized by high horizontal resolution compared ...
Science Highlights of the RCL Initiative
... Large-scale model for the Gulf of California region based on receiver functions and surface wave inversions. Triangles are the NARS-Baja stations and the green circles are locations of receiver functions. • Panels reveal pronounced low-velocity anomalies associated with major centers of seafloor spr ...
... Large-scale model for the Gulf of California region based on receiver functions and surface wave inversions. Triangles are the NARS-Baja stations and the green circles are locations of receiver functions. • Panels reveal pronounced low-velocity anomalies associated with major centers of seafloor spr ...
Microseismicity and focal mechanisms at the western termination of
... Continental deformation is commonly more complicated than plate tectonics predicts, for it is not limited to narrow boundaries between rigid lithospheric plates, but affects wide areas with horizontal dimensions much larger than the lithosphere thickness (England & Jackson 1989). The strength of con ...
... Continental deformation is commonly more complicated than plate tectonics predicts, for it is not limited to narrow boundaries between rigid lithospheric plates, but affects wide areas with horizontal dimensions much larger than the lithosphere thickness (England & Jackson 1989). The strength of con ...
Topography and geoid due to lithospheric mass anomalies
... all its imperfections, we think that our crustal data file gives a more reliable crustal thickness than that obtained using a simple ocean/continent distribution (Woodhouse & Dziewonski 1984). It is also based on more observations than a previous attempt by Nataf, Nakanishi & Anderson (1986) using o ...
... all its imperfections, we think that our crustal data file gives a more reliable crustal thickness than that obtained using a simple ocean/continent distribution (Woodhouse & Dziewonski 1984). It is also based on more observations than a previous attempt by Nataf, Nakanishi & Anderson (1986) using o ...
“Soft Story” and “Weak Story” in Earthquake Resistant Design: A
... building with modern architectural configuration. Also several articles and books were published with advices for architectural design in seismic zones (Guevara-Perez. 2009, pp. 64-73).Since then, authors such as Arnold and Reitherman, (1982) mentioned that size and geometric form were not enough p ...
... building with modern architectural configuration. Also several articles and books were published with advices for architectural design in seismic zones (Guevara-Perez. 2009, pp. 64-73).Since then, authors such as Arnold and Reitherman, (1982) mentioned that size and geometric form were not enough p ...
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.