Geophysical-petrological model of the crust and upper mantle in the
... distribution of temperature, density, and mantle seismic velocities and the resulting surface heat flow, elevation, gravity, and geoid anomalies. LitMod-2D works under a forward modeling scheme; at each step, the model outputs (elevation, gravity and geoid anomalies, surface heat flow, and mantle seis ...
... distribution of temperature, density, and mantle seismic velocities and the resulting surface heat flow, elevation, gravity, and geoid anomalies. LitMod-2D works under a forward modeling scheme; at each step, the model outputs (elevation, gravity and geoid anomalies, surface heat flow, and mantle seis ...
Seismic characteristics and distribution of volcanic
... Abstract: A voluminous magmatic complex was emplaced in the Vøring and Møre basins during Paleocene/Eocene continental rifting and break-up in the NE Atlantic. This intrusive event has had a significant impact on deformation, source-rock maturation and fluid flow in the basins. Intrusive complexes a ...
... Abstract: A voluminous magmatic complex was emplaced in the Vøring and Møre basins during Paleocene/Eocene continental rifting and break-up in the NE Atlantic. This intrusive event has had a significant impact on deformation, source-rock maturation and fluid flow in the basins. Intrusive complexes a ...
Cascadia subducting plate fluids channelled to fore
... crust and uppermost mantle are dehydrated with downdip increasing temperature, and seismic tomography data indicate that these fluids have strongly serpentinized the overlying fore-arc mantle. Laboratory data show that such fore-arc mantle serpentinite has low permeability and likely blocks vertical ...
... crust and uppermost mantle are dehydrated with downdip increasing temperature, and seismic tomography data indicate that these fluids have strongly serpentinized the overlying fore-arc mantle. Laboratory data show that such fore-arc mantle serpentinite has low permeability and likely blocks vertical ...
Hawaii, Boundary Layers and Ambient
... over the years. What is new is that we now know the lateral heterogeneity in each region and this reinforces the importance of Gutenberg’s Region B, which includes the lid and the LVL, for mantle petrology. The negative shear velocity gradient in B implies a superadiabatic temperature gradient to de ...
... over the years. What is new is that we now know the lateral heterogeneity in each region and this reinforces the importance of Gutenberg’s Region B, which includes the lid and the LVL, for mantle petrology. The negative shear velocity gradient in B implies a superadiabatic temperature gradient to de ...
Large-Scale Thermo-chemical Structure of the Deep Mantle
... models (Ritsema et al. 2011) suggest that it may split into a western and an eastern province with a gap of several hundreds of kilometers in between. Both provinces have a trapezoidal shape, but the western region has stronger topography than the eastern region. Sharp boundaries at the southern ed ...
... models (Ritsema et al. 2011) suggest that it may split into a western and an eastern province with a gap of several hundreds of kilometers in between. Both provinces have a trapezoidal shape, but the western region has stronger topography than the eastern region. Sharp boundaries at the southern ed ...
Top driven asymmetric mantle convection
... proposed an ad hoc mantle geotherm that has become the canonical reference geotherm for subsequent petrological interpretations (see Anderson, 2012 and references therein). McKenzie and Bickle (1988) assumed that the mantle was homogeneous, fertile, vigorously convecting and adiabatic below 100 km d ...
... proposed an ad hoc mantle geotherm that has become the canonical reference geotherm for subsequent petrological interpretations (see Anderson, 2012 and references therein). McKenzie and Bickle (1988) assumed that the mantle was homogeneous, fertile, vigorously convecting and adiabatic below 100 km d ...
On the shallow origin of hotspots and the westward drift of the
... of the middle asthenosphere rather than the deep lower mantle as the source for intraplate Pacific hotspots has several implications. First, decoupling between the lithosphere and subasthenospheric mantle is greater than recorded by hotspot volcanic tracks (>100 mm/yr) due to undetectable shear in t ...
... of the middle asthenosphere rather than the deep lower mantle as the source for intraplate Pacific hotspots has several implications. First, decoupling between the lithosphere and subasthenospheric mantle is greater than recorded by hotspot volcanic tracks (>100 mm/yr) due to undetectable shear in t ...
Title Glossary of interest to earthquake and engineering
... from dynamic formation of a microcrack. Due to the small crack lengths, the frequencies of the radiated waves are in the kHz (acoustic or ultrasound) range. ...
... from dynamic formation of a microcrack. Due to the small crack lengths, the frequencies of the radiated waves are in the kHz (acoustic or ultrasound) range. ...
Upper-mantle S-velocity structure of central and western South
... data from the linear NARS array [Dost et al., 1984]. PWI was first applied to retrieve three-dimensional (3-D) upper mantle structure by Zielhuis and Nolet [1994]. Here, we apply PWI to image the 3-D S-velocity structure of the upper mantle of western and central South America using vertical compone ...
... data from the linear NARS array [Dost et al., 1984]. PWI was first applied to retrieve three-dimensional (3-D) upper mantle structure by Zielhuis and Nolet [1994]. Here, we apply PWI to image the 3-D S-velocity structure of the upper mantle of western and central South America using vertical compone ...
(PDF 8mb)
... Earthscope, in particular the USArray Transportable and Flexible Array components, has enabled the construction of high-resolution, three-dimensional models of the continental crust and mantle at scales ranging from continental (e.g., western US upper mantle) to regional (e.g., subducting oceanic cr ...
... Earthscope, in particular the USArray Transportable and Flexible Array components, has enabled the construction of high-resolution, three-dimensional models of the continental crust and mantle at scales ranging from continental (e.g., western US upper mantle) to regional (e.g., subducting oceanic cr ...
The fate of fluids released from subducting slab in
... study the fluid budget for an exceptionally young and hot subduction zone. We provide new quantitative information on the fate of that water rising into the forearc based on Pand S-wave velocities from 3-D seismic tomography. In this article we determine the distribution and concentrations of (a) se ...
... study the fluid budget for an exceptionally young and hot subduction zone. We provide new quantitative information on the fate of that water rising into the forearc based on Pand S-wave velocities from 3-D seismic tomography. In this article we determine the distribution and concentrations of (a) se ...
Mantle discontinuities beneath the Deccan volcanic
... velocity zone below 200 km were mapped through teleseismic P-wave tomography [14]. This seismic anomaly is seen to link to the Narmada rift and possibly extends further south beneath the Western Ghats, the main effusive phase in the DVP, where the tomograms were not well resolved. Earlier, tomograph ...
... velocity zone below 200 km were mapped through teleseismic P-wave tomography [14]. This seismic anomaly is seen to link to the Narmada rift and possibly extends further south beneath the Western Ghats, the main effusive phase in the DVP, where the tomograms were not well resolved. Earlier, tomograph ...
Continent-sized anomalous zones with low
... Edward J. Garnero*, Allen K. McNamara and Sang-Heon Shim Seismic images of Earth’s interior reveal two massive anomalous zones at the base of the mantle, above the core, where seismic waves travel slowly. The mantle materials that surround these anomalous regions are thought to be composed of cooler ...
... Edward J. Garnero*, Allen K. McNamara and Sang-Heon Shim Seismic images of Earth’s interior reveal two massive anomalous zones at the base of the mantle, above the core, where seismic waves travel slowly. The mantle materials that surround these anomalous regions are thought to be composed of cooler ...
Clutch tectonics and the partial attachment of lithospheric layers
... line (Fig. 6b). Although intense fabric develops in a narrow (m-scale) discontinuity, little fabric development will exist outside this zone as no displacement gradients exist. As such, the discontinuity forms a detachment zone because it removes mechanical communication between adjacent layers. It ...
... line (Fig. 6b). Although intense fabric develops in a narrow (m-scale) discontinuity, little fabric development will exist outside this zone as no displacement gradients exist. As such, the discontinuity forms a detachment zone because it removes mechanical communication between adjacent layers. It ...
Deep-mantle contributions to the surface dynamics of the North
... flow in the mantle is a model of the rheological structure of the mantle. Details of the viscous flow theory may be found elsewhere (Richards and Hager, 1984; Forte, 2007) and it suffices to point out that the flow calculations presented below are obtained on the basis of a gravitationally consistent, c ...
... flow in the mantle is a model of the rheological structure of the mantle. Details of the viscous flow theory may be found elsewhere (Richards and Hager, 1984; Forte, 2007) and it suffices to point out that the flow calculations presented below are obtained on the basis of a gravitationally consistent, c ...
Contents and Preface
... reasons, the crustal structure is much better known and is much better understood than the structure of the lithospheric mantle. While it is universally understood that the crust is highly heterogeneous, many geophysical models still treat the lithospheric mantle as an almost homogeneous layer. The ...
... reasons, the crustal structure is much better known and is much better understood than the structure of the lithospheric mantle. While it is universally understood that the crust is highly heterogeneous, many geophysical models still treat the lithospheric mantle as an almost homogeneous layer. The ...
Resolving the lithosphereasthenosphere boundary with seismic
... within the lithosphere and asthenosphere. It is still a matter of debate, however, how accurately and under what conditions surface waves can resolve the depth and thickness of the lithosphere–asthenosphere boundary (LAB). We investigate the sensitivity of Rayleigh waves to LAB properties and find t ...
... within the lithosphere and asthenosphere. It is still a matter of debate, however, how accurately and under what conditions surface waves can resolve the depth and thickness of the lithosphere–asthenosphere boundary (LAB). We investigate the sensitivity of Rayleigh waves to LAB properties and find t ...
G. Heinson, Electromagnetic studies of the lithosphere and
... defined in terms of their rheology. Lithosphere has high viscosity, and can be divided into an elastic region at temperatures below 350 ◦ C and an anelastic region above 650 ◦ C. Beneath the lithosphere lies the ductile asthenosphere, with one- to two-orders of magnitude lower viscosity. Asthenosphe ...
... defined in terms of their rheology. Lithosphere has high viscosity, and can be divided into an elastic region at temperatures below 350 ◦ C and an anelastic region above 650 ◦ C. Beneath the lithosphere lies the ductile asthenosphere, with one- to two-orders of magnitude lower viscosity. Asthenosphe ...
Imaging the lithosphere‐asthenosphere boundary
... teleseismic phase SS, which are sensitive to structure near the SS bouncepoint. Because these bouncepoints are about halfway between the sources and receivers, the observations provide a powerful tool for resolving structure in regions where seismic station coverage is sparse, such as the oceans. SS ...
... teleseismic phase SS, which are sensitive to structure near the SS bouncepoint. Because these bouncepoints are about halfway between the sources and receivers, the observations provide a powerful tool for resolving structure in regions where seismic station coverage is sparse, such as the oceans. SS ...
Mountain Building Processes in Four-Dimensions (4D-MB)
... break-off (Fox et al. 2015) and the isostatic compensation depth was instead situated at the lithosphereasthenosphere boundary (LAB) above the purported slab break (Fig. 2, section DD’). Thus, slab tearing rather than climate change may have triggered exhumation of the External Basement Massifs some ...
... break-off (Fox et al. 2015) and the isostatic compensation depth was instead situated at the lithosphereasthenosphere boundary (LAB) above the purported slab break (Fig. 2, section DD’). Thus, slab tearing rather than climate change may have triggered exhumation of the External Basement Massifs some ...
Dehydration of serpentinized slab mantle: Seismic evidence from southwest Japan
... The occurrence of intermediate-depth and deep earthquakes at 60–670 km depth range in the Wadati-Benioff zone is one of the enigmas of earth sciences because the lithostatic pressure at such depths appears to be too high for brittle fracture (see Kirby, 1995 for review). In some slabs, double seismi ...
... The occurrence of intermediate-depth and deep earthquakes at 60–670 km depth range in the Wadati-Benioff zone is one of the enigmas of earth sciences because the lithostatic pressure at such depths appears to be too high for brittle fracture (see Kirby, 1995 for review). In some slabs, double seismi ...
Lithospheric structure of the Rio Grande rift
... ago22. Even so, this suggests RGR formational strain rates of only 10216 to 10215 s21 (0.56 to 1 mm yr21). This low strain rate, along with increased temperature, may have enabled ductile deformation of the lithosphere, producing the observed symmetric region of laterally distributed pure-shear defo ...
... ago22. Even so, this suggests RGR formational strain rates of only 10216 to 10215 s21 (0.56 to 1 mm yr21). This low strain rate, along with increased temperature, may have enabled ductile deformation of the lithosphere, producing the observed symmetric region of laterally distributed pure-shear defo ...
The cold and relatively dry nature of mantle forearcs in subduction
... anisotropy effects are minor. Typical splitting times of 0.06–0.15 s are compatible with only 1–2% aggregate anisotropy or less25,26. If free fluids were present they would further reduce velocities and produce significantly greater velocity reduction per amount of H2O than creation of hydrous miner ...
... anisotropy effects are minor. Typical splitting times of 0.06–0.15 s are compatible with only 1–2% aggregate anisotropy or less25,26. If free fluids were present they would further reduce velocities and produce significantly greater velocity reduction per amount of H2O than creation of hydrous miner ...
Toward the reconciliation of seismological and petrological
... Shito et al., 2013; Chen et al., 2013; Kennett et al., 2014]. The details of the crustal model have only a mild influence on the nature of the Po and So after propagation for a few hundred kilometers, because the seismic energy spends little time in this zone. To represent the sheeted dyke complex of ...
... Shito et al., 2013; Chen et al., 2013; Kennett et al., 2014]. The details of the crustal model have only a mild influence on the nature of the Po and So after propagation for a few hundred kilometers, because the seismic energy spends little time in this zone. To represent the sheeted dyke complex of ...
Upper mantle beneath Southeast Asia from S velocity tomography
... inversions of multimode surface waves can produce useful resolution down to the TZ in a region as heterogeneous as the western Pacific. A puzzling low-velocity anomaly was detected beneath a long extinct spreading center, the Central Basin Ridge in the West Philippine Basin. Kato and Jordan [1999] c ...
... inversions of multimode surface waves can produce useful resolution down to the TZ in a region as heterogeneous as the western Pacific. A puzzling low-velocity anomaly was detected beneath a long extinct spreading center, the Central Basin Ridge in the West Philippine Basin. Kato and Jordan [1999] c ...