Second Draft with Art and Photos September 2006
... bands radiating out form the hypocenter. These waves can be measured some time later by seismic stations, such as at locations 1 and 2. Seismic stations closer to the hypocenter, such as station 1, will detect it sooner than those farther away, like station 2. 2. The epicenter is the point on the su ...
... bands radiating out form the hypocenter. These waves can be measured some time later by seismic stations, such as at locations 1 and 2. Seismic stations closer to the hypocenter, such as station 1, will detect it sooner than those farther away, like station 2. 2. The epicenter is the point on the su ...
The heavy noble gas composition of the depleted MORB mantle
... The extent to which the noble gas composition of popping rock is representative of the depleted MORB mantle, however, is not clear. This is because the sample is highly enriched in trace elements (La/SmN ¼2.1; Dosso et al., 1991, 1993) compared to the normal depleted MORBs (N-MORBs; La/SmN r1) that ...
... The extent to which the noble gas composition of popping rock is representative of the depleted MORB mantle, however, is not clear. This is because the sample is highly enriched in trace elements (La/SmN ¼2.1; Dosso et al., 1991, 1993) compared to the normal depleted MORBs (N-MORBs; La/SmN r1) that ...
Seismic structure of Cocos and Malpelo Volcanic Ridges and
... uncertainty and robustness of the results are estimated by performing a Monte Carlo-type analysis. Our results show that the maximum crustal thickness along these profiles ranges from 16.5 km (southern Cocos) to 19 km (northern Cocos and Malpelo). Oceanic layer 2 thickness is quite uniform regardl ...
... uncertainty and robustness of the results are estimated by performing a Monte Carlo-type analysis. Our results show that the maximum crustal thickness along these profiles ranges from 16.5 km (southern Cocos) to 19 km (northern Cocos and Malpelo). Oceanic layer 2 thickness is quite uniform regardl ...
Burov, E., Lithosphere, mechanical properties, in
... lithosphere required for lifetime stability of geological structures, subduction or transmission of tectonic stresses, and forces over large spatial scales, including horizontal pressure gradients caused by lateral variations in lithospheric density structure and topography (gravity potential energy ...
... lithosphere required for lifetime stability of geological structures, subduction or transmission of tectonic stresses, and forces over large spatial scales, including horizontal pressure gradients caused by lateral variations in lithospheric density structure and topography (gravity potential energy ...
Tectonic Evolution and Dynamics of Deepwater Area of Pearl River
... cross-sections, most faults developed before 23 Ma and have large throws. Meanwhile, the stratigraphic development was not uniform. There are thick deposits in the sags but thin or even no deposits on the uplifts, which exhibits block faulting during the rifting stage. Few faults developed after 23 ...
... cross-sections, most faults developed before 23 Ma and have large throws. Meanwhile, the stratigraphic development was not uniform. There are thick deposits in the sags but thin or even no deposits on the uplifts, which exhibits block faulting during the rifting stage. Few faults developed after 23 ...
Constraints on mantle melting and composition and nature of slab
... oceanic plates are thought to play a key role in subduction zone (SZ) magmatism as they can transfer material from the subducting plate to the overlying mantle wedge, lowering the solidus of mantle peridotite and triggering partial melting [1–4]. Pressure-release melting at temperatures above dry pe ...
... oceanic plates are thought to play a key role in subduction zone (SZ) magmatism as they can transfer material from the subducting plate to the overlying mantle wedge, lowering the solidus of mantle peridotite and triggering partial melting [1–4]. Pressure-release melting at temperatures above dry pe ...
Mechanisms for the formation of ridge-axis topography at
... Lin et al. 1990). It contains six 20–80 km long active spreading segments that are offset by the Atlantis transform (69 km) and four non-transforms (<30 km) (Fig. 1a). While the off-axis morphology shows similar degrees of variation (e.g. Pariso, Sempere & Rommevaux 1995; Tucholke et al. 1997), we f ...
... Lin et al. 1990). It contains six 20–80 km long active spreading segments that are offset by the Atlantis transform (69 km) and four non-transforms (<30 km) (Fig. 1a). While the off-axis morphology shows similar degrees of variation (e.g. Pariso, Sempere & Rommevaux 1995; Tucholke et al. 1997), we f ...
Numerical models of slab migration in continental collision zones
... For the advancing case, the driving forces are debated. The advancing motion is often explained with far field stresses related to global plate motion that push the plates and force the slab to migrate towards the overriding plate. For example, to explain Indian indentation rates, the ridge push of ...
... For the advancing case, the driving forces are debated. The advancing motion is often explained with far field stresses related to global plate motion that push the plates and force the slab to migrate towards the overriding plate. For example, to explain Indian indentation rates, the ridge push of ...
Introduction to the special issue on “Subduction Zones”
... When an oceanic basin closes and continental lithosphere enters a subduction zone, the positive buoyancy of the continental crust will resist subduction, leading to a slow-down, and ultimately to the end of subduction (e.g., McKenzie, 1969). Continental collision is accompanied by severe crustal and ...
... When an oceanic basin closes and continental lithosphere enters a subduction zone, the positive buoyancy of the continental crust will resist subduction, leading to a slow-down, and ultimately to the end of subduction (e.g., McKenzie, 1969). Continental collision is accompanied by severe crustal and ...
Mechanisms of crustal growth in large igneous
... asthenospheric mantle) because of the contamination of the melts by various crustal lithologies as illustrated by the Scottish Tertiary volcanics (e.g., Dickin et al., 1987, among others). Another approach to discuss the origin of the igneous activity is to establish the pattern of magma flow within ...
... asthenospheric mantle) because of the contamination of the melts by various crustal lithologies as illustrated by the Scottish Tertiary volcanics (e.g., Dickin et al., 1987, among others). Another approach to discuss the origin of the igneous activity is to establish the pattern of magma flow within ...
Lithospheric deformation during the early stages of continental
... Rayleigh-Taylor-type instability of the mantle lithosphere as the former produces a distinct asymmetry in the crustal deformation which is observed in many small collisional orogens. Recent results from upper mantle scale numerical models of continental plate convergence demonstrate that it may not ...
... Rayleigh-Taylor-type instability of the mantle lithosphere as the former produces a distinct asymmetry in the crustal deformation which is observed in many small collisional orogens. Recent results from upper mantle scale numerical models of continental plate convergence demonstrate that it may not ...
Aseismic zone and earthquake segmentation associated with a
... oceanic plate, a veneer of thin sediments (200 ms) is present, which gradually thickens to 800 ms at the subduction front. The first 25 km of the frontal part of the accretionary prism consists of folded and faulted accreted sediments sloping gently seaward. The top of the oceanic crust is imaged al ...
... oceanic plate, a veneer of thin sediments (200 ms) is present, which gradually thickens to 800 ms at the subduction front. The first 25 km of the frontal part of the accretionary prism consists of folded and faulted accreted sediments sloping gently seaward. The top of the oceanic crust is imaged al ...
Chapter 17. The Other Isotopes
... the garnet (gt) and clinopyroxene (cpx) structures. In other words, some of the so-called LIL elements are actually compatible in gt and cpx. The crust is also not excessively enriched in lithium, sodium, lead, bismuth and helium. ...
... the garnet (gt) and clinopyroxene (cpx) structures. In other words, some of the so-called LIL elements are actually compatible in gt and cpx. The crust is also not excessively enriched in lithium, sodium, lead, bismuth and helium. ...
Geochemistry, Geophysics, Geosystems
... that the largest differences between the end-member models in terms of the estimated strength and Te distributions are for the areas characterized by an ‘‘intermediate’’ thermal regime. Therefore, in these regions uncertainties in factors other than temperature estimates play a significant role in de ...
... that the largest differences between the end-member models in terms of the estimated strength and Te distributions are for the areas characterized by an ‘‘intermediate’’ thermal regime. Therefore, in these regions uncertainties in factors other than temperature estimates play a significant role in de ...
Geophysical Journal International
... values beneath the Sanandaj Sirjan zone (SSZ; 55–63 km), in agreement with seismic data. Major discrepancies in Moho depth from those derived from seismic data are locally found in the SSZ (central Zagros) and Alborz Mountains where more moderate crustal thicknesses are modelled. Results on the lith ...
... values beneath the Sanandaj Sirjan zone (SSZ; 55–63 km), in agreement with seismic data. Major discrepancies in Moho depth from those derived from seismic data are locally found in the SSZ (central Zagros) and Alborz Mountains where more moderate crustal thicknesses are modelled. Results on the lith ...
Chapter 14. Magmas: Windows into the Mantle
... enter or leave the mantle, one can obtain cosmic ratios of the refractory elements except for Mg/Si and other elements likely to enter dense refractory residues of mantle differentiation . Likewise. this mix is deficient in the siderophile elements, which are plausibly in the core, and the volatile ...
... enter or leave the mantle, one can obtain cosmic ratios of the refractory elements except for Mg/Si and other elements likely to enter dense refractory residues of mantle differentiation . Likewise. this mix is deficient in the siderophile elements, which are plausibly in the core, and the volatile ...
Numerical models of subduction and forearc deformation
... that known deformations between major earthquakes are best explained by a vertical force acting downward on the base of the lithosphere in the vicinity of the trench. Such a force could be caused by pull of the dense subducted lithosphere. Stresses resulting from this force system are illustrated in ...
... that known deformations between major earthquakes are best explained by a vertical force acting downward on the base of the lithosphere in the vicinity of the trench. Such a force could be caused by pull of the dense subducted lithosphere. Stresses resulting from this force system are illustrated in ...
Plate Tectonics - The Web site cannot be found
... new oceanic lithosphere (especially along and in the vicinity of the MORs, but also when this new lithosphere cools) follows a process analogous to the transition of water to ice, and is accompanied by large release of energy (Fig. 3.2). Much of the heat from the Earth’s interior is output to the at ...
... new oceanic lithosphere (especially along and in the vicinity of the MORs, but also when this new lithosphere cools) follows a process analogous to the transition of water to ice, and is accompanied by large release of energy (Fig. 3.2). Much of the heat from the Earth’s interior is output to the at ...
Geochemical investigation of serpentinized oceanic lithospheric
... The petrology and geochemistry of serpentinized harzburgites within the Feather River Ophiolite in northern California were investigated to constrain the origin of serpentinization. Trace-element systematics indicate that serpentinization was associated almost solely with relatively low temperature ...
... The petrology and geochemistry of serpentinized harzburgites within the Feather River Ophiolite in northern California were investigated to constrain the origin of serpentinization. Trace-element systematics indicate that serpentinization was associated almost solely with relatively low temperature ...
Deep structures and breakup along volcanic rifted margins: insights
... Three-dimensional multichannel seismic survey and well data allows a deeper insight into rifting mechanisms and crustal structure of the Norwegian volcanic rifted margin. A surprising high-velocity lower crustal dome marked by a strong amplitude reflection (T Reflection) is described below the north ...
... Three-dimensional multichannel seismic survey and well data allows a deeper insight into rifting mechanisms and crustal structure of the Norwegian volcanic rifted margin. A surprising high-velocity lower crustal dome marked by a strong amplitude reflection (T Reflection) is described below the north ...
Zuni–Bandera volcanism, Rio Grande, USA — Melt formation in
... The Zuni–Bandera Volcanic Field (ZBVF) is a late-Neogene volcanic field on the boundary of the stable Colorado Plateau and the active Rio Grande Rift. Alkalic and tholeiitic magmas have erupted through Proterozoic continental crust with the tholeiitic magmas having undergone shallow-level fractional ...
... The Zuni–Bandera Volcanic Field (ZBVF) is a late-Neogene volcanic field on the boundary of the stable Colorado Plateau and the active Rio Grande Rift. Alkalic and tholeiitic magmas have erupted through Proterozoic continental crust with the tholeiitic magmas having undergone shallow-level fractional ...
Hot Spots and Mantle Plumes - Assets
... Hot spots are anomalous areas of surface volcanism that cannot be directly associated with plate tectonic processes. The term hot spot is used rather loosely. It is often applied to any long-lived volcanic center that is not part of the global network of mid-ocean ridges and island arcs. The classic ...
... Hot spots are anomalous areas of surface volcanism that cannot be directly associated with plate tectonic processes. The term hot spot is used rather loosely. It is often applied to any long-lived volcanic center that is not part of the global network of mid-ocean ridges and island arcs. The classic ...
Origin of the concentrated deformation zone in the Japanese Islands... accumulation process of intraplate earthquakes
... that stable frictional sliding occurs in the upper crust. On the other hand, what is measured by GPS arrays is a present day deformation and it is influenced by the occurrence of individual earthquakes (Sagiya, 2004). The observed difference in deformation rate between in and around the NKTZ is almo ...
... that stable frictional sliding occurs in the upper crust. On the other hand, what is measured by GPS arrays is a present day deformation and it is influenced by the occurrence of individual earthquakes (Sagiya, 2004). The observed difference in deformation rate between in and around the NKTZ is almo ...
Shear zones in the Proterozoic lithosphere of the
... The tectonic history of the Arabian–Nubian shield is complicated by conflicting evidence. Global surface wave tomography models consistently place a low-velocity anomaly under the Red Sea rift (e.g. Zhang and Tanimoto, 1993), suggesting that an upwelling plume currently erodes the Arabian lithospher ...
... The tectonic history of the Arabian–Nubian shield is complicated by conflicting evidence. Global surface wave tomography models consistently place a low-velocity anomaly under the Red Sea rift (e.g. Zhang and Tanimoto, 1993), suggesting that an upwelling plume currently erodes the Arabian lithospher ...
Post-glacial rebound
Post-glacial rebound (sometimes called continental rebound) is the rise of land masses that were depressed by the huge weight of ice sheets during the last glacial period, through a process known as isostatic depression. Post-glacial rebound and isostatic depression are different parts of a process known as either glacial isostasy, glacial isostatic adjustment, or glacioisostasy. Glacioisostasy is the solid Earth deformation associated with changes in ice mass distribution. The most obvious and direct affects of post-glacial rebound are readily apparent in northern Europe (especially Scotland, Estonia, Latvia, Fennoscandia, and northern Denmark), Siberia, Canada, the Great Lakes of Canada and the United States, the coastal region of the US state of Maine, parts of Patagonia, and Antarctica. However, through processes known as ocean siphoning and continental levering, the effects of post-glacial rebound on sea-level are felt globally far from the locations of current and former ice sheets.