The Lithosphere-Asthenosphere Boundary
... depends on the form of the volatiles—water in nominally anhydrous minerals such as olivine versus serpentine, for example—but the former case would typically be expected at asthenospheric temperatures. Direct experimental constraints on the effects of water in olivine at seismic frequencies are at a ...
... depends on the form of the volatiles—water in nominally anhydrous minerals such as olivine versus serpentine, for example—but the former case would typically be expected at asthenospheric temperatures. Direct experimental constraints on the effects of water in olivine at seismic frequencies are at a ...
Morphotectonic features on Titan and their possible origin
... summarized in Table 1. Table 1 shows that silicate materials, when compared to water ice, exhibit higher viscosity, Young modulus i.e. the ratio of linear stress to linear strain and melting temperature, but display lower density. As a result, the homologous temperature, on which rheology depends, i ...
... summarized in Table 1. Table 1 shows that silicate materials, when compared to water ice, exhibit higher viscosity, Young modulus i.e. the ratio of linear stress to linear strain and melting temperature, but display lower density. As a result, the homologous temperature, on which rheology depends, i ...
Furnace of Creation, Cradle of Destruction: A Journey to the
... one Japanese myth has a massive spider dwelling within the earth and causing volcanoes to erupt. Volcanoes have always played a central role in the mythology of Japan—a land with more than a hundred active volcanoes. The most famous of all the Japanese volcanoes is the sacred Mount Fuji (Fujiyama—th ...
... one Japanese myth has a massive spider dwelling within the earth and causing volcanoes to erupt. Volcanoes have always played a central role in the mythology of Japan—a land with more than a hundred active volcanoes. The most famous of all the Japanese volcanoes is the sacred Mount Fuji (Fujiyama—th ...
Major and Trace Element Composition of the Depleted MORB
... In place of assuming a set of bulk partition coefficients or a degree of melt extraction – and instead, solving for these parameters – we use in this paper the following constraints in deriving an average trace element composition of DMM: 1) trace element content of clinopyroxenes from abyssal perid ...
... In place of assuming a set of bulk partition coefficients or a degree of melt extraction – and instead, solving for these parameters – we use in this paper the following constraints in deriving an average trace element composition of DMM: 1) trace element content of clinopyroxenes from abyssal perid ...
The strength of faults in the crust in the western
... thus anelastic everywhere, and the active deformation mechanisms are either frictional sliding along faults or nonlinear dislocation creep. In dislocation creep, ε̄ (strain-rate) relates to stress (σ) and creep activation energy (Q) through the power law equation ε̄ ∝ Aσn exp (−Q/RT), where A is the ...
... thus anelastic everywhere, and the active deformation mechanisms are either frictional sliding along faults or nonlinear dislocation creep. In dislocation creep, ε̄ (strain-rate) relates to stress (σ) and creep activation energy (Q) through the power law equation ε̄ ∝ Aσn exp (−Q/RT), where A is the ...
Durham Research Online
... Magni et al., 2012], and horizontal compressive stresses are expected, resulting in significant shortening. This may explain the tendency of the continental plate to indent into the overriding plate as observed for the Arabia and India. On the other hand, in the delamination scenario, the slab, which ...
... Magni et al., 2012], and horizontal compressive stresses are expected, resulting in significant shortening. This may explain the tendency of the continental plate to indent into the overriding plate as observed for the Arabia and India. On the other hand, in the delamination scenario, the slab, which ...
Where and why do large shallow intraslab earthquakes occur?
... are used. We judge whether they occurred within a slab or not mainly based on their focal mechanisms, making references to relative plate motions and focal mechanisms of nearby smaller events, and depths. We use depths from individual studies if available; if not, we use Harvard centroid depths that ...
... are used. We judge whether they occurred within a slab or not mainly based on their focal mechanisms, making references to relative plate motions and focal mechanisms of nearby smaller events, and depths. We use depths from individual studies if available; if not, we use Harvard centroid depths that ...
Earth,Tests,Ch12
... B) P waves are faster in the inner core than in the outer core C) S waves are slower in the inner core than in the outer core D) S waves are focused at the center of the P-wave shadow zone Answer: B Diff: 1 ...
... B) P waves are faster in the inner core than in the outer core C) S waves are slower in the inner core than in the outer core D) S waves are focused at the center of the P-wave shadow zone Answer: B Diff: 1 ...
Simulating the thermochemical magmatic and tectonic evolution of
... convection models to Venus. For isoviscous 3-D spherical models Schubert et al. [1990] found that a rigid outer boundary condition produces more numerous plumes and less coherent downwellings than a free-slip outer boundary condition. Increasing the viscosity contrast to produce sluggish-lid or stag ...
... convection models to Venus. For isoviscous 3-D spherical models Schubert et al. [1990] found that a rigid outer boundary condition produces more numerous plumes and less coherent downwellings than a free-slip outer boundary condition. Increasing the viscosity contrast to produce sluggish-lid or stag ...
Seismology - Università degli studi di Trieste
... Given the arrival times and amplitudes of several seismic phases on a number of stations, compute distribution of velocity, density and attenuation coefficient with depth, and positions of all discontinuities. This is very difficult and often does not give a unique solution. Instead, a range of solu ...
... Given the arrival times and amplitudes of several seismic phases on a number of stations, compute distribution of velocity, density and attenuation coefficient with depth, and positions of all discontinuities. This is very difficult and often does not give a unique solution. Instead, a range of solu ...
Lithospheric and upper mantle structure of the northeastern Tibetan
... northern margin of the Kunlun Mountains, a 10 km Moho offset across the Jinsha River Suture and gently northward dipping Moho beneath the Qaidam Basin. A region in the central Qiangtang Terrane with higher than normal crustal Vp/Vs ratio of 1.83 can be the result of the Eocene magmatic event. In th ...
... northern margin of the Kunlun Mountains, a 10 km Moho offset across the Jinsha River Suture and gently northward dipping Moho beneath the Qaidam Basin. A region in the central Qiangtang Terrane with higher than normal crustal Vp/Vs ratio of 1.83 can be the result of the Eocene magmatic event. In th ...
Chapter 1- INTRODUCTION 1.1. Mantle Rocks This study is
... transformations as upper mantle olivine changes first into spinel and then into perovskite structured high-pressure polymorphs. Finally, the crust is a compositionally distinct layer overlying the mantle that concentrates preferentially the incompatible elements derived by partial melting of the man ...
... transformations as upper mantle olivine changes first into spinel and then into perovskite structured high-pressure polymorphs. Finally, the crust is a compositionally distinct layer overlying the mantle that concentrates preferentially the incompatible elements derived by partial melting of the man ...
Indentation of a continent with a built
... sand layer led to internal buoyancy forces that were stabilized by gravity driving isostatic adjustment. Following Ramberg (1968) and Artyushkov (1974), isostatic adjustment could be distinguished into three stages ( Fig. 3 I–III ). The first stage ( loading) resulted in isostatic imbalance and grav ...
... sand layer led to internal buoyancy forces that were stabilized by gravity driving isostatic adjustment. Following Ramberg (1968) and Artyushkov (1974), isostatic adjustment could be distinguished into three stages ( Fig. 3 I–III ). The first stage ( loading) resulted in isostatic imbalance and grav ...
Generation of plate tectonics from mantle convection
... core premise of the working mathematical model of plate tectonics as originally prescribed by Morgan (1968) and McKenzie and Parker (1967) and continues to be used in present-day plate motion models (e.g., Argus and Gordon, 1991); (see Chapter 6.08). Plate-tectonic theory divides such surface motion ...
... core premise of the working mathematical model of plate tectonics as originally prescribed by Morgan (1968) and McKenzie and Parker (1967) and continues to be used in present-day plate motion models (e.g., Argus and Gordon, 1991); (see Chapter 6.08). Plate-tectonic theory divides such surface motion ...
Lithium Isotope Variations in Ocean Island
... generally appears to be controlled by processes such as magma generation and crust formation, mantle convection and material recycling, as well as metasomatism, the relative contribution of these processes to the heterogeneity of the mantle is still debated. Combined studies of ocean island basalts ...
... generally appears to be controlled by processes such as magma generation and crust formation, mantle convection and material recycling, as well as metasomatism, the relative contribution of these processes to the heterogeneity of the mantle is still debated. Combined studies of ocean island basalts ...
Crustal Structure at the Continental Margin South of South Africa
... In a number of areas, the geological basement crops out extensively on the sea floor; these areas are shown in Fig. 2. Those areas holding the greatest implications for the gravity interpretation are the Agulhas Arch antiform of Palaeozoic and Precambrian rocks (Gentle 1970), the Agulhas marginal fr ...
... In a number of areas, the geological basement crops out extensively on the sea floor; these areas are shown in Fig. 2. Those areas holding the greatest implications for the gravity interpretation are the Agulhas Arch antiform of Palaeozoic and Precambrian rocks (Gentle 1970), the Agulhas marginal fr ...
The continent marginal crust characteristic of nothern South China
... and Fig.9a). It has better control in strata sequences because of well log data drilled by ODP (point out the positions in Fig.1; site 1146 and site 1148). We see seismic basement separate by normal faults and form grabens filled by sediment between them. We can’t find any intruded or extruded igneo ...
... and Fig.9a). It has better control in strata sequences because of well log data drilled by ODP (point out the positions in Fig.1; site 1146 and site 1148). We see seismic basement separate by normal faults and form grabens filled by sediment between them. We can’t find any intruded or extruded igneo ...
Subduction-related intermediate-depth and deep seismicity in Italy
... the Northern Apennines assumes a 70 km thick continental slab dipping 60◦ . We consider heat production for a 20 km thick continental crust. The assumption of 20 km of subducting continental lithosphere is compatible with the thin-skinned tectonics (see the previous section) which characterises the ...
... the Northern Apennines assumes a 70 km thick continental slab dipping 60◦ . We consider heat production for a 20 km thick continental crust. The assumption of 20 km of subducting continental lithosphere is compatible with the thin-skinned tectonics (see the previous section) which characterises the ...
The mantle plume debate in undergraduate
... The plumes that Morgan envisioned were essentially vertical features, fixed with respect to one another. This original mantle plume theory has been appended and modified in a number of ways. Many modifications have been criticized as being ad hoc (e.g., Anderson, 2000); the fact that the theory is s ...
... The plumes that Morgan envisioned were essentially vertical features, fixed with respect to one another. This original mantle plume theory has been appended and modified in a number of ways. Many modifications have been criticized as being ad hoc (e.g., Anderson, 2000); the fact that the theory is s ...
Rheology and strength of the lithosphere - Evgueni Burov
... reasoning refers to the fact that seismicity is characteristic of shorttime scale behavior, which is physically unrelated to long-term rheology because at this short time scale visco-elasto-plastic lithosphere is expected to deform only in brittleeelastic mode. Consequently, there may be no direct c ...
... reasoning refers to the fact that seismicity is characteristic of shorttime scale behavior, which is physically unrelated to long-term rheology because at this short time scale visco-elasto-plastic lithosphere is expected to deform only in brittleeelastic mode. Consequently, there may be no direct c ...
FREE Sample Here
... class are designated as specific plates and plate margins that move with a set of tape measures. The setting is the western margin of North America 40 Ma, involving the Pacific, Farallon, and North American plates, a spreading ridge, and a subduction zone. Five students are designated as follows: St ...
... class are designated as specific plates and plate margins that move with a set of tape measures. The setting is the western margin of North America 40 Ma, involving the Pacific, Farallon, and North American plates, a spreading ridge, and a subduction zone. Five students are designated as follows: St ...
The Dynamic Earth - Betavak-NLT
... on an important consequence of the dynamic Earth: earthquakes. The first three chapters combine to form the basis of this course. You will have completed the course only when you have finished these chapters and one of the optional chapters (Chapter 4, 5 or 6). The other optional chapters can be use ...
... on an important consequence of the dynamic Earth: earthquakes. The first three chapters combine to form the basis of this course. You will have completed the course only when you have finished these chapters and one of the optional chapters (Chapter 4, 5 or 6). The other optional chapters can be use ...
Wrench faults down to the asthenosphere
... shear zones developed under lower temperature conditions (cm to hundred m). This points out that, at these high temperatures, strain localization was less efficient and strain was distributed over a larger volume of rocks than it is usually observed in upper crustal shear zones. Rocks within the she ...
... shear zones developed under lower temperature conditions (cm to hundred m). This points out that, at these high temperatures, strain localization was less efficient and strain was distributed over a larger volume of rocks than it is usually observed in upper crustal shear zones. Rocks within the she ...
Scandinavia`s North Atlantic passive margin
... and basin domain but also large portions of the onshore domains of the Scandinavian Caledonides. Combined information from structural geology, potential field data, regional geology, basin development, and geomorphology made it possible to propose a new definition of the passive margin. The rift sho ...
... and basin domain but also large portions of the onshore domains of the Scandinavian Caledonides. Combined information from structural geology, potential field data, regional geology, basin development, and geomorphology made it possible to propose a new definition of the passive margin. The rift sho ...
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 ...
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.