Mantle flow, melting, and dehydration of the Iceland mantle plume
... flow and melting of a ridge-centered mantle plume using three-dimensional numerical models. Results indicate that the viscosity increase associated with dehydration prevents buoyancy forces from contributing significantly to plume upwelling above the dry solidus. Consequently, upwelling in the prima ...
... flow and melting of a ridge-centered mantle plume using three-dimensional numerical models. Results indicate that the viscosity increase associated with dehydration prevents buoyancy forces from contributing significantly to plume upwelling above the dry solidus. Consequently, upwelling in the prima ...
Lithospheric structure across the California Continental Borderland
... The Continental Borderland is arguably one of the most geologically unusual regions in the United States because of its history of deformation involving subduction, transtensional, and transpressional motion, as well as extension. The term Continental Borderland is applied to the region off the sout ...
... The Continental Borderland is arguably one of the most geologically unusual regions in the United States because of its history of deformation involving subduction, transtensional, and transpressional motion, as well as extension. The term Continental Borderland is applied to the region off the sout ...
Plate-kinematics and crustal dynamics of circum
... al., 1998). In the eastern portion of the plate-boundary zone, primary structures more closely reflect Caribbean–South America relative motion (east-west shear) because the two plates have no large, independent Andean terranes between them. Despite these complexities, this late Cenozoic tectonic set ...
... al., 1998). In the eastern portion of the plate-boundary zone, primary structures more closely reflect Caribbean–South America relative motion (east-west shear) because the two plates have no large, independent Andean terranes between them. Despite these complexities, this late Cenozoic tectonic set ...
- Wiley Online Library
... Inner Borderland and suggest the presence of a slab fragment beneath the Outer Borderland. ...
... Inner Borderland and suggest the presence of a slab fragment beneath the Outer Borderland. ...
A new model of lunar crust: asymmetry in crustal composition... Tomoko Arai , Hiroshi Takeda , Akira Yamaguchi
... model” and the “serial magmatism model”, assuming a thin surface magma ocean plus an underlying convective crystalline mush, called “magmasphere” (Warren, 1985). These models were once considered to have an advantage in the thermal aspect, since the Moon can be mostly differentiated by the magmasphe ...
... model” and the “serial magmatism model”, assuming a thin surface magma ocean plus an underlying convective crystalline mush, called “magmasphere” (Warren, 1985). These models were once considered to have an advantage in the thermal aspect, since the Moon can be mostly differentiated by the magmasphe ...
Isostasy, dynamic topography, and the elevation of the Apennines of
... inherently linked, one being the time derivative of the other, and as such they represent the components of mountain belt dynamics that are sensitive to lithospheric structure and rates of change, respectively. Elevation is often argued to be dominated by isostasy of the crust, which, in convergent ...
... inherently linked, one being the time derivative of the other, and as such they represent the components of mountain belt dynamics that are sensitive to lithospheric structure and rates of change, respectively. Elevation is often argued to be dominated by isostasy of the crust, which, in convergent ...
Deep-sea basins of the Atlantic ocean
... not only by its topography but also by its specific geological structure proved by deep-sea drilling. Six holes were drilled in its area: 3 in the south and 3 in the west and northwest. All of the southern holes were drilled in areas where the ocean floor was >4000 m deep, and the northern ones, at ...
... not only by its topography but also by its specific geological structure proved by deep-sea drilling. Six holes were drilled in its area: 3 in the south and 3 in the west and northwest. All of the southern holes were drilled in areas where the ocean floor was >4000 m deep, and the northern ones, at ...
Physiographic provinces of the Arctic Ocean seafloor
... provinces shown in Table 1 could not be characterized solely by bottom slope. In certain locations, the gradual nature of the changes in bottom inclination made it difficult to detect transitions between the continental rise and slope, as well as between the rise and abyssal plain; in these cases, s ...
... provinces shown in Table 1 could not be characterized solely by bottom slope. In certain locations, the gradual nature of the changes in bottom inclination made it difficult to detect transitions between the continental rise and slope, as well as between the rise and abyssal plain; in these cases, s ...
Earth`s first two billion years—The era of internally
... That the discriminants for modern rocks lack a valid statistical basis (Vermeesch, 2006), that they only poorly identify modern tectonic settings, and that they produce absurdities when applied to the Archean Earth are disregarded. Condie’s (2005b, p. 33) admonition that “geochemical data can be use ...
... That the discriminants for modern rocks lack a valid statistical basis (Vermeesch, 2006), that they only poorly identify modern tectonic settings, and that they produce absurdities when applied to the Archean Earth are disregarded. Condie’s (2005b, p. 33) admonition that “geochemical data can be use ...
Thermal evolution of the Earth as recorded by komatiites
... generation, and therefore provide important constraints on mantle conditions throughout Earth history. It is here that komatiites have played an important role, because their compositional characteristics have been used to trace mantle melting depths, temperatures and processes back into the Archean ...
... generation, and therefore provide important constraints on mantle conditions throughout Earth history. It is here that komatiites have played an important role, because their compositional characteristics have been used to trace mantle melting depths, temperatures and processes back into the Archean ...
Chapter 11 Notes
... Collisions between Continental and Oceanic Crust • Some mountains form when oceanic lithosphere and continental lithosphere collide at convergent plate boundaries. • In this type of collision, the oceanic lithosphere subducts beneath the continental lithosphere, producing large-scale deformation whi ...
... Collisions between Continental and Oceanic Crust • Some mountains form when oceanic lithosphere and continental lithosphere collide at convergent plate boundaries. • In this type of collision, the oceanic lithosphere subducts beneath the continental lithosphere, producing large-scale deformation whi ...
MANTLE- AND CRUST-DERIVED MAGMATISM IN THE
... In a subduction regime, the break-off and sinking of a lithospheric slab produces a widening gap above it, into which there is a convective in-flow of high temperature, low-density mantle material and associated rise of the isotherms that promote melting and cause post-collisional activity (Zeck et ...
... In a subduction regime, the break-off and sinking of a lithospheric slab produces a widening gap above it, into which there is a convective in-flow of high temperature, low-density mantle material and associated rise of the isotherms that promote melting and cause post-collisional activity (Zeck et ...
Early Paleozoic Tectonic and Thermomechanical
... UHP metamorphic rocks was a mixture of continental and mafic/ultramafic materials, derived either from oceanic mélanges or pieces of a rifted continental margin tectonically incorporated into an oceanic subduction channel. These observations require that the North Qaidam UHP metamorphic rocks origin ...
... UHP metamorphic rocks was a mixture of continental and mafic/ultramafic materials, derived either from oceanic mélanges or pieces of a rifted continental margin tectonically incorporated into an oceanic subduction channel. These observations require that the North Qaidam UHP metamorphic rocks origin ...
Hawaii, Boundary Layers and Ambient
... convection and plate tectonics can be regarded as two aspects of the same coupled system (Tackley, 1998) they can also be regarded as far-from-equilibrium self-organized thermodynamic systems that derive energy, material and information from each other (e.g. Anderson, 2007a). In the top-down or BL m ...
... convection and plate tectonics can be regarded as two aspects of the same coupled system (Tackley, 1998) they can also be regarded as far-from-equilibrium self-organized thermodynamic systems that derive energy, material and information from each other (e.g. Anderson, 2007a). In the top-down or BL m ...
11. GEODYNAMIC EVOLUTION OF THE CÔTE D`IVOIRE
... crusts. During Late Cretaceous times, the transform margin experienced continuous subsidence leading to the progressive upslope migration of the reef. An increasing subsidence rate characterized the early Coniacian, close to the time when the first continent/ocean transform transition occurred. No s ...
... crusts. During Late Cretaceous times, the transform margin experienced continuous subsidence leading to the progressive upslope migration of the reef. An increasing subsidence rate characterized the early Coniacian, close to the time when the first continent/ocean transform transition occurred. No s ...
The RAMESSES experiment—III. Controlled-source
... instruments to be obtained by applying the same least-squares fitting procedure as was used to extract data amplitudes. Although there is an implicit assumption that the noise level remained constant over the four days of the CSEM experiment, this approach allows direct comparison with the data. Noi ...
... instruments to be obtained by applying the same least-squares fitting procedure as was used to extract data amplitudes. Although there is an implicit assumption that the noise level remained constant over the four days of the CSEM experiment, this approach allows direct comparison with the data. Noi ...
Tracing the evolving flux from the subducting plate in the Tonga
... 1974; Gill, 1976), which has developed as a result of subduction of the Pacific lithosphere under the eastern edge of the Indian-Australian plate. Convergence between the two plates is ⬃5.3 cm/yr. in the Kermadec Arc (DeMets et al., 1990), peaking at ⬃20 cm/yr. in northern Tonga because of the addit ...
... 1974; Gill, 1976), which has developed as a result of subduction of the Pacific lithosphere under the eastern edge of the Indian-Australian plate. Convergence between the two plates is ⬃5.3 cm/yr. in the Kermadec Arc (DeMets et al., 1990), peaking at ⬃20 cm/yr. in northern Tonga because of the addit ...
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... lithosphere tends to preserve the various geochemical fractionation events that affected it, such as depletions due to melt extraction and enrichments due to subductionrelated metasomatism. Ancient subcontinental lithospheric mantle often has distinct isotopic compositions indicating isolation from ...
... lithosphere tends to preserve the various geochemical fractionation events that affected it, such as depletions due to melt extraction and enrichments due to subductionrelated metasomatism. Ancient subcontinental lithospheric mantle often has distinct isotopic compositions indicating isolation from ...
1 Apparent vertical Moho offsets under continental strike
... scatter in H- κ results and unclear reverberations in moveout curves due to lateral heterogeneity. The results are therefore typically smoothed laterally before interpretation (e.g. Zhu and Kanamori, 2000; Rumpfhuber et al., 2009; Eagar et al., 2011), so inferring a local Moho step may be questionab ...
... scatter in H- κ results and unclear reverberations in moveout curves due to lateral heterogeneity. The results are therefore typically smoothed laterally before interpretation (e.g. Zhu and Kanamori, 2000; Rumpfhuber et al., 2009; Eagar et al., 2011), so inferring a local Moho step may be questionab ...
Q and its Variation in the Earth`s Crust and Upper Mantle.
... earliest studies to the present. It is a rapidly growing field for which measurements have only recently become sufficiently plentiful and reliable to allow mapping at relatively small scales. It has long been known that measurement errors are large and it has recently become clear that systematic, ...
... earliest studies to the present. It is a rapidly growing field for which measurements have only recently become sufficiently plentiful and reliable to allow mapping at relatively small scales. It has long been known that measurement errors are large and it has recently become clear that systematic, ...
Analysis of the Global Data Set
... terrains such as Antarctica and the high-latitude oceans or large regions of Africa and South America. On a 5øgrid of the Earth's surface, those grid elements with at least one measurement comprise about 62% of the surface of the Earth (Figure 2), an increase of about 20% over the 1976 compilation. ...
... terrains such as Antarctica and the high-latitude oceans or large regions of Africa and South America. On a 5øgrid of the Earth's surface, those grid elements with at least one measurement comprise about 62% of the surface of the Earth (Figure 2), an increase of about 20% over the 1976 compilation. ...
Seismic detection and characterization of the
... Quaternary volcanism based on seismic tomography as well as other geophysical techniques. The difficulties of geophysical imaging of a crustal magma body are exemplified by the many studies conducted at Long Valley caldera, California (RUNDLE and HILL, 1988). Although a low-velocity zone beneath the ca ...
... Quaternary volcanism based on seismic tomography as well as other geophysical techniques. The difficulties of geophysical imaging of a crustal magma body are exemplified by the many studies conducted at Long Valley caldera, California (RUNDLE and HILL, 1988). Although a low-velocity zone beneath the ca ...
KoreaTaejonLetters
... occurring and if they are more likely to occur in certain locations. Hmm… my research says that there were most recent earthquakes in Japan, Florida, Indonesia, Thailand, India, California, etc, etc. It appears most frequently in the North/East part of the world. Especially in the continent of Asia. ...
... occurring and if they are more likely to occur in certain locations. Hmm… my research says that there were most recent earthquakes in Japan, Florida, Indonesia, Thailand, India, California, etc, etc. It appears most frequently in the North/East part of the world. Especially in the continent of Asia. ...
Plate tectonics
Plate tectonics (from the Late Latin tectonicus, from the Greek: τεκτονικός ""pertaining to building"") is a scientific theory that describes the large-scale motion of Earth's lithosphere. This theoretical model builds on the concept of continental drift which was developed during the first few decades of the 20th century. The geoscientific community accepted the theory after the concepts of seafloor spreading were later developed in the late 1950s and early 1960s.The lithosphere, which is the rigid outermost shell of a planet (on Earth, the crust and upper mantle), is broken up into tectonic plates. On Earth, there are seven or eight major plates (depending on how they are defined) and many minor plates. Where plates meet, their relative motion determines the type of boundary; convergent, divergent, or transform. Earthquakes, volcanic activity, mountain-building, and oceanic trench formation occur along these plate boundaries. The lateral relative movement of the plates typically varies from zero to 100 mm annually.Tectonic plates are composed of oceanic lithosphere and thicker continental lithosphere, each topped by its own kind of crust. Along convergent boundaries, subduction carries plates into the mantle; the material lost is roughly balanced by the formation of new (oceanic) crust along divergent margins by seafloor spreading. In this way, the total surface of the globe remains the same. This prediction of plate tectonics is also referred to as the conveyor belt principle. Earlier theories (that still have some supporters) propose gradual shrinking (contraction) or gradual expansion of the globe.Tectonic plates are able to move because the Earth's lithosphere has greater strength than the underlying asthenosphere. Lateral density variations in the mantle result in convection. Plate movement is thought to be driven by a combination of the motion of the seafloor away from the spreading ridge (due to variations in topography and density of the crust, which result in differences in gravitational forces) and drag, with downward suction, at the subduction zones. Another explanation lies in the different forces generated by the rotation of the globe and the tidal forces of the Sun and Moon. The relative importance of each of these factors and their relationship to each other is unclear, and still the subject of much debate.