Geodynamic models of Cordilleran orogens
... The central Andes represents the type example of a Cordilleran orogen, in which crustal shortening has produced a continental mountain belt above an active subduction zone. Geological studies indicate that the central Andes was primarily built through 200 to >500 km of shortening of the western Sout ...
... The central Andes represents the type example of a Cordilleran orogen, in which crustal shortening has produced a continental mountain belt above an active subduction zone. Geological studies indicate that the central Andes was primarily built through 200 to >500 km of shortening of the western Sout ...
Ridge subduction and porphyry copper
... million tones. Plate reconstruction shows that eastern China became an active continental margin from the Jurassic [9, 10]. Similar to the South and North Americas, there are also abundant adakite and/or adakitic rocks in eastern China, many of which show Cu-Au mineralization, but large deposits wit ...
... million tones. Plate reconstruction shows that eastern China became an active continental margin from the Jurassic [9, 10]. Similar to the South and North Americas, there are also abundant adakite and/or adakitic rocks in eastern China, many of which show Cu-Au mineralization, but large deposits wit ...
Behaviour of high field strength elements in subduction zones
... the Earth’s mantle, old subducted oceanic crust typically dehydrates. In contrast to older models, arguing that old oceanic crust tends not to reach the solidus (e.g., [3]) more recent models [4] suggest that oceanic crust as old as 80 My can reach the solidus. There is general consensus that meltin ...
... the Earth’s mantle, old subducted oceanic crust typically dehydrates. In contrast to older models, arguing that old oceanic crust tends not to reach the solidus (e.g., [3]) more recent models [4] suggest that oceanic crust as old as 80 My can reach the solidus. There is general consensus that meltin ...
Three-dimensional crustal structure of the Mariana island arc from
... varies between 2.4 cm a1 to the WNW at 12°N and 6.1 cm a1 to the NW at 34°N [Seno et al., 1993]. A welldeveloped back-arc spreading center exists west of the Mariana segment of the subduction zone and estimates of the full spreading rate vary between 3.0 cm a1 and 4.3 cm a1 [Bibee et al., 1980; ...
... varies between 2.4 cm a1 to the WNW at 12°N and 6.1 cm a1 to the NW at 34°N [Seno et al., 1993]. A welldeveloped back-arc spreading center exists west of the Mariana segment of the subduction zone and estimates of the full spreading rate vary between 3.0 cm a1 and 4.3 cm a1 [Bibee et al., 1980; ...
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... zone, implying that Kohistan and India moved northwards on the same plate, although separated, during much of Cretaceous time. Collision of Kohistan with the Karakorum caused a new, north-dipping subduction zone to form on the south side of Kohistan, leading to collision with India in early Tertiary ...
... zone, implying that Kohistan and India moved northwards on the same plate, although separated, during much of Cretaceous time. Collision of Kohistan with the Karakorum caused a new, north-dipping subduction zone to form on the south side of Kohistan, leading to collision with India in early Tertiary ...
Bebout Metamorphic chemical geodynamics of subduction zones
... Nb/U, Rb/Cs), that is, ratios for which values for mantlederived lavas (arc lavas, ocean island basalts) reflect the values of their source regions rather than reflecting later ...
... Nb/U, Rb/Cs), that is, ratios for which values for mantlederived lavas (arc lavas, ocean island basalts) reflect the values of their source regions rather than reflecting later ...
Metamorphic chemical geodynamics of subduction zones
... Nb/U, Rb/Cs), that is, ratios for which values for mantlederived lavas (arc lavas, ocean island basalts) reflect the values of their source regions rather than reflecting later ...
... Nb/U, Rb/Cs), that is, ratios for which values for mantlederived lavas (arc lavas, ocean island basalts) reflect the values of their source regions rather than reflecting later ...
Evolution of the Earth as an andesite planet: water
... 40 vs. 6 km, respectively. The contrast in density is due to a difference in their average compositions; the continental crust is intermediate or andesitic, containing ~60 wt% SiO2, whereas the oceanic crust is mafic or basaltic, containing ~50 wt% SiO2 (e.g., Christensen and Mooney 1995; Kelemen 19 ...
... 40 vs. 6 km, respectively. The contrast in density is due to a difference in their average compositions; the continental crust is intermediate or andesitic, containing ~60 wt% SiO2, whereas the oceanic crust is mafic or basaltic, containing ~50 wt% SiO2 (e.g., Christensen and Mooney 1995; Kelemen 19 ...
Evolution of the Earth as an andesite planet: water, plate tectonics
... 40 vs. 6 km, respectively. The contrast in density is due to a difference in their average compositions; the continental crust is intermediate or andesitic, containing ~60 wt% SiO2, whereas the oceanic crust is mafic or basaltic, containing ~50 wt% SiO2 (e.g., Christensen and Mooney 1995; Kelemen 19 ...
... 40 vs. 6 km, respectively. The contrast in density is due to a difference in their average compositions; the continental crust is intermediate or andesitic, containing ~60 wt% SiO2, whereas the oceanic crust is mafic or basaltic, containing ~50 wt% SiO2 (e.g., Christensen and Mooney 1995; Kelemen 19 ...
Spatial and temporal variability of suspended sediment
... (g) Creation of multiple regression equations for SSSY assessment in ungauged river basins. This approach was implemented for both permanent and ephemeral rivers in the Kamchatka Krai, which includes the Kamchatka Peninsula, rivers flowing into Penzhina Bay (from Cape Taigonos in the west, to Rekkin ...
... (g) Creation of multiple regression equations for SSSY assessment in ungauged river basins. This approach was implemented for both permanent and ephemeral rivers in the Kamchatka Krai, which includes the Kamchatka Peninsula, rivers flowing into Penzhina Bay (from Cape Taigonos in the west, to Rekkin ...
LOW RES
... and thermal coupling. Mechanical coupling (viscous traction) between the subducting slab and the base of the mantle wedge drives corner flow [McKenzie, 1969], a type of forced convection. The subducting slab also cools the base of the mantle wedge driving thermal convection (free convection); the co ...
... and thermal coupling. Mechanical coupling (viscous traction) between the subducting slab and the base of the mantle wedge drives corner flow [McKenzie, 1969], a type of forced convection. The subducting slab also cools the base of the mantle wedge driving thermal convection (free convection); the co ...
here - W. Steven Holbrook
... native to arcs and therefore must be acquired during later tectonic and magmatic events. These differences in internal structure and bulk composition indicate that, if island arcs serve as building blocks of continental crust, their properties are significantly altered during or after accretion to a ...
... native to arcs and therefore must be acquired during later tectonic and magmatic events. These differences in internal structure and bulk composition indicate that, if island arcs serve as building blocks of continental crust, their properties are significantly altered during or after accretion to a ...
The Imbert Formation of northern Hispaniola: a tectono
... Received: 11 May 2015 – Published in Solid Earth Discuss.: 26 June 2015 Revised: 22 September 2015 – Accepted: 8 December 2015 – Published: 15 January 2016 ...
... Received: 11 May 2015 – Published in Solid Earth Discuss.: 26 June 2015 Revised: 22 September 2015 – Accepted: 8 December 2015 – Published: 15 January 2016 ...
seamount subduction and earthquakes
... region between the trench axis and the volcanic arc. Seamount subduction may also influence the degree of coupling between the overriding and subducting plates and may affect the seismicity, especially the size and frequency of large earthquakes (Kelleher and McCann, 1976). Recently, Nishizawa et al ...
... region between the trench axis and the volcanic arc. Seamount subduction may also influence the degree of coupling between the overriding and subducting plates and may affect the seismicity, especially the size and frequency of large earthquakes (Kelleher and McCann, 1976). Recently, Nishizawa et al ...
Triggering of the largest Deccan eruptions by the Chicxulub impact
... Chicxulub impact, together with a particularly voluminous and apparently brief eruptive pulse toward the end of the “main-stage” eruptions of the Deccan continental flood basalt province suggest that these three events may have occurred within less than about a hundred thousand years of each other. ...
... Chicxulub impact, together with a particularly voluminous and apparently brief eruptive pulse toward the end of the “main-stage” eruptions of the Deccan continental flood basalt province suggest that these three events may have occurred within less than about a hundred thousand years of each other. ...
Thermal Structure due to Solid-State Flow in the Mantle
... with petrologic constraints. One caveat is that trajectories of melt migration beneath an arc might not be vertical. Porous flow might lead to melt migration vectors that ascend diagonally toward the wedge corner either due to pressure gradients in the mantle flow [Spiegelman and McKenzie, 1987; Phi ...
... with petrologic constraints. One caveat is that trajectories of melt migration beneath an arc might not be vertical. Porous flow might lead to melt migration vectors that ascend diagonally toward the wedge corner either due to pressure gradients in the mantle flow [Spiegelman and McKenzie, 1987; Phi ...
Origin and Evolution of the Western Snake River Plain
... elevation about 3,200 feet above sea level. The southern limit of this plateau is an escarpment overlooking the current drainage of the Snake River, just upstream from its confluence with the Bruneau River; the elevation at river level is about 2,800 feet. The plateau is truncated along its northern ...
... elevation about 3,200 feet above sea level. The southern limit of this plateau is an escarpment overlooking the current drainage of the Snake River, just upstream from its confluence with the Bruneau River; the elevation at river level is about 2,800 feet. The plateau is truncated along its northern ...
Review of Late Jurassic-early Miocene sedimentation and plate
... during construction of the emergent arc. They were not intensely overprinted by low-grade metamorphic phases, so evidently were stored at rather shallow upper mantle depths as indicated by the common spatial association of HP/LT blocks with serpentinized peridotites—never with deepseated xenoliths o ...
... during construction of the emergent arc. They were not intensely overprinted by low-grade metamorphic phases, so evidently were stored at rather shallow upper mantle depths as indicated by the common spatial association of HP/LT blocks with serpentinized peridotites—never with deepseated xenoliths o ...
Thermal structure of the Costa Rica – Nicaragua subduction zone
... (e.g., NE Japan, Izu-Bonin) results in subducting plates that are ∼300 ◦ C cooler than subduction zones characterized by modest convergence and young incoming lithosphere (e.g., SW Japan, Cascadia) (Peacock and Wang, 1999). Cooler subducting plates correlate with deeper Wadati-Benioff seismicity and ...
... (e.g., NE Japan, Izu-Bonin) results in subducting plates that are ∼300 ◦ C cooler than subduction zones characterized by modest convergence and young incoming lithosphere (e.g., SW Japan, Cascadia) (Peacock and Wang, 1999). Cooler subducting plates correlate with deeper Wadati-Benioff seismicity and ...
mud diapirs and mud volcanoes in depressions of java to madura
... Mud diapir and mud volcano are piercement structures showing release of overpressured sediments piercing upward from subsurface to the Earth’s surface due to buoyancy and differential pressure. These structures occur in “elisional” basin mainly characterized by rapid deposition of thick young sedime ...
... Mud diapir and mud volcano are piercement structures showing release of overpressured sediments piercing upward from subsurface to the Earth’s surface due to buoyancy and differential pressure. These structures occur in “elisional” basin mainly characterized by rapid deposition of thick young sedime ...
Geologic mapping of the Chaac-Camaxtli region of Io from Galileo
... maps were used to identify the range of volcano morphologies (e.g., shield volcanoes, pit craters, calderas, cones) and eruption products (e.g., lava flows, pyroclastic blankets) on Io, to interpret the colors of volcanic features relative to possible magma compositions, and to infer the sequence of ...
... maps were used to identify the range of volcano morphologies (e.g., shield volcanoes, pit craters, calderas, cones) and eruption products (e.g., lava flows, pyroclastic blankets) on Io, to interpret the colors of volcanic features relative to possible magma compositions, and to infer the sequence of ...
Thermal and metamorphic environment of subduction zone episodic
... heat flow measurements. Note that the choice of mantle rheology does not significantly affect the temperatures calculated for the shallow fore arc, unless flow in the mantle wedge corner were to extend updip to depths <50 km, which would be inconsistent with fore-arc heat flow observations [e.g., Wi ...
... heat flow measurements. Note that the choice of mantle rheology does not significantly affect the temperatures calculated for the shallow fore arc, unless flow in the mantle wedge corner were to extend updip to depths <50 km, which would be inconsistent with fore-arc heat flow observations [e.g., Wi ...
the karoo volcanic rocks and related intrusions in
... Volcanic rocks and related hypabyssal intrusions of the Mesozoic Karoo large igneous province are wide-spread in southern and central Mozambique and form mesa-like ridges or wide, fertile valleys, depending on the nature and composition of the volcanic flows. The 600 km long, north-south oriented Leb ...
... Volcanic rocks and related hypabyssal intrusions of the Mesozoic Karoo large igneous province are wide-spread in southern and central Mozambique and form mesa-like ridges or wide, fertile valleys, depending on the nature and composition of the volcanic flows. The 600 km long, north-south oriented Leb ...
IJNlliEl\$.lTY OF ICl:`LAND - Nordic Volcanological Center
... between deflations, which last from a few hours to 20 days. The rate of deflation varies greatly from one deflation event to another (Bjornsson et al. 1979, Tryggvason 1980). Widening of the fissure swarm associated with opening of new and old fissures, vertical fault displacements, earthquake swarm ...
... between deflations, which last from a few hours to 20 days. The rate of deflation varies greatly from one deflation event to another (Bjornsson et al. 1979, Tryggvason 1980). Widening of the fissure swarm associated with opening of new and old fissures, vertical fault displacements, earthquake swarm ...
Cascade Volcanoes
This article is for the volcanic arc. For the namesake mountain range see Cascade Range.The Cascade Volcanoes (also known as the Cascade Volcanic Arc or the Cascade Arc) are a number of volcanoes in a volcanic arc in western North America, extending from southwestern British Columbia through Washington and Oregon to Northern California, a distance of well over 700 miles (1,100 km). The arc has formed due to subduction along the Cascadia subduction zone. Although taking its name from the Cascade Range, this term is a geologic grouping rather than a geographic one, and the Cascade Volcanoes extend north into the Coast Mountains, past the Fraser River which is the northward limit of the Cascade Range proper.Some of the major cities along the length of the arc include Portland, Seattle, and Vancouver, and the population in the region exceeds 10,000,000. All could be potentially affected by volcanic activity and great subduction-zone earthquakes along the arc. Because the population of the Pacific Northwest is rapidly increasing, the Cascade volcanoes are some of the most dangerous, due to their eruptive history and potential for future eruptions, and because they are underlain by weak, hydrothermally altered volcanic rocks that are susceptible to failure. Consequently, Mount Rainier is one of the Decade Volcanoes identified by the International Association of Volcanology and Chemistry of the Earth's Interior (IAVCEI) as being worthy of particular study, due to the danger it poses to Seattle and Tacoma. Many large, long-runout landslides originating on Cascade volcanoes have inundated valleys tens of kilometers from their sources, and some of the inundated areas now support large populations.The Cascade Volcanoes are part of the Pacific Ring of Fire, the ring of volcanoes and associated mountains around the Pacific Ocean. All of the known historic eruptions in the contiguous United States have been from the Cascade Volcanoes. Two most recent were Lassen Peak in 1914 to 1921 and a major eruption of Mount St. Helens in 1980. It is also the site of Canada's most recent major eruption about 2,350 years ago at the Mount Meager volcanic complex.