Roberts et al., 2013, Basin Modeling
... break-up, leading to prediction of heat-flow history; •• identify (i) areas of stretched continental crust, (ii) areas of highly attenuated continental crust within the ocean–continent transition (OCT), (iii) the location of the continent–ocean boundary (COB), (iv) areas of oceanic crust; •• assess ...
... break-up, leading to prediction of heat-flow history; •• identify (i) areas of stretched continental crust, (ii) areas of highly attenuated continental crust within the ocean–continent transition (OCT), (iii) the location of the continent–ocean boundary (COB), (iv) areas of oceanic crust; •• assess ...
Three-dimensional crustal structure of the Mariana island arc from
... Mariana Trough continues at the present day [Fryer, 1995], and is separating the West Mariana Ridge from the presently active Mariana arc that formed 3– 4 Ma ago 40 km west of the remnant Eocene arc [Stern et al., 2003]. Along the Mariana segment, volcanic islands are found only in the central regi ...
... Mariana Trough continues at the present day [Fryer, 1995], and is separating the West Mariana Ridge from the presently active Mariana arc that formed 3– 4 Ma ago 40 km west of the remnant Eocene arc [Stern et al., 2003]. Along the Mariana segment, volcanic islands are found only in the central regi ...
Occurrences of disseminated sulphides from
... pyrites and thus related with low-temperature hydrothermal activity. Close to the dredge location, tectonic activity around the Vityaz megamullion might have promoted hydrothermal circulation ...
... pyrites and thus related with low-temperature hydrothermal activity. Close to the dredge location, tectonic activity around the Vityaz megamullion might have promoted hydrothermal circulation ...
Reference crust-mantle density contrast beneath Antarctica based
... rough topography, continental ice sheet and variable geological structure (mainly large sediment deposits). The three largest mountain ranges on the Antarctic continent are the Transantarctic Mountains, the West and East Antarctica ranges. The Transantarctic Mountains is formed by a mountain range e ...
... rough topography, continental ice sheet and variable geological structure (mainly large sediment deposits). The three largest mountain ranges on the Antarctic continent are the Transantarctic Mountains, the West and East Antarctica ranges. The Transantarctic Mountains is formed by a mountain range e ...
Crust and upper mantle structure beneath the Pacific Northwest from
... [2] Since the mid-Miocene, the Pacific Northwest U.S.A. (PNW) has been subjected to widespread volcanic activity that is not limited to ongoing Cascade arc volcanism (where eruptions began in the region of the present-day arc ca. 45–50 Ma [Madsen et al., 2006]). Voluminous flood basalt volcanism beg ...
... [2] Since the mid-Miocene, the Pacific Northwest U.S.A. (PNW) has been subjected to widespread volcanic activity that is not limited to ongoing Cascade arc volcanism (where eruptions began in the region of the present-day arc ca. 45–50 Ma [Madsen et al., 2006]). Voluminous flood basalt volcanism beg ...
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... that extensional stresses persist beyond the lifespans of individual BABs. These observations suggest that something other than the duration of extensional stress regimes in the upper plate is important for determining BAB lifespans. The supply of hydrated mantle, which rises beneath the BAB spreadi ...
... that extensional stresses persist beyond the lifespans of individual BABs. These observations suggest that something other than the duration of extensional stress regimes in the upper plate is important for determining BAB lifespans. The supply of hydrated mantle, which rises beneath the BAB spreadi ...
Ancient recycled mantle lithosphere in the Hawaiian plume: Osmium
... Generation of basaltic oceanic crust at divergent plate boundaries (i.e. mid oceanic ridges) and recycling of the lithospheric plate back into the Earth's mantle via subduction at convergent plate boundaries play a principle role in the generation of long-lived chemical and isotopic heterogeneities ...
... Generation of basaltic oceanic crust at divergent plate boundaries (i.e. mid oceanic ridges) and recycling of the lithospheric plate back into the Earth's mantle via subduction at convergent plate boundaries play a principle role in the generation of long-lived chemical and isotopic heterogeneities ...
workshop report
... hypotheses can be tested by drilling, so we will focus solely on the role of subduction in creating juvenile crust. The presence of significant volume of middle crust with 6.0-6.8 km/s seismic velocities throughout the entire IBM arc (Calvert et al., 2008; Kodaira et al., 2007a,b; Kodaira et al., 20 ...
... hypotheses can be tested by drilling, so we will focus solely on the role of subduction in creating juvenile crust. The presence of significant volume of middle crust with 6.0-6.8 km/s seismic velocities throughout the entire IBM arc (Calvert et al., 2008; Kodaira et al., 2007a,b; Kodaira et al., 20 ...
Mechanics of active magmatic intraplating in the Rio Grande Rift
... scenes most affected by the atmospheric noise [Rivet and Fialko, 2007]. LOS velocities toward the satellite are taken to be positive. Dome‐like uplift at a rate of 2–3 mm yr−1 can be clearly seen in each of these stacks in the region corresponding approximately with the intersection of the two seism ...
... scenes most affected by the atmospheric noise [Rivet and Fialko, 2007]. LOS velocities toward the satellite are taken to be positive. Dome‐like uplift at a rate of 2–3 mm yr−1 can be clearly seen in each of these stacks in the region corresponding approximately with the intersection of the two seism ...
- Wiley Online Library
... thrust fault vergence and decreased P-wave velocities suggest the presence of a subduction sediment channel 1 km in thickness under the coast [Gulick et al., 1998; Trehu et al., 2012; McNeill et al., 2013]. Sediment compaction and clay dehydration can release large amounts of fluids to distances app ...
... thrust fault vergence and decreased P-wave velocities suggest the presence of a subduction sediment channel 1 km in thickness under the coast [Gulick et al., 1998; Trehu et al., 2012; McNeill et al., 2013]. Sediment compaction and clay dehydration can release large amounts of fluids to distances app ...
2014-Wannamaker-Casc.. - University of Alberta
... thrust fault vergence and decreased P-wave velocities suggest the presence of a subduction sediment channel 1 km in thickness under the coast [Gulick et al., 1998; Trehu et al., 2012; McNeill et al., 2013]. Sediment compaction and clay dehydration can release large amounts of fluids to distances app ...
... thrust fault vergence and decreased P-wave velocities suggest the presence of a subduction sediment channel 1 km in thickness under the coast [Gulick et al., 1998; Trehu et al., 2012; McNeill et al., 2013]. Sediment compaction and clay dehydration can release large amounts of fluids to distances app ...
The structure and dynamics of the mantle wedge
... Subduction zones are the dominant tectonic features of the Earth. They form the location of the major underthrusting earthquakes, explosive arc volcanism and are the only sites of deep earthquakes in the Earth’s mantle. The role of subduction zones in the plate tectonic framework is reasonably well ...
... Subduction zones are the dominant tectonic features of the Earth. They form the location of the major underthrusting earthquakes, explosive arc volcanism and are the only sites of deep earthquakes in the Earth’s mantle. The role of subduction zones in the plate tectonic framework is reasonably well ...
Rhenium^Osmium Isotope and Platinum
... rock differentiation series from dunite cumulates, peridotites, pyroxenites, and gabbros, to granophyres. Second, it is one of the most ultramafic large layered intrusions so far recognized on Earth and has been considered to be related in space and time to the extensive 127 Ga giant Mackenzie dyke ...
... rock differentiation series from dunite cumulates, peridotites, pyroxenites, and gabbros, to granophyres. Second, it is one of the most ultramafic large layered intrusions so far recognized on Earth and has been considered to be related in space and time to the extensive 127 Ga giant Mackenzie dyke ...
LOW RES
... orthogonal convergence rates determined using the NUVEL1A plate motion model [DeMets et al., 1994]. For the mantle wedge, we use a simple dynamical flow model of Newtonian viscous corner flow [Batchelor, 1967] driven by a no-slip boundary condition along the top of the subducting plate. Mantle-wedge ...
... orthogonal convergence rates determined using the NUVEL1A plate motion model [DeMets et al., 1994]. For the mantle wedge, we use a simple dynamical flow model of Newtonian viscous corner flow [Batchelor, 1967] driven by a no-slip boundary condition along the top of the subducting plate. Mantle-wedge ...
EAST AFRICAN RIFT SYSTEM
... phonolites to 3) and 4) pervasive partial melting of the lower crust due to lowering of the central rift segment into the heated zone causing trachyte outpourings (Bailey 1974). The formation of rift fractures initiates magmatism, the volume and composition of the volcanics being controlled by the o ...
... phonolites to 3) and 4) pervasive partial melting of the lower crust due to lowering of the central rift segment into the heated zone causing trachyte outpourings (Bailey 1974). The formation of rift fractures initiates magmatism, the volume and composition of the volcanics being controlled by the o ...
EAST AFRICAN RIFT SYSTEM
... phonolites to 3) and 4) pervasive partial melting of the lower crust due to lowering of the central rift segment into the heated zone causing trachyte outpourings (Bailey 1974). The formation of rift fractures initiates magmatism, the volume and composition of the volcanics being controlled by the o ...
... phonolites to 3) and 4) pervasive partial melting of the lower crust due to lowering of the central rift segment into the heated zone causing trachyte outpourings (Bailey 1974). The formation of rift fractures initiates magmatism, the volume and composition of the volcanics being controlled by the o ...
Low seismic velocity layers in the Earth`s crust beneath Eastern
... Analysis of teleseismic receiver functions at digital stations along the Bratsk – Irkutsk – Ulanbaatar – Undurshil profile suggests that low-velocity layers in the Earth’s crust exist not only beneath the Baikal rift zone, where such a layer was found earlier by Deep Seismic Sounding (DSS), but also ...
... Analysis of teleseismic receiver functions at digital stations along the Bratsk – Irkutsk – Ulanbaatar – Undurshil profile suggests that low-velocity layers in the Earth’s crust exist not only beneath the Baikal rift zone, where such a layer was found earlier by Deep Seismic Sounding (DSS), but also ...
Evolution of the Tyrrhenian Sea-Calabrian Arc system: The past and
... approximately E-W when extension was active in the Cornaglia terrace and in the Vavilov basin, and then rotated to SE-NW during the formation of the Marsili basin (SARTORI, 2003). Extension rates averaged over the last 10 Ma are 40-50 km/Ma (PATACCA et alii, 1990; FACCENNA et alii, 1996; FACCENNA et ...
... approximately E-W when extension was active in the Cornaglia terrace and in the Vavilov basin, and then rotated to SE-NW during the formation of the Marsili basin (SARTORI, 2003). Extension rates averaged over the last 10 Ma are 40-50 km/Ma (PATACCA et alii, 1990; FACCENNA et alii, 1996; FACCENNA et ...
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... parallel belts: (1) Outer Zagros Ophiolitic Belt (OB) and (2) Inner Zagros Ophiolitic Belt (IB). These belts contain complete (if disrupted) ophiolites with well-preserved mantle and crustal sequences. Mantle sequences include tectonized harzburgite and rare ultramafic–mafic cumulates as well as iso ...
... parallel belts: (1) Outer Zagros Ophiolitic Belt (OB) and (2) Inner Zagros Ophiolitic Belt (IB). These belts contain complete (if disrupted) ophiolites with well-preserved mantle and crustal sequences. Mantle sequences include tectonized harzburgite and rare ultramafic–mafic cumulates as well as iso ...
Protoridge_Three-Dimensional Seismic Imaging of a
... region ;1000 km in diameter are thought to reflect the impact of a plume head beneath the continent (e.g., Pik et al., 1999). Geophysical evidence indicates a deep-seated thermal anomaly consistent with the presence of a plume, with anomalously low P-wave velocities from depths of 650 km beneath Afa ...
... region ;1000 km in diameter are thought to reflect the impact of a plume head beneath the continent (e.g., Pik et al., 1999). Geophysical evidence indicates a deep-seated thermal anomaly consistent with the presence of a plume, with anomalously low P-wave velocities from depths of 650 km beneath Afa ...
101 Questions and Answers Concerning
... Is water’s large heat of vaporization also a problem for CPT, as it is for canopy models? Does accumulating basalt from a subducting plate buoy up the adjacent continent edge? How could the Atlantic open and close with no effect on the Aleutian-Siberian platform? How can fossils be employed to corre ...
... Is water’s large heat of vaporization also a problem for CPT, as it is for canopy models? Does accumulating basalt from a subducting plate buoy up the adjacent continent edge? How could the Atlantic open and close with no effect on the Aleutian-Siberian platform? How can fossils be employed to corre ...
the caribbean plate and the question of its formation
... to that group of magmatic island arcs formed on oceanic crust. Subduction related magmatism occurred since the Middle Cretaceous to the Middle or Late Eocene. The Aves Ridge arc started its activity at the beginning of the Late Cretaceous and ceased in the Early Palaeocene. After that time a calcare ...
... to that group of magmatic island arcs formed on oceanic crust. Subduction related magmatism occurred since the Middle Cretaceous to the Middle or Late Eocene. The Aves Ridge arc started its activity at the beginning of the Late Cretaceous and ceased in the Early Palaeocene. After that time a calcare ...
The nature of the crust beneath the Afar triple junction: Evidence
... are up to 5 km thick in Afar (Berckhemer profile 4 and 5, Figure 1) [Makris and Ginzburg, 1987], and can include considerable evaporite deposits [Behle et al., 1975]. Below this layer, the upper crust is interpreted by previous authors as Pan‐African Precambrian crystalline basement in the MER and A ...
... are up to 5 km thick in Afar (Berckhemer profile 4 and 5, Figure 1) [Makris and Ginzburg, 1987], and can include considerable evaporite deposits [Behle et al., 1975]. Below this layer, the upper crust is interpreted by previous authors as Pan‐African Precambrian crystalline basement in the MER and A ...
Aseismic zone and earthquake segmentation associated with a
... were mainly of thrust type. We have relocated all the earthquakes from January 1964 to January 2008 (see Methods section). The seismicity mainly lies beneath the forearc basin, suggesting the deep segment of the subducting plate is active. The 2000 earthquake is in a region showing high seismic acti ...
... were mainly of thrust type. We have relocated all the earthquakes from January 1964 to January 2008 (see Methods section). The seismicity mainly lies beneath the forearc basin, suggesting the deep segment of the subducting plate is active. The 2000 earthquake is in a region showing high seismic acti ...
1 The role of the mantle wedge in subduction zone dynamics and
... Heatflow, topography, gravity and geoid The heat flow variations across subduction zones provide important constraints on the thermal structure. In general the heatflow in the fore arc is low due to the subduction of cold lithosphere, moderately high in the back arc and high in the volcanic arc (e.g ...
... Heatflow, topography, gravity and geoid The heat flow variations across subduction zones provide important constraints on the thermal structure. In general the heatflow in the fore arc is low due to the subduction of cold lithosphere, moderately high in the back arc and high in the volcanic arc (e.g ...
Baltic Shield
The Baltic Shield (sometimes referred to as the Fennoscandian Shield) is located in Fennoscandia (Norway, Sweden and Finland), northwest Russia and under the Baltic Sea. The Baltic Shield is defined as the exposed Precambrian northwest segment of the East European Craton. It is composed mostly of Archean and Proterozoic gneisses and greenstones which have undergone numerous deformations through tectonic activity (see Geology of Fennoscandia map [1]). The Baltic Shield contains the oldest rocks of the European continent. The lithospheric thickness is about 200-300 km. During the Pleistocene epoch, great continental ice sheets scoured and depressed the shield's surface, leaving a thin covering of glacial material and innumerable lakes and streams. The Baltic Shield is still rebounding today following the melting of the thick glaciers during the Quaternary Period.