The rift-related mafic dyke complex of the Rohkunborri Nappe, Indre
... Nystuen 1985) of Late Proterozoic to Lower Cambrian sedimentary rocks within these thrust sheets have estab lished three informal units: a thick lower mainly fluviatile unit, a middle glacial unit (Varangian) and an upper fluviatile and shallow marine unit of Late Vendian to Early Cambrian age. In ...
... Nystuen 1985) of Late Proterozoic to Lower Cambrian sedimentary rocks within these thrust sheets have estab lished three informal units: a thick lower mainly fluviatile unit, a middle glacial unit (Varangian) and an upper fluviatile and shallow marine unit of Late Vendian to Early Cambrian age. In ...
Guidebook
... The Crystalline-Mesozoic Zone is built up of basement shearing nappes, each of them showing large developed metamorphic formations covered by a Mesozoic or Permo-Mesozoic sedimentary envelope. The nappes, of Meso-Cretaceous age, cover each other. They are (up/down) the Bucovinian Nappe, the Subbucov ...
... The Crystalline-Mesozoic Zone is built up of basement shearing nappes, each of them showing large developed metamorphic formations covered by a Mesozoic or Permo-Mesozoic sedimentary envelope. The nappes, of Meso-Cretaceous age, cover each other. They are (up/down) the Bucovinian Nappe, the Subbucov ...
Garnet: Common Mineral, Uncommonly Useful
... Science database begins) that include the “topic” of garnet. This places garnet (as a “topic”) behind only five other minerals or broad mineral groups that were searched for (clay, graphite, quartz, diamond, zeolite) and ahead of important and/or common minerals like feldspar, calcite, zircon, and o ...
... Science database begins) that include the “topic” of garnet. This places garnet (as a “topic”) behind only five other minerals or broad mineral groups that were searched for (clay, graphite, quartz, diamond, zeolite) and ahead of important and/or common minerals like feldspar, calcite, zircon, and o ...
Thrust-top basin formation along a suture
... ian to early Maastrichtian timing of this possible marine influence is within the range of the Bearpaw transgressive event of the Cordilleran foreland basin and allows for regional stratigraphic correlation of the Cantwell basin with other sedimentary basins in northwestern North America. (3) Struct ...
... ian to early Maastrichtian timing of this possible marine influence is within the range of the Bearpaw transgressive event of the Cordilleran foreland basin and allows for regional stratigraphic correlation of the Cantwell basin with other sedimentary basins in northwestern North America. (3) Struct ...
Doglioni et al Mantle wedge asymmetries and geochemical
... Along the first type, there generally is an upward flow of the asthenosphere in the hanging wall of the slab, whereas along the opposite second type, the mantle is pushed down due to the thickening of the lithosphere. The kinematics of W-directed subduction zones predict a much thicker asthenospheric ...
... Along the first type, there generally is an upward flow of the asthenosphere in the hanging wall of the slab, whereas along the opposite second type, the mantle is pushed down due to the thickening of the lithosphere. The kinematics of W-directed subduction zones predict a much thicker asthenospheric ...
投影片 1
... Phanerozoic than in the Proterozoic and Archean. This is probably due to the predominance of basaltic rift-related volcanism in the Archean, and the gradual trend towards more felsic, cooler volcanism as the Earth ages. ...
... Phanerozoic than in the Proterozoic and Archean. This is probably due to the predominance of basaltic rift-related volcanism in the Archean, and the gradual trend towards more felsic, cooler volcanism as the Earth ages. ...
The role of frictional strength on plate coupling at the subduction
... driving force for subduction. Slab pull is counteracted to some degree by frictional resistance between the two plates. This leads to the periodic accumulation of elastic stresses at the interface between the plates that are episodically released in large earthquakes. Hence, this interface is called ...
... driving force for subduction. Slab pull is counteracted to some degree by frictional resistance between the two plates. This leads to the periodic accumulation of elastic stresses at the interface between the plates that are episodically released in large earthquakes. Hence, this interface is called ...
The nature of the crust beneath the Afar triple junction: Evidence
... plateau the upper crust has a thickness of ∼20–25 km [Makris and Ginzburg, 1987; Mackenzie et al., 2005; Maguire et al., 2006] (Figure 2). Makris and Ginzburg [1987] argue that, the thinned upper crust beneath Afar is not reflected in the lower crust, suggesting that the lower crust is thickened due ...
... plateau the upper crust has a thickness of ∼20–25 km [Makris and Ginzburg, 1987; Mackenzie et al., 2005; Maguire et al., 2006] (Figure 2). Makris and Ginzburg [1987] argue that, the thinned upper crust beneath Afar is not reflected in the lower crust, suggesting that the lower crust is thickened due ...
Receiver function images of the Hellenic subduction zone and
... structures in the forearc that have been identified as nearly vertical margins of forearc slivers the seismicity extends down to the subduction interface (Meier et al., 2007; Becker et al., 2009; Brüstle et al., 2014). The seismicity of the plate contact is only incompletely recorded due to the limi ...
... structures in the forearc that have been identified as nearly vertical margins of forearc slivers the seismicity extends down to the subduction interface (Meier et al., 2007; Becker et al., 2009; Brüstle et al., 2014). The seismicity of the plate contact is only incompletely recorded due to the limi ...
Fig. 1
... Despite the importance of continental breakup in plate tectonics, precisely how extensional processes such as brittle faulting, ductile plate stretching, and magma intrusion evolve in space and time during the development of new ocean basins remains poorly understood. The rifting of Arabia from Afri ...
... Despite the importance of continental breakup in plate tectonics, precisely how extensional processes such as brittle faulting, ductile plate stretching, and magma intrusion evolve in space and time during the development of new ocean basins remains poorly understood. The rifting of Arabia from Afri ...
Carbonate Facies and Sedimentation of the Klapanunggal
... environments. Framestone with very limited distribution as is found in the location of C1 and is associated with bafflestone is interpreted to be deposited on the lower slope environments. The wide distribution of Framestone Subfacies tends to indicate a reef crest environment. The Bafflestone Subfa ...
... environments. Framestone with very limited distribution as is found in the location of C1 and is associated with bafflestone is interpreted to be deposited on the lower slope environments. The wide distribution of Framestone Subfacies tends to indicate a reef crest environment. The Bafflestone Subfa ...
Magma Genesis and Mantle Dynamics at the Harrat Ash
... 2001; Shaw et al., 2003; Weinstein et al., 2006). The volcanic field varies in width between 200 and 300 km (Tarawneh et al., 2000) and the lava pile reaches a maximum thickness of 1.5 km and an altitude of ~800 m in Syria (Guba & Mustafa, 1988). The Dead Sea transform fault intersects the HAS at it ...
... 2001; Shaw et al., 2003; Weinstein et al., 2006). The volcanic field varies in width between 200 and 300 km (Tarawneh et al., 2000) and the lava pile reaches a maximum thickness of 1.5 km and an altitude of ~800 m in Syria (Guba & Mustafa, 1988). The Dead Sea transform fault intersects the HAS at it ...
Characterizing the hypersiliceous rocks of Belgium used in (pre
... of the original quartz grains and the cement phases, but also to reveal accessory luminescent minerals such as zircon, apatite and kyanite. The minerals rutile and tourmaline are known to show no luminescence and could therefore not be observed in the CCL study. The CCL emission colour of quartz is ...
... of the original quartz grains and the cement phases, but also to reveal accessory luminescent minerals such as zircon, apatite and kyanite. The minerals rutile and tourmaline are known to show no luminescence and could therefore not be observed in the CCL study. The CCL emission colour of quartz is ...
Rheology and strength of the lithosphere - Evgueni Burov
... long-term lithospheric strength is supported in the ductile or ductileeelastic regime, while it also maintains important brittle strength. Yet, at short seismic time scale (s), the entire lithosphere responds in elastic/brittleeelastic regime. Even though rock mechanics experiments provide important ...
... long-term lithospheric strength is supported in the ductile or ductileeelastic regime, while it also maintains important brittle strength. Yet, at short seismic time scale (s), the entire lithosphere responds in elastic/brittleeelastic regime. Even though rock mechanics experiments provide important ...
Lecture 19: Mantle Plumes - Earth and Atmospheric Sciences
... lithosphere with a distinctive isotopic signature and geochemists with a means of identifying continental lithosphere. In an earlier section, we discussed the hypothesis of McKenzie and O’Nions t h a t subcontinental lithosphere can delaminate and sink to the bottom of the mantle where it is incorpo ...
... lithosphere with a distinctive isotopic signature and geochemists with a means of identifying continental lithosphere. In an earlier section, we discussed the hypothesis of McKenzie and O’Nions t h a t subcontinental lithosphere can delaminate and sink to the bottom of the mantle where it is incorpo ...
Zuni–Bandera volcanism, Rio Grande, USA — Melt formation in
... geothermal gradients and/or the physical removal of the lithosphere due to thermal erosion by upwelling asthenosphere (Perry et al., 1987, 1988) and the increasingly refractory nature of the lithosphere with progressive melting and removal of volatile components emplaced during metasomatic events (M ...
... geothermal gradients and/or the physical removal of the lithosphere due to thermal erosion by upwelling asthenosphere (Perry et al., 1987, 1988) and the increasingly refractory nature of the lithosphere with progressive melting and removal of volatile components emplaced during metasomatic events (M ...
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... metamorphic rocks show faulted contacts with Shahre-Babak and Balvard–Baft ophiolites (Dimitrijevic, 1973). We think that the metamorphic conditions of SSZ rocks and emplacement between otherwise identical Zagros ophiolite belts supports the idea that these are exhumed subducted materials, which now ...
... metamorphic rocks show faulted contacts with Shahre-Babak and Balvard–Baft ophiolites (Dimitrijevic, 1973). We think that the metamorphic conditions of SSZ rocks and emplacement between otherwise identical Zagros ophiolite belts supports the idea that these are exhumed subducted materials, which now ...
Miocene and Early Pliocene Epithermal Gold
... tectonic environment of magma generation. The bimodal assemblage is a K-rich tholeiitic series formed during continental rifting. Rocks in the bimodal assemblage consist mostly of basalt to andesite and rhyolite compositions that generally contain anhydrous and reduced mineral assemblages (e.g., qua ...
... tectonic environment of magma generation. The bimodal assemblage is a K-rich tholeiitic series formed during continental rifting. Rocks in the bimodal assemblage consist mostly of basalt to andesite and rhyolite compositions that generally contain anhydrous and reduced mineral assemblages (e.g., qua ...
Stratigraphic Framework of the
... This paper describes the sedimentary rocks exposed on the Alaska Peninsula, as well as some interlayered volcanic and intrusive rocks. This sequence of rocks has a cumulative thickness of about 14,000 m, but most localities contain no more than 7,000-8,000 m. Locally the section is much thinner wher ...
... This paper describes the sedimentary rocks exposed on the Alaska Peninsula, as well as some interlayered volcanic and intrusive rocks. This sequence of rocks has a cumulative thickness of about 14,000 m, but most localities contain no more than 7,000-8,000 m. Locally the section is much thinner wher ...
DEEP STRUCTURE AND GEOPHYSICAL PROCESSES BENEATH
... the phase relations of mantle materials at these pressures, no further speculation is warranted. ...
... the phase relations of mantle materials at these pressures, no further speculation is warranted. ...
Continent–ocean transition and voluminous magmatic underplating
... were derived from forward traveltime modelling of land stations and ocean bottom hydrophone (OBH) recordings. For the first time, long deep seismic sounding transects off East Greenland provide a full insight into the crustal architecture of the transition from continental to oceanic crust. A mean r ...
... were derived from forward traveltime modelling of land stations and ocean bottom hydrophone (OBH) recordings. For the first time, long deep seismic sounding transects off East Greenland provide a full insight into the crustal architecture of the transition from continental to oceanic crust. A mean r ...
geologic map of orange county, north carolina
... Zhp/e – Mixed pyroclastic-epiclastics: Gray to green, felsic tuffs interlayed with mudstone, siltstone, and sandstone and distinctive immature, monomictic, conglomeratic sandstone to conglomerate containing subangular to angular clasts of plagioclase porphyritic dacite. Minor andesitic to basaltic l ...
... Zhp/e – Mixed pyroclastic-epiclastics: Gray to green, felsic tuffs interlayed with mudstone, siltstone, and sandstone and distinctive immature, monomictic, conglomeratic sandstone to conglomerate containing subangular to angular clasts of plagioclase porphyritic dacite. Minor andesitic to basaltic l ...
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... and (2) the professional who does not specialize in studying subduction zone processes but is interested or needs to know more about them. The fact that we have just celebrated the fiftieth anniversary of the introduction of the term “subduction” by Amstutz [1951] makes this overview all the more ap ...
... and (2) the professional who does not specialize in studying subduction zone processes but is interested or needs to know more about them. The fact that we have just celebrated the fiftieth anniversary of the introduction of the term “subduction” by Amstutz [1951] makes this overview all the more ap ...
subduction zones
... and (2) the professional who does not specialize in studying subduction zone processes but is interested or needs to know more about them. The fact that we have just celebrated the fiftieth anniversary of the introduction of the term “subduction” by Amstutz [1951] makes this overview all the more ap ...
... and (2) the professional who does not specialize in studying subduction zone processes but is interested or needs to know more about them. The fact that we have just celebrated the fiftieth anniversary of the introduction of the term “subduction” by Amstutz [1951] makes this overview all the more ap ...
Algoman orogeny
The Algoman orogeny, known as the Kenoran orogeny in Canada, was an episode of mountain-building (orogeny) during the Late Archean Eon that involved repeated episodes of continental collisions, compressions and subductions. The Superior province and the Minnesota River Valley terrane collided about 2,700 to 2,500 million years ago. The collision folded the Earth's crust and produced enough heat and pressure to metamorphose the rock. Blocks were added to the Superior province along a 1,200 km (750 mi) boundary that stretches from present-day eastern South Dakota into the Lake Huron area. The Algoman orogeny brought the Archaen Eon to a close, about 2,500 million years ago; it lasted less than 100 million years and marks a major change in the development of the earth’s crust.The Canadian shield contains belts of metavolcanic and metasedimentary rocks formed by the action of metamorphism on volcanic and sedimentary rock. The areas between individual belts consist of granites or granitic gneisses that form fault zones. These two types of belts can be seen in the Wabigoon, Quetico and Wawa subprovinces; the Wabigoon and Wawa are of volcanic origin and the Quetico is of sedimentary origin. These three subprovinces lie linearly in southwestern- to northeastern-oriented belts about 140 km (90 mi) wide on the southern portion of the Superior Province.The Slave province and portions of the Nain province were also affected. Between about 2,000 and 1,700 million years ago these combined with the Sask and Wyoming cratons to form the first supercontinent, the Kenorland supercontinent.