Geochemistry of Jurassic Oceanic Crust beneath
... (DSDP) Site 397, ~100 km southeast of Gran Canaria. The igneous crustal samples (layers 2 and 3) occur as cobbles within a Miocene (~14 Ma) fanglomerate exposed at the bottom of Barranco (Canyon) de Balos in the SE portion of Gran Canaria, and are interpreted to have been brought to the surface in p ...
... (DSDP) Site 397, ~100 km southeast of Gran Canaria. The igneous crustal samples (layers 2 and 3) occur as cobbles within a Miocene (~14 Ma) fanglomerate exposed at the bottom of Barranco (Canyon) de Balos in the SE portion of Gran Canaria, and are interpreted to have been brought to the surface in p ...
Archaean plate tectonics revisited 1. Heat flow, spreading rate, and
... propose mechanisms by which the planetary ...
... propose mechanisms by which the planetary ...
VEIN-STOCKWORK TIN, TUNGSTEN
... Metal zoning is common i n many vein-stockwork tin and tungsten deposits and districts. In the tin-copper deposits of Cornwall, for example, tin (&tungsten) veins occur closest to, and commonly within, associated granite bodies; copper and lead-zinc veins are distributed above and outward from the t ...
... Metal zoning is common i n many vein-stockwork tin and tungsten deposits and districts. In the tin-copper deposits of Cornwall, for example, tin (&tungsten) veins occur closest to, and commonly within, associated granite bodies; copper and lead-zinc veins are distributed above and outward from the t ...
Wadhwan Formation of Western India
... According to Cannon et al. (1981) and Tankard et al. (1982) the beginning of plate separation in other parts of the Gondwana land during Jurassic and Early Cretaceous was marked by the formation of pericratonic rift basins which were similar to the pericratonic rifts (Kutch and Saurashtra) of India. ...
... According to Cannon et al. (1981) and Tankard et al. (1982) the beginning of plate separation in other parts of the Gondwana land during Jurassic and Early Cretaceous was marked by the formation of pericratonic rift basins which were similar to the pericratonic rifts (Kutch and Saurashtra) of India. ...
the geology of the volcanic island jan mayen arctic ocean
... The island of Jan Mayen is built up by potassic alkaline (dominantly basic) volcanic rocks. The volcanism is fed by a NE trending fissure system. On Nord-Jan eruptions have mostly occurred through the central crater of the volcanic cone Beerenberg and short radial fissures or single craters on its f ...
... The island of Jan Mayen is built up by potassic alkaline (dominantly basic) volcanic rocks. The volcanism is fed by a NE trending fissure system. On Nord-Jan eruptions have mostly occurred through the central crater of the volcanic cone Beerenberg and short radial fissures or single craters on its f ...
geology
... Magma types: chemical composition, origin and distribution of The chemical compositions of rocks and magmas should be expressed in terms of oxides. basaltic, andesitic and granitic magmas; tectonic significance of It should be strongly pointed out, however, that the appearance of an oxide in an anal ...
... Magma types: chemical composition, origin and distribution of The chemical compositions of rocks and magmas should be expressed in terms of oxides. basaltic, andesitic and granitic magmas; tectonic significance of It should be strongly pointed out, however, that the appearance of an oxide in an anal ...
Geology and geochronology of mineral deposits in the Biga
... Folds (Gondwana realm; Fig. 1, small inset). These fourfold tectonic units of Turkey have been modified by many later workers (Gorur, 1998; Okay and Tuysuz, 1999; Sengor, 1984; Sengor and Yilmaz, 1981; Sengor et al., 1980, 1984; Stampfli, 2000) and have been subdivided into many different tectonic zon ...
... Folds (Gondwana realm; Fig. 1, small inset). These fourfold tectonic units of Turkey have been modified by many later workers (Gorur, 1998; Okay and Tuysuz, 1999; Sengor, 1984; Sengor and Yilmaz, 1981; Sengor et al., 1980, 1984; Stampfli, 2000) and have been subdivided into many different tectonic zon ...
garwin_et_al_2005 Au-Cu Cenozoic magmatic arcs SE Asia
... forearc and backarc sides of the northern part of the arc, respectively. This intrusive activity was followed by Pliocene and Quaternary calc-alkaline andesite volcanism, which is associated with rhyolite and dacite in the backarc (Karakida et al., 1992). Paleomagnetic data (Kodama et al., 1995) and ...
... forearc and backarc sides of the northern part of the arc, respectively. This intrusive activity was followed by Pliocene and Quaternary calc-alkaline andesite volcanism, which is associated with rhyolite and dacite in the backarc (Karakida et al., 1992). Paleomagnetic data (Kodama et al., 1995) and ...
The tectonic regime along the Andes: Present
... the crustal removal of subduction erosion is taken into consideration (von Huene and Scholl 1991; Ranero and von Huene 2000). Some second-order controls in the kinematics, such as oceanic ridge collisions or fracture zone collisions, can be locally overimposed on the first-order control, yielding fo ...
... the crustal removal of subduction erosion is taken into consideration (von Huene and Scholl 1991; Ranero and von Huene 2000). Some second-order controls in the kinematics, such as oceanic ridge collisions or fracture zone collisions, can be locally overimposed on the first-order control, yielding fo ...
A Pictorial Guide to Metamorphic Rocks in the Field
... orientation as the cleavage and fractures in the upper part of the image. The central, quartz-rich layer has quartz veins (yellow arrows) that have approximately the same orientation as c leavage in the pelitic layers. The layers have been folded but here are stratigraphically right-side-up. Yes, y ...
... orientation as the cleavage and fractures in the upper part of the image. The central, quartz-rich layer has quartz veins (yellow arrows) that have approximately the same orientation as c leavage in the pelitic layers. The layers have been folded but here are stratigraphically right-side-up. Yes, y ...
Slayt 1
... Massif. It is represented by a great number of geothermal outlets, epithermal ore deposits and volcanic rocks from Middle Miocene to recent. Geothermal waters are related to faults which strike NW-SE and/or NE-SW diagonal to general strike of the rift zone of the Gediz. These faults are generated by ...
... Massif. It is represented by a great number of geothermal outlets, epithermal ore deposits and volcanic rocks from Middle Miocene to recent. Geothermal waters are related to faults which strike NW-SE and/or NE-SW diagonal to general strike of the rift zone of the Gediz. These faults are generated by ...
Michael John O`Hara. 22 February 1933
... Mike was a student at Peterhouse between 1952 and 1958, the first three years as an undergraduate and the final three as a postgraduate research student. Peterhouse is the oldest and smallest of the Cambridge colleges and the most traditional. It was to be immortalized in the novel Porterhouse blue ...
... Mike was a student at Peterhouse between 1952 and 1958, the first three years as an undergraduate and the final three as a postgraduate research student. Peterhouse is the oldest and smallest of the Cambridge colleges and the most traditional. It was to be immortalized in the novel Porterhouse blue ...
What controls the occurrence of shallow intraplate earthquakes? Yoshihisa Iio
... earthquake faults, despite the fact that stress at nearby plate boundaries is released quasi-periodically and is apparently not accumulated over the recurrence interval of interplate earthquakes? 2) Why do intraplate earthquakes occur far from the plate boundary region, even though strain rates decr ...
... earthquake faults, despite the fact that stress at nearby plate boundaries is released quasi-periodically and is apparently not accumulated over the recurrence interval of interplate earthquakes? 2) Why do intraplate earthquakes occur far from the plate boundary region, even though strain rates decr ...
high-sulphidation, epithermal-style
... a lithologically diverse complex of greenschist-facies subaerial flows and volcaniclastic rocks, the products of protracted and episodic, large-scale caldera-forming eruptions. The Marystown Group exhibits a continuum of compositions from basalt, through andesite and rhyodacite, to rhyolite, all of ...
... a lithologically diverse complex of greenschist-facies subaerial flows and volcaniclastic rocks, the products of protracted and episodic, large-scale caldera-forming eruptions. The Marystown Group exhibits a continuum of compositions from basalt, through andesite and rhyodacite, to rhyolite, all of ...
hal-insu.archives-ouvertes.fr - HAL
... *Correspondence to: [email protected] The relative contribution of crustal and mantle processes to surface deformation at convergent plate margins is still controversial. Conflicting models involving either extrusion mechanisms or slab rollback, in particular, were proposed to explain t ...
... *Correspondence to: [email protected] The relative contribution of crustal and mantle processes to surface deformation at convergent plate margins is still controversial. Conflicting models involving either extrusion mechanisms or slab rollback, in particular, were proposed to explain t ...
Adakitic magmas: modern analogues of Archaean granitoids
... 1995; Blais et al., 1997.. However, if plate tectoniclike processes operated, secular compositional changes in magmatism and tectonic regimes indicate that in detail, the processes were different from modern ones. Most of the differences result from greater Archaean heat production, inducing higher ...
... 1995; Blais et al., 1997.. However, if plate tectoniclike processes operated, secular compositional changes in magmatism and tectonic regimes indicate that in detail, the processes were different from modern ones. Most of the differences result from greater Archaean heat production, inducing higher ...
a short story about the geological history of the pamir
... Before the beginning of the collision between India and Eurasia in Late Eozean time a wide sedimentary basin, the Tadjik-Yarkand basin, occupied the region now covered by the Pamir. It extends over the whole Tadjik Depression to the Yarkand Depression at the western end of the Tarim basin. Late Cret ...
... Before the beginning of the collision between India and Eurasia in Late Eozean time a wide sedimentary basin, the Tadjik-Yarkand basin, occupied the region now covered by the Pamir. It extends over the whole Tadjik Depression to the Yarkand Depression at the western end of the Tarim basin. Late Cret ...
Geological framework and mineralization of Papua New Guinea
... The oblique collision zone between the Australian and Pacific plates is marked by the presence of several minor plates. The Woodlark Plate lies in the south-eastern part of the region, whereas the South Bismarck and Caroline Plates occupy the north-eastern and northern part of the region. The main c ...
... The oblique collision zone between the Australian and Pacific plates is marked by the presence of several minor plates. The Woodlark Plate lies in the south-eastern part of the region, whereas the South Bismarck and Caroline Plates occupy the north-eastern and northern part of the region. The main c ...
Rifting, Seafloor Spreading, and Extensional Tectonics
... sequences of redbeds, conglomerates, evaporites, and volcanics. A preserved inactive rift can also be called an unsuccessful rift, in that its existence reflects the occurrence of a rifting event that stopped before it succeeded in splitting a continent in two. Unsuccessful rifts that cut into crato ...
... sequences of redbeds, conglomerates, evaporites, and volcanics. A preserved inactive rift can also be called an unsuccessful rift, in that its existence reflects the occurrence of a rifting event that stopped before it succeeded in splitting a continent in two. Unsuccessful rifts that cut into crato ...
the orivesi granite batholith, southern central finland
... which are in general euhedral, but oval (and mantled) megacrysts occur. The granite is extracted as dimensional stone ("Cardinal Red"/"Crystal Rose") from the southwestern part of the batholith. Additional potential sites for dimension stone are identified in same part of the batholith. The Orivesi ...
... which are in general euhedral, but oval (and mantled) megacrysts occur. The granite is extracted as dimensional stone ("Cardinal Red"/"Crystal Rose") from the southwestern part of the batholith. Additional potential sites for dimension stone are identified in same part of the batholith. The Orivesi ...
Plate-Tectonics A review
... Similar rock types extend from one continent to the other The rocks are also of the same age COCLUSIONS - perhaps the two continents were once part of a single largest continent? Imtiyaz A. Parvez, C-MMACS ...
... Similar rock types extend from one continent to the other The rocks are also of the same age COCLUSIONS - perhaps the two continents were once part of a single largest continent? Imtiyaz A. Parvez, C-MMACS ...
Batholith tectonics: Formation and deformation of ghost stratigraphy
... may be the result of multiple events of magma emplacement, crystallization, and solidification, even where contacts between two units are gradational or not observed (e.g., Memeti et al., 2010). If a single mapped intrusion is constructed by multiple batches of solidifying magma over some duration, ...
... may be the result of multiple events of magma emplacement, crystallization, and solidification, even where contacts between two units are gradational or not observed (e.g., Memeti et al., 2010). If a single mapped intrusion is constructed by multiple batches of solidifying magma over some duration, ...
as PDF
... appropriate for retrieving the shapes of the slab in different subduction zones where most intensive seismic activity is concentrated. Other contrasted features in the earth having relations with volcanism, mantle plumes, can also be studied by regional tomography, but they are much harder objects t ...
... appropriate for retrieving the shapes of the slab in different subduction zones where most intensive seismic activity is concentrated. Other contrasted features in the earth having relations with volcanism, mantle plumes, can also be studied by regional tomography, but they are much harder objects t ...
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.