Modification of the Continental Crust by Subduction Zone
... fundamental phenomena in global tectonics: subduction of an oceanic plate beneath a more buoyant continental plate. The subduction of an oceanic plate results in recycling of crustal material into the convecting mantle, partial melting, and primary basalt production. Moreover, during passage through ...
... fundamental phenomena in global tectonics: subduction of an oceanic plate beneath a more buoyant continental plate. The subduction of an oceanic plate results in recycling of crustal material into the convecting mantle, partial melting, and primary basalt production. Moreover, during passage through ...
Huismans
... rift, thereby filling basins in P and S during both synrift phases but leaving D underfilled, as in the dynamical models (Fig. 2). Sediments, once deposited, will experience and record extension depending on whether or not stretching of the underlying crust continues. An important test of the model ...
... rift, thereby filling basins in P and S during both synrift phases but leaving D underfilled, as in the dynamical models (Fig. 2). Sediments, once deposited, will experience and record extension depending on whether or not stretching of the underlying crust continues. An important test of the model ...
eastern european alpine system and the carpathian
... of the continental fragments indicate they were considerably larger than their present size and had different shapes. Convergence of continental fragments began in the Late Jurassic by subduction of oceanic crust, but upon complete disappearance of oceanic crust, convergence continued with subductio ...
... of the continental fragments indicate they were considerably larger than their present size and had different shapes. Convergence of continental fragments began in the Late Jurassic by subduction of oceanic crust, but upon complete disappearance of oceanic crust, convergence continued with subductio ...
What drives orogeny in the Andes?
... Andes model. However, if we additionally use the mechanically stronger thin-crust (35–40 km) initial model instead of the thick-crust (40– 45 km) model, the tectonic shortening at 30 m.y. model time reduces to "40 km, which matches the situation in the southern Andes well (Fig. 4, curve indicated by ...
... Andes model. However, if we additionally use the mechanically stronger thin-crust (35–40 km) initial model instead of the thick-crust (40– 45 km) model, the tectonic shortening at 30 m.y. model time reduces to "40 km, which matches the situation in the southern Andes well (Fig. 4, curve indicated by ...
Evolution of early continental crust
... rocks that contain similar isotopic ratios as the DM are called juvenile, while rocks enriched in initial isotopic ratios are classified as evolved and contain a component of the older crust. The Nd-isotopic composition of Archaean rocks can thus help in constraining the geochemical characteristics ...
... rocks that contain similar isotopic ratios as the DM are called juvenile, while rocks enriched in initial isotopic ratios are classified as evolved and contain a component of the older crust. The Nd-isotopic composition of Archaean rocks can thus help in constraining the geochemical characteristics ...
crust - National Geographic Society
... Earth’s layers constantly interact with each other, and the crust and upper portion of the mantle are part of a single geologic unit called the lithosphere. The lithosphere’s depth varies, and the Mohorovicic discontinuity (the Moho)—the boundary between the mantle and crust—does not exist at a unif ...
... Earth’s layers constantly interact with each other, and the crust and upper portion of the mantle are part of a single geologic unit called the lithosphere. The lithosphere’s depth varies, and the Mohorovicic discontinuity (the Moho)—the boundary between the mantle and crust—does not exist at a unif ...
LITHOGEOCHEMISTRY OF ULTRAMAFIC, GABBROIC AND
... belt, which stretches latitudinally across the southern Superior Province, and consist predominantly of metagreywacke sequences intruded by granite and tonalite. Most of the Superior Province formed between 3.0 and 2.65 Ga and the subprovinces are considered to demarcate amalgamated volcanic arcs, s ...
... belt, which stretches latitudinally across the southern Superior Province, and consist predominantly of metagreywacke sequences intruded by granite and tonalite. Most of the Superior Province formed between 3.0 and 2.65 Ga and the subprovinces are considered to demarcate amalgamated volcanic arcs, s ...
Cretaceous–early Tertiary arc and fore
... Abstract: Halmahera is a K-shaped island located at the junction of several major arc-trench systems of the western Pacific-eastern Indonesia region. Western Halmahera is an active volcanic arc above a zone of intenseseismicitywhichcharacterizesthenorthMoluccaSea.EasternHalmaherahasa basement of dis ...
... Abstract: Halmahera is a K-shaped island located at the junction of several major arc-trench systems of the western Pacific-eastern Indonesia region. Western Halmahera is an active volcanic arc above a zone of intenseseismicitywhichcharacterizesthenorthMoluccaSea.EasternHalmaherahasa basement of dis ...
Origin of the concentrated deformation zone in the Japanese Islands... accumulation process of intraplate earthquakes
... above three conditions: (1) the velocity boundary condition model, to which we do not apply a constant stress boundary condition but a constant velocity boundary condition at the plate boundary; (2) the brittle-ductile interaction model where postseismic deformation occurs during an interseismic per ...
... above three conditions: (1) the velocity boundary condition model, to which we do not apply a constant stress boundary condition but a constant velocity boundary condition at the plate boundary; (2) the brittle-ductile interaction model where postseismic deformation occurs during an interseismic per ...
Metamorphic core complexes
... upper plate faults are truncated at their base by very low angle faults of large areal extent, which appear to be normal slip detachment faults. With continuous extension the blocks and faults rotate. The amount of rotation is described by the extension factor β. The extension factor is defined as q ...
... upper plate faults are truncated at their base by very low angle faults of large areal extent, which appear to be normal slip detachment faults. With continuous extension the blocks and faults rotate. The amount of rotation is described by the extension factor β. The extension factor is defined as q ...
Cuban Geology - Red Cubana de la Ciencia
... o n w a r ds, and from the Middle to Late Eocene in the Remedios Belt. They are not found in the Cayo Coco or northern Belts. This pattern of distribution of the exotic clastics is in agreement with a NE-ward movement of the allochthonous ophiolites and volcanic thrust-sheets. As the allochthon appr ...
... o n w a r ds, and from the Middle to Late Eocene in the Remedios Belt. They are not found in the Cayo Coco or northern Belts. This pattern of distribution of the exotic clastics is in agreement with a NE-ward movement of the allochthonous ophiolites and volcanic thrust-sheets. As the allochthon appr ...
The Contribution of Radiogenic Heat Production Studies to Hot Dry
... Ireland is located within stable lithosphere, unaffected by recent tectonism and volcanism. The upper crust under Ireland includes several thick Carboniferous sedimentary sequences where measured geothermal gradients are, for the most part, moderate (<25°C/km), though viable sources of geothermal en ...
... Ireland is located within stable lithosphere, unaffected by recent tectonism and volcanism. The upper crust under Ireland includes several thick Carboniferous sedimentary sequences where measured geothermal gradients are, for the most part, moderate (<25°C/km), though viable sources of geothermal en ...
27 Mineralogy and geochemistry of recent detrital sediments from
... Abstract Mineralogical and geochemical studies have been carried out on two alluvial profiles localised at the banks of an affluent of the Mayo Sina, South West of Chad. They were carried out in order to determine the composition of the source rock and the tectonic setting during the emplacement of ...
... Abstract Mineralogical and geochemical studies have been carried out on two alluvial profiles localised at the banks of an affluent of the Mayo Sina, South West of Chad. They were carried out in order to determine the composition of the source rock and the tectonic setting during the emplacement of ...
Folds, Faults and Mountain Belts (Con`t.)
... Affected by pressure (squeezing) and heat (magma). Occurs when converging plates squeeze rock caught between the plates. Crust generally thickens. Surface rocks get taken deep into the Earth. Rocks are subjected to high temperatures, lithostatic pressure and directed pressure. Rocks become foliated. ...
... Affected by pressure (squeezing) and heat (magma). Occurs when converging plates squeeze rock caught between the plates. Crust generally thickens. Surface rocks get taken deep into the Earth. Rocks are subjected to high temperatures, lithostatic pressure and directed pressure. Rocks become foliated. ...
pdf-file - Art Periods
... particularly important for understanding the mechanisms and consequences of plate coupling in subduction zones. The largest instrumentally recorded earthquake, the Mw = 9.5 1960 Valdivia earthquake, occurred along the south-central Chilean subduction zone and ruptured more than 1000 km length of the ...
... particularly important for understanding the mechanisms and consequences of plate coupling in subduction zones. The largest instrumentally recorded earthquake, the Mw = 9.5 1960 Valdivia earthquake, occurred along the south-central Chilean subduction zone and ruptured more than 1000 km length of the ...
Exam Block #3
... • Metamorphism progresses in increments from lowgrade to high-grade, but the rock remains solid! ...
... • Metamorphism progresses in increments from lowgrade to high-grade, but the rock remains solid! ...
Structures, Mountains and Continents
... Folds are bends; fractures are breaks and faults are breaks that have moved Folds, fractures and faults can occur at any spatial scale, from very small to very big The spatial orientation of planes such as rock layers is described using Strike and Dip Types of faults include normal (extensional), re ...
... Folds are bends; fractures are breaks and faults are breaks that have moved Folds, fractures and faults can occur at any spatial scale, from very small to very big The spatial orientation of planes such as rock layers is described using Strike and Dip Types of faults include normal (extensional), re ...
Chapter 13—Mesozoic Events
... tensional stress environment that caused rifting with associated normal faulting and basaltic volcanism. The rifts filled with alluvial and lacustrine sediments shed from adjacent fault-block mountains. The normal faults originated from gravity effects after crustal stretching and fracturing. Revers ...
... tensional stress environment that caused rifting with associated normal faulting and basaltic volcanism. The rifts filled with alluvial and lacustrine sediments shed from adjacent fault-block mountains. The normal faults originated from gravity effects after crustal stretching and fracturing. Revers ...
The Basin and Range Province: Origin and Tectonic Significance
... Blockfaults maycut through the full thickness of the crust as essentially planar features, or they mayactually reflect only the steep upperpart of very large-scale listric faults of great vertical extent, faults whoseradii of curvature in cross-section are muchlarger than those of moreobvious thin-s ...
... Blockfaults maycut through the full thickness of the crust as essentially planar features, or they mayactually reflect only the steep upperpart of very large-scale listric faults of great vertical extent, faults whoseradii of curvature in cross-section are muchlarger than those of moreobvious thin-s ...
the massabesic gneiss complex, new hampshire
... Rocks of the Avalon composite terrane are exposed in southeastern New England in Rhode Island and in large areas of southeastern Connecticut and eastern Massachusetts (fig. 1). Avalon is thought to represent a fragment of North Africa/Amazonia that accreted to North America and remained part of Nort ...
... Rocks of the Avalon composite terrane are exposed in southeastern New England in Rhode Island and in large areas of southeastern Connecticut and eastern Massachusetts (fig. 1). Avalon is thought to represent a fragment of North Africa/Amazonia that accreted to North America and remained part of Nort ...
The 10th Legion Thrust, Zeehan District
... regions (fig. 5), and the thrust event has involved at least two sedimentologically distinct Precambrian units, such as are recognised in the Sorell Peninsula (McClenaghan and Fmdlay, 1989). 4. The intemal structure of the Oonah Formation has not been resolved completely and nor has its sedimentolog ...
... regions (fig. 5), and the thrust event has involved at least two sedimentologically distinct Precambrian units, such as are recognised in the Sorell Peninsula (McClenaghan and Fmdlay, 1989). 4. The intemal structure of the Oonah Formation has not been resolved completely and nor has its sedimentolog ...
Chapter 4 Continental Margins and Ocean Basins
... activity and the processes of erosion and deposition. Near shore, the features of the ocean floor are similar to those of the adjacent continents because they share the same granitic basement. The transition to basalt marks the edge of the continent and divides ocean floors into two major provinces, ...
... activity and the processes of erosion and deposition. Near shore, the features of the ocean floor are similar to those of the adjacent continents because they share the same granitic basement. The transition to basalt marks the edge of the continent and divides ocean floors into two major provinces, ...
Geology of Greenland Survey Bulletin 177, 89-95
... itself nor in its underlying mantle. This is true for the regions of Early Archaean Amîtsoq gneiss within the Akulleq terrane immediately adjacent to the Akia terrane (e.g. McGregor et al., 1991) and is also well documented in other, younger parts of the Archaean block of southern West Greenland (se ...
... itself nor in its underlying mantle. This is true for the regions of Early Archaean Amîtsoq gneiss within the Akulleq terrane immediately adjacent to the Akia terrane (e.g. McGregor et al., 1991) and is also well documented in other, younger parts of the Archaean block of southern West Greenland (se ...
7. Early Evolution of the South Atlantic Ocean: Role of the Rifting
... which resulted in the formation of the continental margin. The sediments may be deposited in depressions created in an early stage of development, as is the case for the Bay of Biscay where there was a tensional episode during the Permian-Liassic at the site of the future break-up of continents befo ...
... which resulted in the formation of the continental margin. The sediments may be deposited in depressions created in an early stage of development, as is the case for the Bay of Biscay where there was a tensional episode during the Permian-Liassic at the site of the future break-up of continents befo ...
Great Lakes tectonic zone
The Great Lakes tectonic zone is bounded by South Dakota at its tip and heads northeast to south of Duluth, Minnesota, then heads east through northern Wisconsin, Marquette, Michigan, and then trends more northeasterly to skim the northern-most shores of lakes Michigan and Huron before ending in the Sudbury, Ontario, Canada, area.During the Late Archean Era the Algoman orogeny added landmass to the Superior province by volcanic activity and continental collision along a boundary that stretches from present-day South Dakota, U.S., into the Lake Huron region near Sudbury, Ontario, Canada.This crustal boundary is the Great Lakes tectonic zone. It is 1,400 km (870 mi) long, and separates the older Archean gneissic terrane to the south from younger Late Archean greenstone-granite terrane to the north.The zone is characterized by active compression during the Algoman orogeny (about 2,700 million years ago), a pulling-apart (extensional) tectonics (2,450 to 2,100 million years ago), a second compression during the Penokean orogeny (1,900 to 1,850 million years ago), a second extension during Middle Proterozoic time (1,600 million years ago) and minor reactivation during Phanerozoic time (the past 500 million years).Collision began along the Great Lakes tectonic zone (GLTZ) with the Algoman mountain-building event and continued for tens of millions of years. During the formation of the GLTZ, the gneissic Minnesota River Valley subprovince was thrust up onto the Superior province's edge as it consumed the Superior province's oceanic crust. Fragmentation of the Kenorland supercontinent began 2,450 million years ago and was completed by 2,100 million years ago. The Wyoming province is the continental landmass that is hypothesized to have rifted away from the southern Superior province portion of Kenorland, before moving rapidly west and docking with the Laurentia supercontinent 1,850 to 1,715 million years ago. Sedimentation from the GLTZ-rifting environment continued into the Penokean orogeny, which is the next major tectonic event in the Great Lakes region. Several earthquakes have been documented in Minnesota, Michigan's Upper Peninsula and Sudbury in the last 120 years along the GLTZ.