Thermo-rheological, shear heating model for leucogranite
... radioactive elements does not yield sufficiently high temperatures to cause anatexis anywhere in the crust or growth of garnet in the now exposed part of the crust; (2) a 35-km drop-off length for internal heat production can yield sufficient temperature for garnet growth at the current erosion leve ...
... radioactive elements does not yield sufficiently high temperatures to cause anatexis anywhere in the crust or growth of garnet in the now exposed part of the crust; (2) a 35-km drop-off length for internal heat production can yield sufficient temperature for garnet growth at the current erosion leve ...
A review of community ecology of mesophotic coral reef ecosystems
... representative subset of well-studied MCE locations are summarized in the remainder of this section. Western Atlantic In general, MCEs have been found on deeper fore-reef slopes adjacent to shallow-water coral reefs, deep-water rhodolith beds, and on isolated offshore banks on the continental shelf. ...
... representative subset of well-studied MCE locations are summarized in the remainder of this section. Western Atlantic In general, MCEs have been found on deeper fore-reef slopes adjacent to shallow-water coral reefs, deep-water rhodolith beds, and on isolated offshore banks on the continental shelf. ...
Processes of Magma Evolution and Magmatic Suites
... regions where lithospheric extension has created intra-plate rifts. The African Rift Valley is a prime example. There are a number of more exotic primary magmas, usually highly alkaline primary magmas, which are very small in volume but have a paramount petrological and geodynamic importance. These ...
... regions where lithospheric extension has created intra-plate rifts. The African Rift Valley is a prime example. There are a number of more exotic primary magmas, usually highly alkaline primary magmas, which are very small in volume but have a paramount petrological and geodynamic importance. These ...
subduction zones
... to migrate toward the ocean or “roll back.” Old, dense lithosphere readily sinks, while young, buoyant lithosphere resists subduction. Subduction of old lithosphere results in relatively steep subduction zones, whereas subduction of young lithosphere is characterized by shallower dips [Jarrard, 1986 ...
... to migrate toward the ocean or “roll back.” Old, dense lithosphere readily sinks, while young, buoyant lithosphere resists subduction. Subduction of old lithosphere results in relatively steep subduction zones, whereas subduction of young lithosphere is characterized by shallower dips [Jarrard, 1986 ...
Structure and evolution of the northern Oman margin: gravity and
... The obduction process in Oman during Late Cretaceous time, and continental-to-oceanic subduction along the ZagrosMakran region during the Tertiary are consequences of the Arabian-Eurasian collision, resulting in construction of complex structures composed of the Oman ophiolite belt, the Zagros conti ...
... The obduction process in Oman during Late Cretaceous time, and continental-to-oceanic subduction along the ZagrosMakran region during the Tertiary are consequences of the Arabian-Eurasian collision, resulting in construction of complex structures composed of the Oman ophiolite belt, the Zagros conti ...
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... to migrate toward the ocean or “roll back.” Old, dense lithosphere readily sinks, while young, buoyant lithosphere resists subduction. Subduction of old lithosphere results in relatively steep subduction zones, whereas subduction of young lithosphere is characterized by shallower dips [Jarrard, 1986 ...
... to migrate toward the ocean or “roll back.” Old, dense lithosphere readily sinks, while young, buoyant lithosphere resists subduction. Subduction of old lithosphere results in relatively steep subduction zones, whereas subduction of young lithosphere is characterized by shallower dips [Jarrard, 1986 ...
Autonomous adaptive environmental assessment and feature tracking via autonomous underwater vehicles
... that information to alter its course and more fully capture the feature’s properties in its data. A. Science/Oceanography At-sea data collection is typically a very expensive and planning-intensive exercise for oceanographers, often limiting ...
... that information to alter its course and more fully capture the feature’s properties in its data. A. Science/Oceanography At-sea data collection is typically a very expensive and planning-intensive exercise for oceanographers, often limiting ...
Whole-mantle convection and the transition
... composed of MORB source materials, because it has so few radioactive heat sources; the remaining heat sources are thus thought to be hidden at greater depths in isolated reservoirs unsampled by mid-ocean ridges, but possibly sampled by plumes. In total, these and other observations suggest that the ...
... composed of MORB source materials, because it has so few radioactive heat sources; the remaining heat sources are thus thought to be hidden at greater depths in isolated reservoirs unsampled by mid-ocean ridges, but possibly sampled by plumes. In total, these and other observations suggest that the ...
Reflecting on the Legal-Technical Interface of Article 76 of the
... Underlying the aforementioned point is a key question the answer to which is far from having been given conclusively: To what extent does the legal nature of Article 76 bear on the scientific-technical implementation of this provision? Or to put it in another way, to what degree – if any – is the i ...
... Underlying the aforementioned point is a key question the answer to which is far from having been given conclusively: To what extent does the legal nature of Article 76 bear on the scientific-technical implementation of this provision? Or to put it in another way, to what degree – if any – is the i ...
7. Geologic Framework of the Falkland Plateau
... banks and submarine ridges that extends 2000 km from Tierra del Fuego to South Georgia (Figs. 1 and 2). The ridge is generally viewed as the northern east-westtrending limb of the loop-shaped Scotia Arc, which provides physiographic continuity between the southern tip of South America and the Antarc ...
... banks and submarine ridges that extends 2000 km from Tierra del Fuego to South Georgia (Figs. 1 and 2). The ridge is generally viewed as the northern east-westtrending limb of the loop-shaped Scotia Arc, which provides physiographic continuity between the southern tip of South America and the Antarc ...
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... northern margin of the Gulf of Mexico. Here we report and discuss shear-wave splitting observations for the crust and upper mantle beneath the northern margin of the Gulf of Mexico. The region that spans the northern Gulf of Mexico margin underwent two complete cycles of continental rifting (540 and ...
... northern margin of the Gulf of Mexico. Here we report and discuss shear-wave splitting observations for the crust and upper mantle beneath the northern margin of the Gulf of Mexico. The region that spans the northern Gulf of Mexico margin underwent two complete cycles of continental rifting (540 and ...
Glossary Accommodation zone—Accommodation zone is the zone
... place, developing an organized spreading ridge system. Yet another example of the disorganized spreading, this time from the magma-poor setting, is at least 6 million year-long exhumation of the continental lithospheric mantle, responsible for a 70-73 km wide corridor of the so-called proto-oceanic ...
... place, developing an organized spreading ridge system. Yet another example of the disorganized spreading, this time from the magma-poor setting, is at least 6 million year-long exhumation of the continental lithospheric mantle, responsible for a 70-73 km wide corridor of the so-called proto-oceanic ...
mymaster - DUO
... of the waves inside the Earth is mostly related to the temperature and compositional variations that occur. In lesser extent, wave propagation velocity depends on a small-scale property of the medium which is the orientation of crystals in it. ...
... of the waves inside the Earth is mostly related to the temperature and compositional variations that occur. In lesser extent, wave propagation velocity depends on a small-scale property of the medium which is the orientation of crystals in it. ...
Convergent plate margin dynamics
... Convergent plate margins occur when two adjoining tectonic plates come together to form either a subduction zone, where at least one of the converging plates is oceanic and plunges beneath the other into the mantle, or a collision zone, where two continents or a continent and a magmatic arc collide. ...
... Convergent plate margins occur when two adjoining tectonic plates come together to form either a subduction zone, where at least one of the converging plates is oceanic and plunges beneath the other into the mantle, or a collision zone, where two continents or a continent and a magmatic arc collide. ...
ferrari answers
... 2) How do we tell the difference between the subduction of a spreading ridge and a slab window? Ridge are passive features formed at surface where two plate tear apart and the asthenosphere flow up to form new oceanic crust. When a ridge intersects a subduction zone a slab window is created instead, ...
... 2) How do we tell the difference between the subduction of a spreading ridge and a slab window? Ridge are passive features formed at surface where two plate tear apart and the asthenosphere flow up to form new oceanic crust. When a ridge intersects a subduction zone a slab window is created instead, ...
CV - Jill Mcdermott
... Ballanetine C.J. (2015) Determining the mean residence age of Precambrian fluid systems, 25th Annual V.M. Goldschmidt Conference, Prague, Czech Republic. Link to abst. Glein C., Zhu A., Sutcliffe C., McDermott J.M. and Sherwood Lollar B. (2015) The potential for abiotic organic synthesis in an ancie ...
... Ballanetine C.J. (2015) Determining the mean residence age of Precambrian fluid systems, 25th Annual V.M. Goldschmidt Conference, Prague, Czech Republic. Link to abst. Glein C., Zhu A., Sutcliffe C., McDermott J.M. and Sherwood Lollar B. (2015) The potential for abiotic organic synthesis in an ancie ...
Untitled - International Seabed Authority
... intensively exploited offshore for several decades. Offshore production of tin in Southeast Asia is considerable. Gold has been mined offshore intermittently. Diamonds are currently extracted from the seabed offshore Namibia and South Africa (Corbett, ...
... intensively exploited offshore for several decades. Offshore production of tin in Southeast Asia is considerable. Gold has been mined offshore intermittently. Diamonds are currently extracted from the seabed offshore Namibia and South Africa (Corbett, ...
Organic carbon and humic acids in sediments of the
... The distribution of sediments away from the coast suggests that the inner shelf is characterized by a more rapid rate of sedimentation than the outer shelf. The upper continental slope also bas high rates of sedimentation, though not as high as in the coastal areas. The estimated rate of sedimentati ...
... The distribution of sediments away from the coast suggests that the inner shelf is characterized by a more rapid rate of sedimentation than the outer shelf. The upper continental slope also bas high rates of sedimentation, though not as high as in the coastal areas. The estimated rate of sedimentati ...
Variations in amount and direction of seafloor spreading along
... during the Cenozoic. Seafloor spreading occurred along three ridge systems: the Reykjanes Ridge south of Iceland, the Mohns Ridge north of the Jan Mayen Fracture Zone (JMFZ), and the Aegir and Kolbeinsey Ridges between Iceland and the JMFZ. At the same time, compressional structures developed along ...
... during the Cenozoic. Seafloor spreading occurred along three ridge systems: the Reykjanes Ridge south of Iceland, the Mohns Ridge north of the Jan Mayen Fracture Zone (JMFZ), and the Aegir and Kolbeinsey Ridges between Iceland and the JMFZ. At the same time, compressional structures developed along ...
the seamounts of the gorringe bank
... metres in height and can consist of very different physical, geological and chemical properties. Therefore, seamounts can only exist where there are sea beds more than one kilometre deep, or, which is one and the same thing, over 60%–62% of the land surface1. There are also thousands of smaller elev ...
... metres in height and can consist of very different physical, geological and chemical properties. Therefore, seamounts can only exist where there are sea beds more than one kilometre deep, or, which is one and the same thing, over 60%–62% of the land surface1. There are also thousands of smaller elev ...
The Behavior of the Lithosphere on Seismic to Geologic Timescales
... The Earth’s lithosphere responds to the forces imposed on it during, for example, subduction and orogeny and continental breakup and rifting by continuously deforming. The deformation is manifest in geological and geophysical observations such as the structural styles in orogens, the stratigraphic “ ...
... The Earth’s lithosphere responds to the forces imposed on it during, for example, subduction and orogeny and continental breakup and rifting by continuously deforming. The deformation is manifest in geological and geophysical observations such as the structural styles in orogens, the stratigraphic “ ...
Geology, 39
... Greenland eclogites supports the observation by Shirey and Richardson (2011) that mantle eclogite materials older than 3.0 Ga appear absent from the cratonic record. They suggest that the appearance of cratonic eclogites in most cratons after 3.0 Ga marks the onset of the Wilson Cycle of plate tecto ...
... Greenland eclogites supports the observation by Shirey and Richardson (2011) that mantle eclogite materials older than 3.0 Ga appear absent from the cratonic record. They suggest that the appearance of cratonic eclogites in most cratons after 3.0 Ga marks the onset of the Wilson Cycle of plate tecto ...
research agenda 2025
... circulation. Of special significance are changes in the Atlantic Meridional Overturning Circulation (MOC), the “lower limb” involving formation and circulation of deep waters. In the North Atlantic, the “upper limb” of the MOC transports vast amounts of heat towards the high northern latitudes and is ...
... circulation. Of special significance are changes in the Atlantic Meridional Overturning Circulation (MOC), the “lower limb” involving formation and circulation of deep waters. In the North Atlantic, the “upper limb” of the MOC transports vast amounts of heat towards the high northern latitudes and is ...
Capitanio et al. - Wiley Online Library
... What drives the deformation in the interiors of continents remain to date mostly unexplained [Molnar, 1988]. Continental tectonics during collision must ultimately relate to the subduction zones dynamics, where the fundamental tectonic forces originate. However, the observed complex patterns and evo ...
... What drives the deformation in the interiors of continents remain to date mostly unexplained [Molnar, 1988]. Continental tectonics during collision must ultimately relate to the subduction zones dynamics, where the fundamental tectonic forces originate. However, the observed complex patterns and evo ...
Partial delamination of continental mantle lithosphere, uplift
... Received 21 January 2000; revised 30 May 2000; accepted 16 June 2000 ...
... Received 21 January 2000; revised 30 May 2000; accepted 16 June 2000 ...
Abyssal plain
An abyssal plain is an underwater plain on the deep ocean floor, usually found at depths between 3000 and 6000 m. Lying generally between the foot of a continental rise and a mid-ocean ridge, abyssal plains cover more than 50% of the Earth’s surface. They are among the flattest, smoothest and least explored regions on Earth. Abyssal plains are key geologic elements of oceanic basins (the other elements being an elevated mid-ocean ridge and flanking abyssal hills). In addition to these elements, active oceanic basins (those that are associated with a moving plate tectonic boundary) also typically include an oceanic trench and a subduction zone.Abyssal plains were not recognized as distinct physiographic features of the sea floor until the late 1940s and, until very recently, none had been studied on a systematic basis. They are poorly preserved in the sedimentary record, because they tend to be consumed by the subduction process. The creation of the abyssal plain is the end result of spreading of the seafloor (plate tectonics) and melting of the lower oceanic crust. Magma rises from above the asthenosphere (a layer of the upper mantle) and as this basaltic material reaches the surface at mid-ocean ridges it forms new oceanic crust. This is constantly pulled sideways by spreading of the seafloor. Abyssal plains result from the blanketing of an originally uneven surface of oceanic crust by fine-grained sediments, mainly clay and silt. Much of this sediment is deposited by turbidity currents that have been channelled from the continental margins along submarine canyons down into deeper water. The remainder of the sediment is composed chiefly of pelagic sediments. Metallic nodules are common in some areas of the plains, with varying concentrations of metals, including manganese, iron, nickel, cobalt, and copper. These nodules may provide a significant resource for future mining ventures.Owing in part to their vast size, abyssal plains are currently believed to be a major reservoir of biodiversity. The abyss also exerts significant influence upon ocean carbon cycling, dissolution of calcium carbonate, and atmospheric CO2 concentrations over timescales of 100–1000 years. The structure and function of abyssal ecosystems are strongly influenced by the rate of flux of food to the seafloor and the composition of the material that settles. Factors such as climate change, fishing practices, and ocean fertilization are expected to have a substantial effect on patterns of primary production in the euphotic zone. This will undoubtedly impact the flux of organic material to the abyss in a similar manner and thus have a profound effect on the structure, function and diversity of abyssal ecosystems.