Styles of post-subduction collisional orogeny: Influence of
... Therefore, we performed 2D numerical experiments of oceanic-continental subduction followed by continental collision for varying continental lower crustal strength, convergence velocity and radiogenic heating rate. Oceanic subduction produces thinning and upwarping of the overriding lithospheric wed ...
... Therefore, we performed 2D numerical experiments of oceanic-continental subduction followed by continental collision for varying continental lower crustal strength, convergence velocity and radiogenic heating rate. Oceanic subduction produces thinning and upwarping of the overriding lithospheric wed ...
Twin Hotspot Tracks and Ridge Jumps
... et al ; Barckhausen et al ) It has been demonstrated that the products of the hotspot volcanism covered a complex pattern of oceanic crust formed at three subsequently active symmetric spreading systems of different orientation The identified extinct spreading systems represent precur ...
... et al ; Barckhausen et al ) It has been demonstrated that the products of the hotspot volcanism covered a complex pattern of oceanic crust formed at three subsequently active symmetric spreading systems of different orientation The identified extinct spreading systems represent precur ...
Controls on Sr/Ca in benthic foraminifera and implications for
... We analysed Sr/Ca in three calcitic (Cibicidoides wuellerstorfi, Cibicidoides mundulus, and Uvigerina spp.) and one aragonitic (Hoeglundina elegans) benthic foraminiferal species from 156 coretop samples from the global ocean (Tables S1e4). These core-tops are verified to be late Holocene (0e5 ka) in ...
... We analysed Sr/Ca in three calcitic (Cibicidoides wuellerstorfi, Cibicidoides mundulus, and Uvigerina spp.) and one aragonitic (Hoeglundina elegans) benthic foraminiferal species from 156 coretop samples from the global ocean (Tables S1e4). These core-tops are verified to be late Holocene (0e5 ka) in ...
An experimental study on major element release from the sediments
... in the sediments can also make some contribution to Ca and Mg release, although it is difficult to quantitatively calculate their influence. The more detailed characterization of residual sediments after the dissolution experiment may be necessary to reveal the possible roles of carbonate and silica ...
... in the sediments can also make some contribution to Ca and Mg release, although it is difficult to quantitatively calculate their influence. The more detailed characterization of residual sediments after the dissolution experiment may be necessary to reveal the possible roles of carbonate and silica ...
Marine Geology: Exploring the New Frontiers of the Ocean (The
... axis, completing a single rotation every 14 hours, thus maintaining high temperatures throughout the planet. Present-day plate tectonic processes could not have operated under such hot conditions, which produced more vertical bubbling than horizontal sliding. Therefore, modern-style plate tectonic p ...
... axis, completing a single rotation every 14 hours, thus maintaining high temperatures throughout the planet. Present-day plate tectonic processes could not have operated under such hot conditions, which produced more vertical bubbling than horizontal sliding. Therefore, modern-style plate tectonic p ...
Origin of the concentrated deformation zone in the Japanese Islands... accumulation process of intraplate earthquakes
... coast (NKTZ: Niigata-Kobe Tectonic Zone) has been detected by dense GPS arrays (GEONET by Geographical Survey Institute), as shown in Fig. 1 (Sagiya et al., 2000). The observed horizontal displacement rates in NKTZ were fitted, quantitatively, by 3 kinematic models named as the detachment model (Hir ...
... coast (NKTZ: Niigata-Kobe Tectonic Zone) has been detected by dense GPS arrays (GEONET by Geographical Survey Institute), as shown in Fig. 1 (Sagiya et al., 2000). The observed horizontal displacement rates in NKTZ were fitted, quantitatively, by 3 kinematic models named as the detachment model (Hir ...
Evolution of the East African and related orogens, and the assembly
... the Arabian–Nubian Shield. The difference in lithology and metamorphic grade between the two belts has been attributed to the difference in the level of exposure, with the Mozambican rocks interpreted as lower crustal equivalents of the juvenile rocks in the Arabian–Nubian Shield. Recent geochronolo ...
... the Arabian–Nubian Shield. The difference in lithology and metamorphic grade between the two belts has been attributed to the difference in the level of exposure, with the Mozambican rocks interpreted as lower crustal equivalents of the juvenile rocks in the Arabian–Nubian Shield. Recent geochronolo ...
Incipient shortening of a passive margin: the mechanical roles of
... In this paper we investigate post-break-up incipient shortening and thickening of passive margins, under the action of horizontal compression. One source of compression is ridge push. It results from the topographic effects of cooling and contraction of the oceanic lithosphere, away from an active s ...
... In this paper we investigate post-break-up incipient shortening and thickening of passive margins, under the action of horizontal compression. One source of compression is ridge push. It results from the topographic effects of cooling and contraction of the oceanic lithosphere, away from an active s ...
The Model of Oceanic Crust Expansion
... that the oceanic crust expansion accounts for in the discharge of matters, the length of the expansion belt stretching for 15,000 km, the thickness of the oceanic crust being 10 km, the width of the oceanic crust expansion belt being 66 km, the cycle to form a group of oceanic crusts is approximatel ...
... that the oceanic crust expansion accounts for in the discharge of matters, the length of the expansion belt stretching for 15,000 km, the thickness of the oceanic crust being 10 km, the width of the oceanic crust expansion belt being 66 km, the cycle to form a group of oceanic crusts is approximatel ...
Key - Scioly.org
... A: Pacific Plate B: African Plate C: Nazca Plate D: North America Plate E: Eurasian Plate F: South American Plate 9. Sediments derived from pre-existing rock are called ___________ sediments. Answer: lithogenous 10. Particles from space are referred to as __________ sediment. Answer: cosmogenous 11. ...
... A: Pacific Plate B: African Plate C: Nazca Plate D: North America Plate E: Eurasian Plate F: South American Plate 9. Sediments derived from pre-existing rock are called ___________ sediments. Answer: lithogenous 10. Particles from space are referred to as __________ sediment. Answer: cosmogenous 11. ...
Epipelagic fish
... In the deep ocean, the waters extend far below the epipelagic zone, and support very different types of pelagic fishes adapted to living in these deeper zones.[2] In deep water, marine snow is a continuous shower of mostly organic detritus falling from the upper layers of the water column. Its orig ...
... In the deep ocean, the waters extend far below the epipelagic zone, and support very different types of pelagic fishes adapted to living in these deeper zones.[2] In deep water, marine snow is a continuous shower of mostly organic detritus falling from the upper layers of the water column. Its orig ...
LOW RES
... melt somewhere in the subduction zone system. Early thermal models of subduction zones assumed a priori that arc magmas were derived from direct melts of the subducting slab and these models incorporated high rates of shear heating along the slab-mantle interface in order to supply the required heat ...
... melt somewhere in the subduction zone system. Early thermal models of subduction zones assumed a priori that arc magmas were derived from direct melts of the subducting slab and these models incorporated high rates of shear heating along the slab-mantle interface in order to supply the required heat ...
Why is subduction on the Earth one-sided?
... Subduction of the lithosphere at convergent-plate boundaries takes place asymmetrically— the subducted slab sinks downward, while the overriding plate moves horizontally (one-sided subduction). In contrast, global mantle convection models generally predict downwelling of both plates at convergent ma ...
... Subduction of the lithosphere at convergent-plate boundaries takes place asymmetrically— the subducted slab sinks downward, while the overriding plate moves horizontally (one-sided subduction). In contrast, global mantle convection models generally predict downwelling of both plates at convergent ma ...
1 The tectonic agenda
... • The deforming plate boundaries are very narrow in comparison to the lateral dimensions of the individual plates. Plate tectonicscan only provide a useful description if the number of plates remains small; if large numbers of plates are needed to describe the behaviour of the lithosphere, then the ...
... • The deforming plate boundaries are very narrow in comparison to the lateral dimensions of the individual plates. Plate tectonicscan only provide a useful description if the number of plates remains small; if large numbers of plates are needed to describe the behaviour of the lithosphere, then the ...
On the origin of the asthenosphere
... the inferred shallow lithosphere–asthenosphere boundary (LAB) with a large and sharp velocity reduction in the old oceanic mantle by partial melting, a high end of the geotherm and some mechanisms of melt accumulation are required. Purely thermal sub-solidus model of the asthenosphere is inconsisten ...
... the inferred shallow lithosphere–asthenosphere boundary (LAB) with a large and sharp velocity reduction in the old oceanic mantle by partial melting, a high end of the geotherm and some mechanisms of melt accumulation are required. Purely thermal sub-solidus model of the asthenosphere is inconsisten ...
Atmosphere-Ocean Coupling and Surface Circulation of the Ocean
... southwest Africa and the desert areas of North Africa, the Red Sea, and the Persian Gulf constitute mid-latitude zones of descending dry air, which increases in temperature through conduction and high pressure (adiabatic compression) as it approaches Earth’s surface. Clear air over Antarctica is due ...
... southwest Africa and the desert areas of North Africa, the Red Sea, and the Persian Gulf constitute mid-latitude zones of descending dry air, which increases in temperature through conduction and high pressure (adiabatic compression) as it approaches Earth’s surface. Clear air over Antarctica is due ...
FREE Sample Here
... of movement of that rock can be calculated. If a number of these samples are taken from various distances from the hotspot, the calculation can be quite accurate. [p. 61] 26. Briefly explain why there is so much oil in the Persian Gulf region. Answer: During the Mesozoic, the Persian Gulf was a broa ...
... of movement of that rock can be calculated. If a number of these samples are taken from various distances from the hotspot, the calculation can be quite accurate. [p. 61] 26. Briefly explain why there is so much oil in the Persian Gulf region. Answer: During the Mesozoic, the Persian Gulf was a broa ...
Constraints on flux rates and mantle dynamics beneath island arcs
... localize the sheeted downwellings of upper-mantle convection3. The surface expressions of subduction are the curved chains of active volcanoes that form island arcs, and the magmatic flux in these volcanoes is an important component of new crustal additions. Conversely, the subduction of oceanic cru ...
... localize the sheeted downwellings of upper-mantle convection3. The surface expressions of subduction are the curved chains of active volcanoes that form island arcs, and the magmatic flux in these volcanoes is an important component of new crustal additions. Conversely, the subduction of oceanic cru ...
DS3F White Paper - Deep Sea Frontier
... The marine environment is particularly important to the European Union because 50% of its territory lies offshore, 25 member states have coastlines, nearly 50% of its citizens live within 50 km of the coast and 4.8 million EU inhabitants are directly employed in maritime activities1. The deep sea is ...
... The marine environment is particularly important to the European Union because 50% of its territory lies offshore, 25 member states have coastlines, nearly 50% of its citizens live within 50 km of the coast and 4.8 million EU inhabitants are directly employed in maritime activities1. The deep sea is ...
Shervais, J.W., Significance of Subduction
... The transition from Hadean-style convective overturn, driven by heating from below, and Phanerozoic-style plate tectonics, driven by the sinking of cool lithospheric slabs, was a major turning point in the thermal evolution of the Earth. Prior to this transition the formation of stable, long-lived c ...
... The transition from Hadean-style convective overturn, driven by heating from below, and Phanerozoic-style plate tectonics, driven by the sinking of cool lithospheric slabs, was a major turning point in the thermal evolution of the Earth. Prior to this transition the formation of stable, long-lived c ...
Structure of the Earth`s Crust in Fennoscandia as Revealed from
... Sveka'81, POLAR and FENNOLORA covering the area from the South to the North are chosen to be reviewed. The interpretation of data in those cases has been also rather similar. The locations of the profile lines are seen in Fig. 1 and the velocity models along the profiles in Fig. 3. The BABEL A profi ...
... Sveka'81, POLAR and FENNOLORA covering the area from the South to the North are chosen to be reviewed. The interpretation of data in those cases has been also rather similar. The locations of the profile lines are seen in Fig. 1 and the velocity models along the profiles in Fig. 3. The BABEL A profi ...
A three-component plan of drilling and monitoring around a
... temperature and pressure. In the cases of subduction zones around the southern Kanto region in Japan (Figure 1), North Island of New Zealand, and Mexico, in contrast, slow slip events occur at relatively shallow depths, at the same level as the asperity, raising the possibility of different conditio ...
... temperature and pressure. In the cases of subduction zones around the southern Kanto region in Japan (Figure 1), North Island of New Zealand, and Mexico, in contrast, slow slip events occur at relatively shallow depths, at the same level as the asperity, raising the possibility of different conditio ...
7 Volcano-tectonic Interactions in Kyushu and Implications for Future
... The configuration of the subducting slab, as well as the laterally varying buoyancy properties of the subducting plate exert a major influence on the nature of volcanism and tectonic deformation in Kyushu. Given that these properties will tend to evolve spatially with time, we show a series of model ...
... The configuration of the subducting slab, as well as the laterally varying buoyancy properties of the subducting plate exert a major influence on the nature of volcanism and tectonic deformation in Kyushu. Given that these properties will tend to evolve spatially with time, we show a series of model ...
Plate Tectonics: A Paradigm Under Threat
... oceanic crust under the influence of gravitational and rotational forces. Interest was revived in the early 1950s with the rise of the new science of paleomagnetism, which seemed to provide strong support for continental drift. In the early 1960s, new data from ocean exploration led to the idea of s ...
... oceanic crust under the influence of gravitational and rotational forces. Interest was revived in the early 1950s with the rise of the new science of paleomagnetism, which seemed to provide strong support for continental drift. In the early 1960s, new data from ocean exploration led to the idea of s ...
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.