Deformation of Indian Ocean lithosphere
... deforming oceanic lithosphere. For example, Zatman et al. [2001, 2005] used simple analytical and numerical models of a thin viscous sheet to explore the relation between the pole of relative motion of component plates bounding a diffuse oceanic plate boundary and the orientation of the torque that ...
... deforming oceanic lithosphere. For example, Zatman et al. [2001, 2005] used simple analytical and numerical models of a thin viscous sheet to explore the relation between the pole of relative motion of component plates bounding a diffuse oceanic plate boundary and the orientation of the torque that ...
The Yellowstone `hot spot` track results from migrating basin range
... Snake River Plain-Yellowstone (ESRP-Y) zone were it not for the time-progressive chain of large rhyolitic caldera volcanoes there. The existence of such volcanic chains, and in particular their perceived fixity relative to the Hawaiian chain, was the cornerstone of the original plume hypothesis (Mor ...
... Snake River Plain-Yellowstone (ESRP-Y) zone were it not for the time-progressive chain of large rhyolitic caldera volcanoes there. The existence of such volcanic chains, and in particular their perceived fixity relative to the Hawaiian chain, was the cornerstone of the original plume hypothesis (Mor ...
the iberian variscan orogen
... blocks are nearby but separated by orogenic belts. It is thus clear that convergence caused the orogenic processes, and continental collision was the final result. We are talking about the convergence of three large tectonic plates: Laurentia (North America), Baltica (Scandinavia, northern belt of E ...
... blocks are nearby but separated by orogenic belts. It is thus clear that convergence caused the orogenic processes, and continental collision was the final result. We are talking about the convergence of three large tectonic plates: Laurentia (North America), Baltica (Scandinavia, northern belt of E ...
on circulation, phosphate-phosphorus content, and zooplankton
... the anticyclones helps to balance the outward diffusion, and the subarctic and subantarctic cyclones have substantial continental boundaries on one edge that help to confine some of the individuals. It is plausible to expect that these areas of semi-enclosed circulation and relatively narrow range o ...
... the anticyclones helps to balance the outward diffusion, and the subarctic and subantarctic cyclones have substantial continental boundaries on one edge that help to confine some of the individuals. It is plausible to expect that these areas of semi-enclosed circulation and relatively narrow range o ...
Remote sensing of water depths in shallow - Everglades-HUB
... architecture and parameters are two important steps to model and simulate water depths in shallow waters via the ANN model proposed in Fig. 3. Model inputs, reflectance from different spectral bands and in-situ measurements, should be processed before used in the modeling. Filtering, rectifying of th ...
... architecture and parameters are two important steps to model and simulate water depths in shallow waters via the ANN model proposed in Fig. 3. Model inputs, reflectance from different spectral bands and in-situ measurements, should be processed before used in the modeling. Filtering, rectifying of th ...
Ecosystem Functioning and Biodiversity in the Deep Sea (EuroDEEP)
... minerals, oil and gas resources, or the use of the deep benthic areas for waste and CO2 dumping, have been increasing steadily in the last decade. There is evidence of damage caused by some of these activities, resulting in significant biodiversity and habitat loss in ecosystems where recovery from ...
... minerals, oil and gas resources, or the use of the deep benthic areas for waste and CO2 dumping, have been increasing steadily in the last decade. There is evidence of damage caused by some of these activities, resulting in significant biodiversity and habitat loss in ecosystems where recovery from ...
Southern Ocean and South Pacific Region, Working Group 1
... amplify the other stressors such as rainfall or wave action. Areas of low primary production such as off the coast of Columbia and Ecuador and increased UV exposure in the Southern Ocean may also act as stressors for marine species in these areas. ...
... amplify the other stressors such as rainfall or wave action. Areas of low primary production such as off the coast of Columbia and Ecuador and increased UV exposure in the Southern Ocean may also act as stressors for marine species in these areas. ...
Thickness of the lithosphere beneath Turkey and
... an inclined 45 km thick high-velocity zone (slab) dipping to the north is used as the input model. The modeling has been performed for inclination angles between 0◦ and 50◦ with an increment of 10◦ . The velocity contrasts are from 8.0 to 7.5 km s−1 at the lower boundary of the slab and from 6.5 to ...
... an inclined 45 km thick high-velocity zone (slab) dipping to the north is used as the input model. The modeling has been performed for inclination angles between 0◦ and 50◦ with an increment of 10◦ . The velocity contrasts are from 8.0 to 7.5 km s−1 at the lower boundary of the slab and from 6.5 to ...
Basement structures from satellite-derived gravity field: South China
... oceanic areas the short-wavelength component of the observed signal is generally well correlated with the bathymetry, a fact which was used by Sandwell and Smith [2001] and Smith and Sandwell [1997] to formulate the global bathymetric model derived from the integration of the global gravity anomaly ...
... oceanic areas the short-wavelength component of the observed signal is generally well correlated with the bathymetry, a fact which was used by Sandwell and Smith [2001] and Smith and Sandwell [1997] to formulate the global bathymetric model derived from the integration of the global gravity anomaly ...
- ResearchOnline@JCU
... Bulk-rock major and trace element geochemistry of a range of eclogite, garnet blueschist and garnet amphibolite rocks from northern New Caledonia has been determined in order to geochemically characterise subducted oceanic crust. The rocks experienced peak metamorphic conditions of 1.9 GPa and 600 j ...
... Bulk-rock major and trace element geochemistry of a range of eclogite, garnet blueschist and garnet amphibolite rocks from northern New Caledonia has been determined in order to geochemically characterise subducted oceanic crust. The rocks experienced peak metamorphic conditions of 1.9 GPa and 600 j ...
Global Tectonics - dynamicearth.de
... (Section 2.13). Heat flow in the past must have been considerably greater than at present due to the exponential decay rates of these isotopes (Fig. 11.1). For an Earth model with a K/U ratio derived from measurements of crustal rocks, the heat flow in the crust at 4.0 Ga would have been three times ...
... (Section 2.13). Heat flow in the past must have been considerably greater than at present due to the exponential decay rates of these isotopes (Fig. 11.1). For an Earth model with a K/U ratio derived from measurements of crustal rocks, the heat flow in the crust at 4.0 Ga would have been three times ...
Simulation of the mantle and crustal helium isotope
... following years in the Gulf of Lion was satisfactorily captured as well. However, some aspects of the model still need to be improved: in the eastern basin, tritium/helium-3 simulations have highlighted the too-weak formation of Adriatic Deep Water (AdDW), followed by a weak contribution to the East ...
... following years in the Gulf of Lion was satisfactorily captured as well. However, some aspects of the model still need to be improved: in the eastern basin, tritium/helium-3 simulations have highlighted the too-weak formation of Adriatic Deep Water (AdDW), followed by a weak contribution to the East ...
The South-east African margin and its marine basins and ridge
... Basin is almost 155 Myr old (Jokat et al, in press). Towards the west, the margin is younger than previously expected. Clear magnetic anomalies off the Explora Escarpment are dated to 140 Ma, i.e. about 40 Myr younger than the oldest onshore magmatism in Antarctica (Jokat et al, in press). In SE Afr ...
... Basin is almost 155 Myr old (Jokat et al, in press). Towards the west, the margin is younger than previously expected. Clear magnetic anomalies off the Explora Escarpment are dated to 140 Ma, i.e. about 40 Myr younger than the oldest onshore magmatism in Antarctica (Jokat et al, in press). In SE Afr ...
Scenarios and Drivers for Sustainable Growth from the Oceans, Seas
... Exploitation of the sea-floor is governed by the United Nations Convention on the Law of the sea (UNCLOS). It was adopted in 1982 and ratified in 1994 and sets out the legal regime for the Economic Exclusive Zones (EEZs) of countries and the internationals waters beyond the EEZs. EEZs constitute the ...
... Exploitation of the sea-floor is governed by the United Nations Convention on the Law of the sea (UNCLOS). It was adopted in 1982 and ratified in 1994 and sets out the legal regime for the Economic Exclusive Zones (EEZs) of countries and the internationals waters beyond the EEZs. EEZs constitute the ...
Thermal Structure due to Solid-State Flow in the Mantle
... with petrologic constraints. One caveat is that trajectories of melt migration beneath an arc might not be vertical. Porous flow might lead to melt migration vectors that ascend diagonally toward the wedge corner either due to pressure gradients in the mantle flow [Spiegelman and McKenzie, 1987; Phi ...
... with petrologic constraints. One caveat is that trajectories of melt migration beneath an arc might not be vertical. Porous flow might lead to melt migration vectors that ascend diagonally toward the wedge corner either due to pressure gradients in the mantle flow [Spiegelman and McKenzie, 1987; Phi ...
eastern european alpine system and the carpathian
... The first geologic evidence to suggest convergence of fragments is present in latest Jurassic rocks. Within what is now the Vardar zone (Fig. 1) separating the Apulian and Rhodopian fragments, is Late Jurassic flysch locally containing volcanic detritus that was deformed and intruded by a small gran ...
... The first geologic evidence to suggest convergence of fragments is present in latest Jurassic rocks. Within what is now the Vardar zone (Fig. 1) separating the Apulian and Rhodopian fragments, is Late Jurassic flysch locally containing volcanic detritus that was deformed and intruded by a small gran ...
Dohan, K., and N. Maximenko, 2010: Monitoring ocean currents with
... Figure 1 shows a schematic of this surface current hierarchy. Although local currents have been observed for centuries for purposes such as navigation and fishing, the advent of satellite remote sensing has provided us with regular and global measurements of the complex ocean surface motions. Weste ...
... Figure 1 shows a schematic of this surface current hierarchy. Although local currents have been observed for centuries for purposes such as navigation and fishing, the advent of satellite remote sensing has provided us with regular and global measurements of the complex ocean surface motions. Weste ...
Newly identi¢ed segments of the Paci¢c^Australia plate boundary
... The North Fiji transform zone, a 1500 km long and 200 km wide transform segment of the Pacific^Australia plate boundary, is one of the major transform fault systems of the Earth. New data collected during the ALAUFI cruise (March 2000) on board the R/V L'Atalante make it possible to define more accu ...
... The North Fiji transform zone, a 1500 km long and 200 km wide transform segment of the Pacific^Australia plate boundary, is one of the major transform fault systems of the Earth. New data collected during the ALAUFI cruise (March 2000) on board the R/V L'Atalante make it possible to define more accu ...
Key Issues on the Commercial Development of Deep Seabed
... Session. This means that the Authority now will treat issues related to development as a priority. The discussion about enactment of the Regulations on the Commercial Development of Polymetallic Nodules by the Authority seemed related to the seabed mining activities of various private enterprises. S ...
... Session. This means that the Authority now will treat issues related to development as a priority. The discussion about enactment of the Regulations on the Commercial Development of Polymetallic Nodules by the Authority seemed related to the seabed mining activities of various private enterprises. S ...
Age Determination of Marine Sediments in the Western North Pacific
... in the ages estimated by these two methods were also obvious at the depths of 66.3 and 139 cm. Anomalies in Asp age corresponding to the depths of 66.3 cm and 139 cm were 33,000 during 60,000–80,000 yrBP and 46,600 yr during 140,000–190,000 yrBP, respectively (Fig. 4). It is believed that such anoma ...
... in the ages estimated by these two methods were also obvious at the depths of 66.3 and 139 cm. Anomalies in Asp age corresponding to the depths of 66.3 cm and 139 cm were 33,000 during 60,000–80,000 yrBP and 46,600 yr during 140,000–190,000 yrBP, respectively (Fig. 4). It is believed that such anoma ...
Climate variability and ocean production in the Leeuwin Current
... high resolution, data-assimilating numerical simulation of the ocean system (Schiller et al. 2008). The LC at 22°S is a broad, shallow surface current in the upper 150m, carrying waters of the tropical origin southward (Figure 2). The LC builds up its strength along the shelf break off Shark Bay and ...
... high resolution, data-assimilating numerical simulation of the ocean system (Schiller et al. 2008). The LC at 22°S is a broad, shallow surface current in the upper 150m, carrying waters of the tropical origin southward (Figure 2). The LC builds up its strength along the shelf break off Shark Bay and ...
Buildup of a dynamically supported orogenic plateau: Numerical
... High Zagros, Alborz, and Kopet Dagh. Much of the plateau interior is seismically inactive or affected by long-term recurrence strike-slip faults [Talebian and Jackson, 2002; Meyer et al., 2006; Allen et al., 2011]. The scarcity of active thrusts and low internal strain suggest that the interior of t ...
... High Zagros, Alborz, and Kopet Dagh. Much of the plateau interior is seismically inactive or affected by long-term recurrence strike-slip faults [Talebian and Jackson, 2002; Meyer et al., 2006; Allen et al., 2011]. The scarcity of active thrusts and low internal strain suggest that the interior of t ...
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... volcanic and plutonic complexes, and (3) the formation of accretionary mélange complexes during the subduction of oceanic crust. Rock assemblages characteristic of oceanic crust and island arc suites may also be formed during Hadean-style convection, making the recognition of accretionary mélange co ...
... volcanic and plutonic complexes, and (3) the formation of accretionary mélange complexes during the subduction of oceanic crust. Rock assemblages characteristic of oceanic crust and island arc suites may also be formed during Hadean-style convection, making the recognition of accretionary mélange co ...
Contraction or expansion of the Moon`s crust during magma ocean
... Previous workers [10] investigated the constraints a given bulk composition exerts on the solidifying phase assemblages. They found that in the absence of tightly constraining phase equilibrium data, there is significant leeway—without violating bounds on the bulk magma ocean composition—in both the ...
... Previous workers [10] investigated the constraints a given bulk composition exerts on the solidifying phase assemblages. They found that in the absence of tightly constraining phase equilibrium data, there is significant leeway—without violating bounds on the bulk magma ocean composition—in both the ...
Arthur Holmes` paper of 1929 on convection currents within the
... episodic eruptions of plateau basalts and orogenies. Subsequently (Joly, 1924, 1925) argued that the Earth could not be cooling as Lord Kelvin had supposed in the nineteenth century. On the contrary, it was constantly generating subterranean heat, which was discharged from time to time. The heat gen ...
... episodic eruptions of plateau basalts and orogenies. Subsequently (Joly, 1924, 1925) argued that the Earth could not be cooling as Lord Kelvin had supposed in the nineteenth century. On the contrary, it was constantly generating subterranean heat, which was discharged from time to time. The heat gen ...
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.