Mechanism of Formation of Active Margins.
... becn Înjected from a large depth. most Iikel y from the core-mantle boundary. Low-velocity and low-denSÎl y ma ntle mate r ial is segregaled from the hOI upper mantle benealh ac tive margins. It forms a la yer severa l tens of kilo mete rs thic k bcneath the lithosphere. Oceanic lithos phe re is den ...
... becn Înjected from a large depth. most Iikel y from the core-mantle boundary. Low-velocity and low-denSÎl y ma ntle mate r ial is segregaled from the hOI upper mantle benealh ac tive margins. It forms a la yer severa l tens of kilo mete rs thic k bcneath the lithosphere. Oceanic lithos phe re is den ...
CRCT Question of the Day 1-5-11
... B. Near a rainy coastal area close to the equator C. At the mouth of a large river. D. In cold, deep water, near the ocean bottom Standard & Element – S6E3.c ...
... B. Near a rainy coastal area close to the equator C. At the mouth of a large river. D. In cold, deep water, near the ocean bottom Standard & Element – S6E3.c ...
Whole-mantle convection with tectonic plates preserves long
... of particles in an equivalent volume in each layer plotted against depth (km). Due to the decreasing volume represented at individual layers in the spherical model, the population densities in the mapped views appear to lessen towards the lower mantle. Here, we plot the percentage of particles withi ...
... of particles in an equivalent volume in each layer plotted against depth (km). Due to the decreasing volume represented at individual layers in the spherical model, the population densities in the mapped views appear to lessen towards the lower mantle. Here, we plot the percentage of particles withi ...
Consulta: subjectFacets:"Crustal structure" Registros recuperados
... were collected in 2000 during the ZaïAngo cruise. These data help constrain the deep structure of the continental margin, the geometry of the pre-salt sediment layers and the geometry of the Aptian salt layer. Dating the deposition of the salt relative to the chronology of the margin formation is an ...
... were collected in 2000 during the ZaïAngo cruise. These data help constrain the deep structure of the continental margin, the geometry of the pre-salt sediment layers and the geometry of the Aptian salt layer. Dating the deposition of the salt relative to the chronology of the margin formation is an ...
Plate-Tectonics A review
... This is how Wegener thought the continents moved over the last 200 million years:- ...
... This is how Wegener thought the continents moved over the last 200 million years:- ...
Whole-mantle convection with tectonic plates preserves
... of particles in an equivalent volume in each layer plotted against depth (km). Due to the decreasing volume represented at individual layers in the spherical model, the population densities in the mapped views appear to lessen towards the lower mantle. Here, we plot the percentage of particles withi ...
... of particles in an equivalent volume in each layer plotted against depth (km). Due to the decreasing volume represented at individual layers in the spherical model, the population densities in the mapped views appear to lessen towards the lower mantle. Here, we plot the percentage of particles withi ...
exhanges.naobook
... development of numerous extensions from paleoclimate proxies, and Cook (2002) critically reviews these attempts. He also presents a new winter NAO index reconstruction back to AD 1400. Another reason for invigorated interest in the NAO is that the richly complex and differential responses of the sur ...
... development of numerous extensions from paleoclimate proxies, and Cook (2002) critically reviews these attempts. He also presents a new winter NAO index reconstruction back to AD 1400. Another reason for invigorated interest in the NAO is that the richly complex and differential responses of the sur ...
Ocean Climate Indicators Status Report: 2015
... relatively low throughout our time series, with significant increases in 2011-12. Euphausiid biomass (as measured by acoustics) appears to peak in late summer (July) in most years. Adult euphausiids, which are larger and higher in lipid content than their younger counterparts, dominate the zooplankt ...
... relatively low throughout our time series, with significant increases in 2011-12. Euphausiid biomass (as measured by acoustics) appears to peak in late summer (July) in most years. Adult euphausiids, which are larger and higher in lipid content than their younger counterparts, dominate the zooplankt ...
On the origin of El Chichón volcano and subduction of
... oceanic crust represent another important fluid reservoir, and their metamorphic changes lead to fluid release into the mantle wedge, which enhance the serpentinization process. The serpentinization process not only produce magnetite and increase significantly the remanent magnetization (with an order ...
... oceanic crust represent another important fluid reservoir, and their metamorphic changes lead to fluid release into the mantle wedge, which enhance the serpentinization process. The serpentinization process not only produce magnetite and increase significantly the remanent magnetization (with an order ...
Imaging the lithosphere‐asthenosphere boundary
... thickness of subducting lithosphere from land stations at the Japan, Aleutian, and North American ocean‐continent plate boundaries [Kumar and Kawakatsu, 2011]. Finally, a significant (4.7–14.3%) seismic discontinuity at constant depth beneath the seafloor (63–80 km depending on the study) has also b ...
... thickness of subducting lithosphere from land stations at the Japan, Aleutian, and North American ocean‐continent plate boundaries [Kumar and Kawakatsu, 2011]. Finally, a significant (4.7–14.3%) seismic discontinuity at constant depth beneath the seafloor (63–80 km depending on the study) has also b ...
The climatology, meteorology, and boundary layer structure of
... strong events, which occur mostly in winter. The particular numbers are chosen such that the total ...
... strong events, which occur mostly in winter. The particular numbers are chosen such that the total ...
The monsoon circulation of the Indian Ocean
... in Oceanography, 1994, Vol.33, number 3) provided a comprehensive analysis of the entire monsoon cycle using a 212-layer model. They forced the model with annual wind-stress and heat-flux climatologies, compared their solution to the existing observational data base, and reviewed prior modelling wor ...
... in Oceanography, 1994, Vol.33, number 3) provided a comprehensive analysis of the entire monsoon cycle using a 212-layer model. They forced the model with annual wind-stress and heat-flux climatologies, compared their solution to the existing observational data base, and reviewed prior modelling wor ...
inferences on potential seamount locations from
... The results were also restricted by both methods in the scope of the area around each peak was tested for seamount characteristics. The kernel used by method 1 equates to an area of approximately 342 km2 at the equator. It was hoped that a kernel of this size would allow the detection of large seamo ...
... The results were also restricted by both methods in the scope of the area around each peak was tested for seamount characteristics. The kernel used by method 1 equates to an area of approximately 342 km2 at the equator. It was hoped that a kernel of this size would allow the detection of large seamo ...
Supplemental Readings on Earthquakes
... Closely examine Figures 7.11 and 7.12 on p. 198 of your textbook. These diagrams very nicely illustrate what happens at a sea-floor spreading ridge. The two oceanic plates are spreading apart with new plate material forming in the middle. Here is how the new plate material forms: In the asthenospher ...
... Closely examine Figures 7.11 and 7.12 on p. 198 of your textbook. These diagrams very nicely illustrate what happens at a sea-floor spreading ridge. The two oceanic plates are spreading apart with new plate material forming in the middle. Here is how the new plate material forms: In the asthenospher ...
Supplemental Readings on Earthquakes
... Closely examine Figures 7.11 and 7.12 on p. 198 of your textbook. These diagrams very nicely illustrate what happens at a sea-floor spreading ridge. The two oceanic plates are spreading apart with new plate material forming in the middle. Here is how the new plate material forms: In the asthenospher ...
... Closely examine Figures 7.11 and 7.12 on p. 198 of your textbook. These diagrams very nicely illustrate what happens at a sea-floor spreading ridge. The two oceanic plates are spreading apart with new plate material forming in the middle. Here is how the new plate material forms: In the asthenospher ...
Large Igneous Provinces, Delamination, and Fertile Mantle
... ridge material in LIP magmas. Some igneous provinces are built on top of rafted pieces of microcontinents or abandoned island arcs, but is there any mechanism for putting large chunks of continental material into the source regions of LIPs? Lower crustal delamination is such a mechanism, although it ...
... ridge material in LIP magmas. Some igneous provinces are built on top of rafted pieces of microcontinents or abandoned island arcs, but is there any mechanism for putting large chunks of continental material into the source regions of LIPs? Lower crustal delamination is such a mechanism, although it ...
Resource Supply Overrides Temperature as a Controlling Factor of
... The universal temperature dependence of metabolic rates has been used to predict how ocean biology will respond to ocean warming. Determining the temperature sensitivity of phytoplankton metabolism and growth is of special importance because this group of organisms is responsible for nearly half of ...
... The universal temperature dependence of metabolic rates has been used to predict how ocean biology will respond to ocean warming. Determining the temperature sensitivity of phytoplankton metabolism and growth is of special importance because this group of organisms is responsible for nearly half of ...
Asthenospheric flow and origin of volcanism in the Baikal Rift area
... flow in the mantle beneath the Baikal Rift Zone and argue that it is sub-horizontal asthenospheric flow that may give rise to volcanism in this and perhaps many other rift areas. The Baikal Rift Zone is located at the boundary of the stable Siberian Platform and deforming Baikal-Sayan fold belt (Fig ...
... flow in the mantle beneath the Baikal Rift Zone and argue that it is sub-horizontal asthenospheric flow that may give rise to volcanism in this and perhaps many other rift areas. The Baikal Rift Zone is located at the boundary of the stable Siberian Platform and deforming Baikal-Sayan fold belt (Fig ...
Clay Mineral Distribution in Surface Sediments of the
... water column becomes more important. Near the continental slopes much of the clay material can be derived from turbidity currents and local, dense thermohaline underflows (Kuhn and Weber, 1993). With increasing distance from source areas thermohaline current systems determine the clay composition wi ...
... water column becomes more important. Near the continental slopes much of the clay material can be derived from turbidity currents and local, dense thermohaline underflows (Kuhn and Weber, 1993). With increasing distance from source areas thermohaline current systems determine the clay composition wi ...
New insights into the subducting oceanic crust in the Middle
... The seismic data used to constrain the top of the oceanic slab entering the trench at approximately 18"30'N, 104"30W consist of two profiles perpendicular to the MAT (Dañobeitia et al., 1997). Fig. 4A and B displays the MCS profiles 106" and 104" acquired along track 1 and track 2, respectively (Fig ...
... The seismic data used to constrain the top of the oceanic slab entering the trench at approximately 18"30'N, 104"30W consist of two profiles perpendicular to the MAT (Dañobeitia et al., 1997). Fig. 4A and B displays the MCS profiles 106" and 104" acquired along track 1 and track 2, respectively (Fig ...
Plate Tectonics: GL209 Prof. John Tarney Lecture 5: Subduction
... SUBDUCTION ZONES and ISLAND ARCS Subduction Zones are where cool lithospheric plates sink back into the mantle. It takes about 50 my for the ocean lithosphere that formed in the hot (>1000°C) environment at mid-ocean ridges to cool to an equilibrium state and sink to its maximum depth below sea-leve ...
... SUBDUCTION ZONES and ISLAND ARCS Subduction Zones are where cool lithospheric plates sink back into the mantle. It takes about 50 my for the ocean lithosphere that formed in the hot (>1000°C) environment at mid-ocean ridges to cool to an equilibrium state and sink to its maximum depth below sea-leve ...
the iberian variscan orogen
... The West Asturian-Leonese Zone, and the part of the Central Iberian Zone adjacent to it in Galicia, were key areas in the definition of the different types of granitoids and their interpretation (Capdevila, 1969; Capdevila et al.,1973). The oldest granitoids (Figure 10) are typically biotitic, frequ ...
... The West Asturian-Leonese Zone, and the part of the Central Iberian Zone adjacent to it in Galicia, were key areas in the definition of the different types of granitoids and their interpretation (Capdevila, 1969; Capdevila et al.,1973). The oldest granitoids (Figure 10) are typically biotitic, frequ ...
PHYTOPLANKTON, ZOOPLANKTON, MICRONEKTON, AND
... coastal ecosystems generally, and specifically, to provide integrated assessments of the effect of environmental variability and climate change on coastal marine ecosystems within the NEP. The data sets assembled and collected within the GLOBEC NEP program--including historical data, and newly colle ...
... coastal ecosystems generally, and specifically, to provide integrated assessments of the effect of environmental variability and climate change on coastal marine ecosystems within the NEP. The data sets assembled and collected within the GLOBEC NEP program--including historical data, and newly colle ...
GEOPHYSICAL CHARACTERISTICS OF THE NINETYEAST RIDGE
... The convergence tectonics of the Ninetyeast ridge (NER), upon the Andaman island arc trench system is examined through an analysis of ETOPO2 bathymetry, satellite-derived free air gravity and seismic data. Oblique subduction and the buoyancy forces arising from subduction of the NER render the subdu ...
... The convergence tectonics of the Ninetyeast ridge (NER), upon the Andaman island arc trench system is examined through an analysis of ETOPO2 bathymetry, satellite-derived free air gravity and seismic data. Oblique subduction and the buoyancy forces arising from subduction of the NER render the subdu ...
Ocean
An ocean (from Ancient Greek Ὠκεανός, transc. Okeanós, the sea of classical antiquity) is a body of saline water that composes much of a planet's hydrosphere. On Earth, an ocean is one of the major conventional divisions of the World Ocean, which covers almost 71% of its surface. These are, in descending order by area, the Pacific, Atlantic, Indian, Southern, and Arctic Oceans. The word sea is often used interchangeably with ""ocean"" in American English but, strictly speaking, a sea is a body of saline water (generally a division of the world ocean) partly or fully enclosed by land.Saline water covers approximately 72% of the planet's surface (~3.6×108 km2) and is customarily divided into several principal oceans and smaller seas, with the ocean covering approximately 71% of Earth's surface. The ocean contains 97% of Earth's water, and oceanographers have stated that only 5% of the World Ocean has been explored. The total volume is approximately 1.35 billion cubic kilometers (320 million cu mi) with an average depth of nearly 3,700 meters (12,100 ft).As it is the principal component of Earth's hydrosphere, the world ocean is integral to all known life, forms part of the carbon cycle, and influences climate and weather patterns. It is the habitat of 230,000 known species, although much of the oceans depths remain unexplored, and over two million marine species are estimated to exist. The origin of Earth's oceans remains unknown; oceans are thought to have formed in the Hadean period and may have been the impetus for the emergence of life.Extraterrestrial oceans may be composed of water or other elements and compounds. The only confirmed large stable bodies of extraterrestrial surface liquids are the lakes of Titan, although there is evidence for the existence of oceans elsewhere in the Solar System. Early in their geologic histories, Mars and Venus are theorized to have had large water oceans. The Mars ocean hypothesis suggests that nearly a third of the surface of Mars was once covered by water, and a runaway greenhouse effect may have boiled away the global ocean of Venus. Compounds such as salts and ammonia dissolved in water lower its freezing point, so that water might exist in large quantities in extraterrestrial environments as brine or convecting ice. Unconfirmed oceans are speculated beneath the surface of many dwarf planets and natural satellites; notably, the ocean of Europa is estimated to have over twice the water volume of Earth. The Solar System's giant planets are also thought to have liquid atmospheric layers of yet to be confirmed compositions. Oceans may also exist on exoplanets and exomoons, including surface oceans of liquid water within a circumstellar habitable zone. Ocean planets are a hypothetical type of planet with a surface completely covered with liquid.