plate tectonic framework and gps - Perso-sdt
... The results achieved so far can be considered as a first important step towards a better understanding of the geologic evolution, geophysical structure and present-day dynamics of the Alpine-Mediterranean region (Kahle and Mueller, 1998). However, most of the deformation processes are not yet fully ...
... The results achieved so far can be considered as a first important step towards a better understanding of the geologic evolution, geophysical structure and present-day dynamics of the Alpine-Mediterranean region (Kahle and Mueller, 1998). However, most of the deformation processes are not yet fully ...
Subduction of the Rivera plate beneath the Jalisco block as imaged
... of the Rivera plate under the Jalisco block (JB). The geometry of the subducting slab is inferred by the anomalous conductor on the top of the profile in the central part of the JB. High conductivity zones (<50 ohm-m) at depths shallower than 10 km are associated to dewatering of the oceanic crust b ...
... of the Rivera plate under the Jalisco block (JB). The geometry of the subducting slab is inferred by the anomalous conductor on the top of the profile in the central part of the JB. High conductivity zones (<50 ohm-m) at depths shallower than 10 km are associated to dewatering of the oceanic crust b ...
The Aegean: plate tectonic evolution in Mediterranean
... Ocean basin began to close to the north. Some parts of the basin were subducted beneath Eurasia and others were stacked at the massif, such as in the Vardar zone (Higgins & Higgins, 1996). In the following the isotopic zones of the Aegean were transported to the north, as a result of the expansion o ...
... Ocean basin began to close to the north. Some parts of the basin were subducted beneath Eurasia and others were stacked at the massif, such as in the Vardar zone (Higgins & Higgins, 1996). In the following the isotopic zones of the Aegean were transported to the north, as a result of the expansion o ...
Impact of lower plate structure on upper plate
... highlights those portions of the seafloor shaped by active tectonic, depositional and/or erosional processes. The greatest slope gradients are located in the frontal 30 km of the forearc, at the toe of the accretionary wedge. This suggests that long-term deformation rates are highest here and that p ...
... highlights those portions of the seafloor shaped by active tectonic, depositional and/or erosional processes. The greatest slope gradients are located in the frontal 30 km of the forearc, at the toe of the accretionary wedge. This suggests that long-term deformation rates are highest here and that p ...
Science Article PDF - Geological Society of America
... et al., 1986). There is no arc-related magmatism in the South Shetland Islands much younger than 20 Ma, which Barker ...
... et al., 1986). There is no arc-related magmatism in the South Shetland Islands much younger than 20 Ma, which Barker ...
Nakajima_etal_GRL200.. - Research School of Earth Sciences
... obliquely subducting plates, the Philippine Sea and Pacific plates [Seno et al., 1996] (Figure 1). An area of slab-slab contact, where the bottom of the Philippine Sea slab is in contact with the upper surface of the Pacific slab, is defined beneath Kanto on the basis of high-resolution seismic velo ...
... obliquely subducting plates, the Philippine Sea and Pacific plates [Seno et al., 1996] (Figure 1). An area of slab-slab contact, where the bottom of the Philippine Sea slab is in contact with the upper surface of the Pacific slab, is defined beneath Kanto on the basis of high-resolution seismic velo ...
Convergent Plate Boundaries - North Coast Distance Education
... two oceanic plates, (b) convergence of an oceanic and a continental plate, and (c) collision of two continental plates. The first two involve subduction of oceanic lithosphere into the mantle. Plate temperatures, convergence rates, and convergence directions play important roles in determining the f ...
... two oceanic plates, (b) convergence of an oceanic and a continental plate, and (c) collision of two continental plates. The first two involve subduction of oceanic lithosphere into the mantle. Plate temperatures, convergence rates, and convergence directions play important roles in determining the f ...
Did Paleo-Tethyan anoxia kill arc magma fertility for
... restriction to Phanerozoic arc rocks reflects the delay of deep ocean oxidation, and therefore oxidative seafloor alteration and subduction zone metasomatism, until after the Neoproterozoic oxygenation event (Evans and Tomkins, 2011; Richards and Mumin, 2013). However, extensive periods of deep ocea ...
... restriction to Phanerozoic arc rocks reflects the delay of deep ocean oxidation, and therefore oxidative seafloor alteration and subduction zone metasomatism, until after the Neoproterozoic oxygenation event (Evans and Tomkins, 2011; Richards and Mumin, 2013). However, extensive periods of deep ocea ...
Evidence for Early Cretaceous oceanic crust trapped in the
... Ar/39 Ar dates. These new 40 Ar/39 Ar ages on two gabbro sites dredged in the Huatung Basin indicate the existence of Early Cretaceous oceanic crust east of Taiwan. The di¡erent amphibole age spectra are partially discordant, probably as a result of some hydrothermal alteration on the oceanic £oor. ...
... Ar/39 Ar dates. These new 40 Ar/39 Ar ages on two gabbro sites dredged in the Huatung Basin indicate the existence of Early Cretaceous oceanic crust east of Taiwan. The di¡erent amphibole age spectra are partially discordant, probably as a result of some hydrothermal alteration on the oceanic £oor. ...
FREE Sample Here
... (a) Use a red line to show the trace of the Red Sea rift/ridge axis. Use a purple line to show the trace of the Dead Sea transform fault. (b) The narrow ocean bordering the southeast edge of the Arabian Peninsula is the Gulf of Aden. Use red and purple lines to trace the ridge segments and transform ...
... (a) Use a red line to show the trace of the Red Sea rift/ridge axis. Use a purple line to show the trace of the Dead Sea transform fault. (b) The narrow ocean bordering the southeast edge of the Arabian Peninsula is the Gulf of Aden. Use red and purple lines to trace the ridge segments and transform ...
Thermal structure of the Costa Rica – Nicaragua subduction zone
... earthquakes define a Wadati-Benioff zone that marks the subducting Cocos plate and extends to 250 km depth beneath Nicaragua (Protti et al., 1995; Husen et al., 2003). A 1500 km-long volcanic arc extends from southern Mexico to central Costa Rica, but there is no Holocene volcanism in southern Costa ...
... earthquakes define a Wadati-Benioff zone that marks the subducting Cocos plate and extends to 250 km depth beneath Nicaragua (Protti et al., 1995; Husen et al., 2003). A 1500 km-long volcanic arc extends from southern Mexico to central Costa Rica, but there is no Holocene volcanism in southern Costa ...
Origin and time evolution of subduction polarity reversal from plate
... orogeny and questions the hypothesis that northern Taiwan can be considered an older, more mature equivalent of southern Taiwan. INTRODUCTION Subduction zones are major drivers of plate motions (e.g., Conrad and Lithgow-Bertelloni, 2002; Stadler et al., 2010) and govern much of Earth’s topography; t ...
... orogeny and questions the hypothesis that northern Taiwan can be considered an older, more mature equivalent of southern Taiwan. INTRODUCTION Subduction zones are major drivers of plate motions (e.g., Conrad and Lithgow-Bertelloni, 2002; Stadler et al., 2010) and govern much of Earth’s topography; t ...
the North American Cordillera: from Baja to British Columbia Growth
... 1985). Kimbrough et al. (2001) proposed that the development of erosional topography in the Late Cretaceous was related to the emplacement of voluminous magmatic bodies. Pre-exhumation reconstruction of the eastern zone at ~100 Ma indicates crustal thickness of the order of ~55 km (Schmidt 2000). Th ...
... 1985). Kimbrough et al. (2001) proposed that the development of erosional topography in the Late Cretaceous was related to the emplacement of voluminous magmatic bodies. Pre-exhumation reconstruction of the eastern zone at ~100 Ma indicates crustal thickness of the order of ~55 km (Schmidt 2000). Th ...
Aseismic zone and earthquake segmentation associated with a
... at subduction zones. However, the role of subducted features in the generation of megathrust earthquakes has been difficult to discern because traditional imaging techniques are limited to the upper 12 km of the Earth’s crust12 , whereas these ruptures initiate at depths of 20–40 km (ref. 13). Here ...
... at subduction zones. However, the role of subducted features in the generation of megathrust earthquakes has been difficult to discern because traditional imaging techniques are limited to the upper 12 km of the Earth’s crust12 , whereas these ruptures initiate at depths of 20–40 km (ref. 13). Here ...
A dynamic model of hot fingers in the mantle wedge in
... Japan arc, and he suggested that the mantle wedge may have been replenished several times by the addition of fertile mantle materials (Kushiro, 1990). Shibata and Nakamura (1997) suggested that the volume of subducted material (oceanic sediments and altered MORB) added to the mantle wedge decreases ...
... Japan arc, and he suggested that the mantle wedge may have been replenished several times by the addition of fertile mantle materials (Kushiro, 1990). Shibata and Nakamura (1997) suggested that the volume of subducted material (oceanic sediments and altered MORB) added to the mantle wedge decreases ...
Oceanic Lithosphere
... transforms into a form in which the atoms are packed more closely, known as spinel, with a consequent increase in density of about 10%. There is further phase change at about 670km where the spinel structure transforms into an even-higher pressure form known as perovskite with another density increa ...
... transforms into a form in which the atoms are packed more closely, known as spinel, with a consequent increase in density of about 10%. There is further phase change at about 670km where the spinel structure transforms into an even-higher pressure form known as perovskite with another density increa ...
Seafloor spreading around Australia R. Dietmar Müller, Carmen
... Fig. 6. C31 Late Cretaceous (Maastrichtian) 67.7 Ma. The ridge in the Tasman Sea propagated N-ward. S-ward the ridge propagated between the Campbell Plateau and Antarctica. The ridge jumped N-ward between Broken Ridge and Kerguelen Plateau. (i) C25 late Paleocene 55.9 Ma The spreading direction bet ...
... Fig. 6. C31 Late Cretaceous (Maastrichtian) 67.7 Ma. The ridge in the Tasman Sea propagated N-ward. S-ward the ridge propagated between the Campbell Plateau and Antarctica. The ridge jumped N-ward between Broken Ridge and Kerguelen Plateau. (i) C25 late Paleocene 55.9 Ma The spreading direction bet ...
Sum4_Flatslabs
... Next we moved into discussions of why the slab is flat. Jerome mentioned that early work by Jarrard (his 1986 paper is referenced in van Hunen, 2002) showed that there is no correlation between age of the subducting slab and slab dip. This may be the reason why people moved to talking about oceanic ...
... Next we moved into discussions of why the slab is flat. Jerome mentioned that early work by Jarrard (his 1986 paper is referenced in van Hunen, 2002) showed that there is no correlation between age of the subducting slab and slab dip. This may be the reason why people moved to talking about oceanic ...
Metamorphic processes in the subducting slab and overlying mantle
... models can be tested by petrologic and geochemical constraints from subduction-related metamorphic rocks (e.g. Bebout, 1995, 2007; Breeding and Ague, 2002). The models can be refined by better constraints on model inputs, such as the degree of hydration of oceanic lithosphere and by inclusion of (de ...
... models can be tested by petrologic and geochemical constraints from subduction-related metamorphic rocks (e.g. Bebout, 1995, 2007; Breeding and Ague, 2002). The models can be refined by better constraints on model inputs, such as the degree of hydration of oceanic lithosphere and by inclusion of (de ...
2003108 - Geological Society of America
... (as inferred from earthquakes by Pardo and Suárez, 1995) are included for reference. Approximate locations of Deep Sea Drilling Project legs 66 (L66), 67 (L67), and 84 (L84) are also indicated. Our geochemical database for the MVB (411 individual samples) concerns a wider area to the East and to the ...
... (as inferred from earthquakes by Pardo and Suárez, 1995) are included for reference. Approximate locations of Deep Sea Drilling Project legs 66 (L66), 67 (L67), and 84 (L84) are also indicated. Our geochemical database for the MVB (411 individual samples) concerns a wider area to the East and to the ...
hanson_summer_2011_poster - Sound Ideas
... The Cascade Range is a classic example of a continental magmatic arc, a belt of igneous activity resulting from subduction of the oceanic Juan de Fuca plate beneath the western margin of the North American plate. The Cascade arc, which started forming about 38 million years ago (Ma), is unique in th ...
... The Cascade Range is a classic example of a continental magmatic arc, a belt of igneous activity resulting from subduction of the oceanic Juan de Fuca plate beneath the western margin of the North American plate. The Cascade arc, which started forming about 38 million years ago (Ma), is unique in th ...
Subduction of the oceanic Hikurangi Plateau and its impact on the
... petrogenesis and eruptive behaviour of arc volcanoes, fluid-flow in their associated hydrothermal systems, and element transfer to the oceans. The Hikurangi Plateau is believed to have formed as part of Ontong Java Nui during the ‘greater Ontong Java event’ B120 Myr ago, one of the world’s most extr ...
... petrogenesis and eruptive behaviour of arc volcanoes, fluid-flow in their associated hydrothermal systems, and element transfer to the oceans. The Hikurangi Plateau is believed to have formed as part of Ontong Java Nui during the ‘greater Ontong Java event’ B120 Myr ago, one of the world’s most extr ...
Powerpoint template for scientific poster
... The mantle plume theory, or Yellowstone Hotspot theory, suggests that the source of the eruptions are from a mantle plume, possibly the hotspot that now rests underneath Yellowstone National Park. This hotspot did indeed move through the general area across the Snake River plain around the time the ...
... The mantle plume theory, or Yellowstone Hotspot theory, suggests that the source of the eruptions are from a mantle plume, possibly the hotspot that now rests underneath Yellowstone National Park. This hotspot did indeed move through the general area across the Snake River plain around the time the ...
Research Focus: Crust formation in the western United
... was added to the southern margin of the Archean Wyoming craton. In the prevailing arc-accretion model (Condie, 1982; Karlstrom and Bowring, 1988; 1993), most of this material is considered to be mantle-derived juvenile crust, and therefore represents newly formed crust (at 1.8–1.6 Ga). The interesti ...
... was added to the southern margin of the Archean Wyoming craton. In the prevailing arc-accretion model (Condie, 1982; Karlstrom and Bowring, 1988; 1993), most of this material is considered to be mantle-derived juvenile crust, and therefore represents newly formed crust (at 1.8–1.6 Ga). The interesti ...
Izu-Bonin-Mariana Arc
The Izu-Bonin-Mariana (IBM) arc system is an outstanding example of a plate tectonic convergent boundary. IBM extends over 2800 km south from Tokyo, Japan, to beyond Guam, and includes the Izu Islands, Bonin Islands, and Mariana Islands; much more of the IBM arc system is submerged below sealevel. The IBM arc system lies along the eastern margin of the Philippine Sea Plate in the Western Pacific Ocean. It is most famous for being the site of the deepest gash in Earth's solid surface, the Challenger Deep in the Mariana Trench. The IBM arc system formed as a result of subduction of the western Pacific plate. The IBM arc system now subducts mid-Jurassic to Early Cretaceous lithosphere, with younger lithosphere in the north and older lithosphere in the south, including the oldest (~170 million years old, or Ma) oceanic crust. Subduction rates vary from ~2 cm (1 inch) per year in the south to 6 cm (~2.5 inches) in the north. The volcanic islands that comprise these island arcs are thought to have been formed from the release of volatiles (steam from trapped water, and other gases) being released from the subducted plate, as it reached sufficient depth for the temperature to cause release of these materials. The associated trenches are formed as the oldest (most western) part of the Pacific plate crust increases in density with age, and because of this process finally reaches its lowest point just as it subducts under the crust to the west of it.The IBM arc system is an excellent example of an intra-oceanic convergent margin (IOCM). IOCMs are built on oceanic crust and contrast fundamentally with island arc built on continental crust, such as Japan or the Andes. Because IOCM crust is thinner, denser, and more refractory than that beneath Andean-type margins, study of IOCM melts and fluids allows more confident assessment of mantle-to-crust fluxes and processes than is possible for Andean-type convergent margins. Because IOCMs are far removed from continents they are not affected by the large volume of alluvial and glacial sediments. The consequent thin sedimentary cover makes it much easier to study arc infrastructure and determine the mass and composition of subducted sediments. Active hydrothermal systems found on the submarine parts of IOCMs give us a chance to study how many of earth's important ore deposits formed.