Neo-Tethys geodynamics and mantle convection: from - HAL-Insu
... mantle. We suggest that alternating extension and compression in Africa could be explained by switching convection regimes. The extensional situation would correspond to steady-state whole-mantle convection, Africa being carried northward by a large-scale conveyor belt, while compression and obducti ...
... mantle. We suggest that alternating extension and compression in Africa could be explained by switching convection regimes. The extensional situation would correspond to steady-state whole-mantle convection, Africa being carried northward by a large-scale conveyor belt, while compression and obducti ...
Genesis of the Neogene to Quaternary volcanism in the Carpathian
... during the early Miocene (Royden, 1993). Retreat of the subduction zone beneath the Carpathians is considered to have been the main driving force for the lateral movement of the North Pannonian block toward the northeast. Behind the subduction zone, backarc extension occurred in the whole Pannonian ...
... during the early Miocene (Royden, 1993). Retreat of the subduction zone beneath the Carpathians is considered to have been the main driving force for the lateral movement of the North Pannonian block toward the northeast. Behind the subduction zone, backarc extension occurred in the whole Pannonian ...
- Arizona State University
... rocks, there is potential for shear wave ray paths to have travel times of several seconds within the deep sedimentary basins crossed by the RISTRA network, which is an appreciable fraction of the total travel time through the crust. Because of the strong impedance contrast between the rocks in the ...
... rocks, there is potential for shear wave ray paths to have travel times of several seconds within the deep sedimentary basins crossed by the RISTRA network, which is an appreciable fraction of the total travel time through the crust. Because of the strong impedance contrast between the rocks in the ...
R7: Taylor-Evolution of Continental Crust
... diamonds can be up to three billion years old and thus demonstrate the antiquity of the deep continental roots. It is curious to reßect that less than 40 years ago, there was no evidence that the rocks lining ocean basins diÝered in any fundamental way from those found on land. The oceans were simpl ...
... diamonds can be up to three billion years old and thus demonstrate the antiquity of the deep continental roots. It is curious to reßect that less than 40 years ago, there was no evidence that the rocks lining ocean basins diÝered in any fundamental way from those found on land. The oceans were simpl ...
The evolution of continental crust
... diamonds can be up to three billion years old and thus demonstrate the antiquity of the deep continental roots. It is curious to reßect that less than 40 years ago, there was no evidence that the rocks lining ocean basins diÝered in any fundamental way from those found on land. The oceans were simpl ...
... diamonds can be up to three billion years old and thus demonstrate the antiquity of the deep continental roots. It is curious to reßect that less than 40 years ago, there was no evidence that the rocks lining ocean basins diÝered in any fundamental way from those found on land. The oceans were simpl ...
Earth,Tests,Ch12
... Answer: a) base of lithosphere or top of asthenosphere (top of low velocity zone) b) inner core c) lower mantle (mesosphere) d) asthenosphere Diff: 1 ...
... Answer: a) base of lithosphere or top of asthenosphere (top of low velocity zone) b) inner core c) lower mantle (mesosphere) d) asthenosphere Diff: 1 ...
Oldest rocks, earliest life, heaviest impacts, and the Hadean
... deformed volcanic and sedimentary rocks, including basalts (with pillow lavas), felsic volcanics, chemical sediments (e.g., chert, banded iron-formation), clastic sediments (now garnet-mica schists) and other minor rock types (for review and references see Appel et al., 2003). The presence of genuin ...
... deformed volcanic and sedimentary rocks, including basalts (with pillow lavas), felsic volcanics, chemical sediments (e.g., chert, banded iron-formation), clastic sediments (now garnet-mica schists) and other minor rock types (for review and references see Appel et al., 2003). The presence of genuin ...
- Wiley Online Library
... 1988], and the tectonics of the Plateau is dominated by four major terranes. From north to south these are the Songpan-Ganzi, Qiangtang, Lhasa, and Himalaya Terranes. All are separated by major sutures (Figure 1) [Yin and Harrison, 2000]. Terrane accretion was initiated in the late Permian when the ...
... 1988], and the tectonics of the Plateau is dominated by four major terranes. From north to south these are the Songpan-Ganzi, Qiangtang, Lhasa, and Himalaya Terranes. All are separated by major sutures (Figure 1) [Yin and Harrison, 2000]. Terrane accretion was initiated in the late Permian when the ...
EGU2017-10612 - CO Meeting Organizer
... anomaly contribution from ice thickness is included in the gravity inversion, as is the contribution from sediments which assumes a compaction controlled sediment density increase with depth. Data used in the gravity inversion are elevation and bathymetry, free-air gravity anomaly, the Bedmap 2 ice ...
... anomaly contribution from ice thickness is included in the gravity inversion, as is the contribution from sediments which assumes a compaction controlled sediment density increase with depth. Data used in the gravity inversion are elevation and bathymetry, free-air gravity anomaly, the Bedmap 2 ice ...
3-D multiobservable probabilistic inversion for the compositional
... and stability, most early, and some recent, ideas favor lithospheric features/processes as the main cause [e.g., Spencer, 1996; McQuarrie and Chase, 2000; Humphreys et al., 2003; Roy et al., 2009; Jones et al., 2015; Molnar et al., 2015]. In these studies, specific inferred features of either the cru ...
... and stability, most early, and some recent, ideas favor lithospheric features/processes as the main cause [e.g., Spencer, 1996; McQuarrie and Chase, 2000; Humphreys et al., 2003; Roy et al., 2009; Jones et al., 2015; Molnar et al., 2015]. In these studies, specific inferred features of either the cru ...
Full Text
... this discrepancy comes from the more storied lifetime of continental lithosphere compared to its oceanic counterpart. Oceanic lithosphere is created at the mid-ocean ridges, from which it ages, cools, and thickens until it meets it demise at subduction zones. Continental lithosphere, on the other ha ...
... this discrepancy comes from the more storied lifetime of continental lithosphere compared to its oceanic counterpart. Oceanic lithosphere is created at the mid-ocean ridges, from which it ages, cools, and thickens until it meets it demise at subduction zones. Continental lithosphere, on the other ha ...
Serpentinization of the forearc mantle
... Department of Geological Sciences, Arizona State University, Tempe, AZ 85287-1404, USA Received 15 July 2002; received in revised form 5 May 2003; accepted 9 May 2003 ...
... Department of Geological Sciences, Arizona State University, Tempe, AZ 85287-1404, USA Received 15 July 2002; received in revised form 5 May 2003; accepted 9 May 2003 ...
On the origin of El Chichón volcano and subduction of
... infiltration and peridotite serpentinization. Then, as the subducting slabs dive into the asthenosphere and become hotter, the stored water is released back into the overlying mantle wedge. Here, the released fluids may partially serpentinize the mantle wedge peridotite, if the temperature is below 60 ...
... infiltration and peridotite serpentinization. Then, as the subducting slabs dive into the asthenosphere and become hotter, the stored water is released back into the overlying mantle wedge. Here, the released fluids may partially serpentinize the mantle wedge peridotite, if the temperature is below 60 ...
Mantle Mixing - Earth and Environmental Sciences
... incompatible and volatile they are expected to be heavily outgassed during melting. Although heavier noble gases from the atmosphere may form a small subducted component (e.g. Porcelli & Wasserburg 1995), He is lost from the atmosphere with a half-life of some 106 years (e.g. Allègre et al 1987; Tor ...
... incompatible and volatile they are expected to be heavily outgassed during melting. Although heavier noble gases from the atmosphere may form a small subducted component (e.g. Porcelli & Wasserburg 1995), He is lost from the atmosphere with a half-life of some 106 years (e.g. Allègre et al 1987; Tor ...
Direct evidence of active deformation in the eastern Indian oceanic
... deformation patterns? In both areas, the deformation has to be linked with the stress regime inherited from the India-Asia collision. North of the western part, the plate boundary is a continentcontinent collision, and north of the eastern part the oceanic plate is subducting beneath a continent, al ...
... deformation patterns? In both areas, the deformation has to be linked with the stress regime inherited from the India-Asia collision. North of the western part, the plate boundary is a continentcontinent collision, and north of the eastern part the oceanic plate is subducting beneath a continent, al ...
Abstract
... The allochthonous cover then developed a vertical north-trending foliation in high-T/lowP conditions as it foundered among buoyant diapirs of remobilised granitoid basement. The nearconstant lateral spacing of the centres of these diapirs, their mushroom shapes, and the absence of contemporaneous vo ...
... The allochthonous cover then developed a vertical north-trending foliation in high-T/lowP conditions as it foundered among buoyant diapirs of remobilised granitoid basement. The nearconstant lateral spacing of the centres of these diapirs, their mushroom shapes, and the absence of contemporaneous vo ...
Structure, tectonic and petrology of mid-oceanic ridges and the
... 70,000 km long mid-oceanic ridges and focus on similar studies made of the Carlsberg–Central Indian Ridges. The potential research areas and problems are also identified for the Indian ridge programme. ANALOGOUS to the Great Wall of China, but several magnitudes larger in dimensions, lie the underwa ...
... 70,000 km long mid-oceanic ridges and focus on similar studies made of the Carlsberg–Central Indian Ridges. The potential research areas and problems are also identified for the Indian ridge programme. ANALOGOUS to the Great Wall of China, but several magnitudes larger in dimensions, lie the underwa ...
First Exam - Practice Test
... d. andesite and diorite. e. All of the above Plutons are a. magma bodies within the deep crust. b. intrusive igneous rocks in the lower mantle. c. magma bodies produced by volcanism. d. igneous rocks produced by fissure eruptions. e. made by contact metamorphism Plate tectonics is important to igneo ...
... d. andesite and diorite. e. All of the above Plutons are a. magma bodies within the deep crust. b. intrusive igneous rocks in the lower mantle. c. magma bodies produced by volcanism. d. igneous rocks produced by fissure eruptions. e. made by contact metamorphism Plate tectonics is important to igneo ...
Nicholson et al., 1997 - University of Minnesota Duluth
... basalt types in comparable stratigraphic positions in other MRS localities around western Lake Superior. Four of these compositions are also recognized at Mamainse Point more than 200 km away in eastern Lake Superior. These regionally correlative basalt compositions provide the basis for determining ...
... basalt types in comparable stratigraphic positions in other MRS localities around western Lake Superior. Four of these compositions are also recognized at Mamainse Point more than 200 km away in eastern Lake Superior. These regionally correlative basalt compositions provide the basis for determining ...
Happy First Day of Februaryана2/1/12 1. Plate Tectonics Review 2
... difference. If it is the same temperature and made of the same material, then the mantle will also have the same density. Therefore the convection currents would STOP moving. ...
... difference. If it is the same temperature and made of the same material, then the mantle will also have the same density. Therefore the convection currents would STOP moving. ...
(Nyasa) Rift US Scientists Donna J. Shillingt
... relatively strong, cold lithosphere. Very little volcanism is associated with rifting, providing a serious test for recent models that require intrusive magmatism to initiate rifting in cold, strong continental lithosphere [Buck, 2004]. Strikingly, the only surface expression of magmatism in this sy ...
... relatively strong, cold lithosphere. Very little volcanism is associated with rifting, providing a serious test for recent models that require intrusive magmatism to initiate rifting in cold, strong continental lithosphere [Buck, 2004]. Strikingly, the only surface expression of magmatism in this sy ...
Mantle plume
A mantle plume is a mechanism proposed in 1971 to explain volcanic regions of the earth that were not thought to be explicable by the then-new theory of plate tectonics. Some such volcanic regions lie far from tectonic plate boundaries, for example, Hawaii. Others represent unusually large-volume volcanism, whether on plate boundaries, e.g. Iceland, or basalt floods such as the Deccan or Siberian traps.A mantle plume is posited to exist where hot rock nucleates at the core-mantle boundary and rises through the Earth's mantle becoming a diapir in the Earth's crust. The currently active volcanic centers are known as ""hot spots"". In particular, the concept that mantle plumes are fixed relative to one another, and anchored at the core-mantle boundary, was thought to provide a natural explanation for the time-progressive chains of older volcanoes seen extending out from some such hot spots, such as the Hawaiian–Emperor seamount chain.The hypothesis of mantle plumes from depth is not universally accepted as explaining all such volcanism. It has required progressive hypothesis-elaboration leading to variant propositions such as mini-plumes and pulsing plumes. Another hypothesis for unusual volcanic regions is the ""Plate model"". This proposes shallower, passive leakage of magma from the mantle onto the Earth's surface where extension of the lithosphere permits it, attributing most volcanism to plate tectonic processes, with volcanoes far from plate boundaries resulting from intraplate extension.