Ignimbrite flare-up and deformation in the southern Sierra Madre
... Therefore this first part of the extensional history remains to be explained. In summary, despite a number of studies published in the last two decades the causes of the ignimbrite flare-up and extension in the SMO are still not completely understood. [4] This paper presents new geologic, geochronol ...
... Therefore this first part of the extensional history remains to be explained. In summary, despite a number of studies published in the last two decades the causes of the ignimbrite flare-up and extension in the SMO are still not completely understood. [4] This paper presents new geologic, geochronol ...
Intrusive vs. Extrusive
... Intrusive vs. Extrusive • Melt that exists below the surface is called _______ and rocks formed by this process are ______ (pushed) into preexisting rocks and referred to as _________ _______ • Melt that is erupted on the surface is called _____ and rocks formed by this process are ________ (pushed) ...
... Intrusive vs. Extrusive • Melt that exists below the surface is called _______ and rocks formed by this process are ______ (pushed) into preexisting rocks and referred to as _________ _______ • Melt that is erupted on the surface is called _____ and rocks formed by this process are ________ (pushed) ...
Arc-Continent collision in Taiwan: New marine observations and
... them forming the slate belt (Ho, 1986; Angelier et al., 1990; Teng et al., 1991; Clark et al., 1993; Tillman and Byrne, 1995). The Western Foothills correspond to a fold-and-thrust belt affecting Oligo-Miocene strata overlain by a 4-km-thick sequence of Pliocene-Quaternary molasse (Lu and Hsü, 1992) ...
... them forming the slate belt (Ho, 1986; Angelier et al., 1990; Teng et al., 1991; Clark et al., 1993; Tillman and Byrne, 1995). The Western Foothills correspond to a fold-and-thrust belt affecting Oligo-Miocene strata overlain by a 4-km-thick sequence of Pliocene-Quaternary molasse (Lu and Hsü, 1992) ...
cyclicity in cordilleran orogenic systems
... are distinguished from other plate boundaries associated with subduction zones by their large amounts of crustal shortening and thickening, high regional elevations and large linear batholith belts1,3–5. A correlation exists between rapid upper-plate motion towards the trench and large-magnitude ret ...
... are distinguished from other plate boundaries associated with subduction zones by their large amounts of crustal shortening and thickening, high regional elevations and large linear batholith belts1,3–5. A correlation exists between rapid upper-plate motion towards the trench and large-magnitude ret ...
Dynamic lithosphere within the Great Basin
... the margins accommodating most of the strain within the region. Late-Cretaceous and Cenozoic volcanism within the Great Basin can be divided into two phases. The first occurred prior to 18 Ma and is part of two concurrent time-transgressive sweeps of volcanism, referred to as the Ignimbrite Flare Up ...
... the margins accommodating most of the strain within the region. Late-Cretaceous and Cenozoic volcanism within the Great Basin can be divided into two phases. The first occurred prior to 18 Ma and is part of two concurrent time-transgressive sweeps of volcanism, referred to as the Ignimbrite Flare Up ...
Workman, Hart, 2005 - University of Maryland, Department of Geology
... material out of the mantle by oceanic and continental crust generation as well as crustal recycling, in so far as the recycled material is well mixed within the upper mantle. In this sense, some of the more complicated processes affecting upper mantle composition are incorporated into the abyssal pe ...
... material out of the mantle by oceanic and continental crust generation as well as crustal recycling, in so far as the recycled material is well mixed within the upper mantle. In this sense, some of the more complicated processes affecting upper mantle composition are incorporated into the abyssal pe ...
Seismic attenuation in the Carpathian bend zone and surroundings
... largely andesitic composition imply the kind of significant fluid fluxing of the upper mantle normally associated with subduction-related arcs. Overall, the elements of normal subduction exist in the Carpathian region, but in detail, many aspects of the tectonics there are not consistent with any si ...
... largely andesitic composition imply the kind of significant fluid fluxing of the upper mantle normally associated with subduction-related arcs. Overall, the elements of normal subduction exist in the Carpathian region, but in detail, many aspects of the tectonics there are not consistent with any si ...
A mantle convection perspective on global tectonics
... The concept of interplay between mantle convection and tectonics goes back to about a century ago, with the proposal that convection currents in the Earth’s mantle drive continental drift and deformation (Holmes, 1931). Since this time, plate tectonic theory has established itself as the fundamental ...
... The concept of interplay between mantle convection and tectonics goes back to about a century ago, with the proposal that convection currents in the Earth’s mantle drive continental drift and deformation (Holmes, 1931). Since this time, plate tectonic theory has established itself as the fundamental ...
Episodic Tremor and Slip
... the GPS unit measured a short-term reversal in the direction of plate motion at this geographical location, representing slow slip on the boundary E The tremor activity, although seen throughout each year, spikes at regular intervals. F.F Each episode of slip occurs at the between the plates. E. sam ...
... the GPS unit measured a short-term reversal in the direction of plate motion at this geographical location, representing slow slip on the boundary E The tremor activity, although seen throughout each year, spikes at regular intervals. F.F Each episode of slip occurs at the between the plates. E. sam ...
Tethyan closure, Andean orogeny, and westward drift of the Pacific
... mantle (Lambeck and Chappell, 2001). The slabs that bound the Pacific upper mantle are slightly discontinuous: upper mantle “leaks”, where the mantle can escape from the Pacific zone via toroidal flow, are mostly restricted to the ~ 6000 km wide southern boundary, which is orthogonal to the slabs, and ...
... mantle (Lambeck and Chappell, 2001). The slabs that bound the Pacific upper mantle are slightly discontinuous: upper mantle “leaks”, where the mantle can escape from the Pacific zone via toroidal flow, are mostly restricted to the ~ 6000 km wide southern boundary, which is orthogonal to the slabs, and ...
Geological Society of America Bulletin
... serpentinite (his Fig. 2, p. 603; Hess 1962), and that the seismic velocity of this layer would be highly variable, depending on the magnitude of serpentinization of the peridotite. He proposed that the interface between the oceanic crust (composed mainly of serpentinite) and the underlying peridoti ...
... serpentinite (his Fig. 2, p. 603; Hess 1962), and that the seismic velocity of this layer would be highly variable, depending on the magnitude of serpentinization of the peridotite. He proposed that the interface between the oceanic crust (composed mainly of serpentinite) and the underlying peridoti ...
Return $200 Question Topic 1
... $400 Question Topic 3 The type of volcano called stratovolcanoes. The most common type; forms from explosive eruptions of pyroclastic material followed by quiet flows of lava. ...
... $400 Question Topic 3 The type of volcano called stratovolcanoes. The most common type; forms from explosive eruptions of pyroclastic material followed by quiet flows of lava. ...
The Azores - Triple Junction and Hot spot
... characteristics of the Azores plateau. Earth and Planetaru Science Letters no 362, p. 258-271 • Babtiste, Allard, Coutinho, Rerreira, Fourré, Queiroz, Gaspar, 2009. Helium isotopes in hydrothermal volcanic fluids of the Azores archipelago • Einarsson, P., 2012. Lecture notes in Current Crustal. Univ ...
... characteristics of the Azores plateau. Earth and Planetaru Science Letters no 362, p. 258-271 • Babtiste, Allard, Coutinho, Rerreira, Fourré, Queiroz, Gaspar, 2009. Helium isotopes in hydrothermal volcanic fluids of the Azores archipelago • Einarsson, P., 2012. Lecture notes in Current Crustal. Univ ...
compositional and thermal differences between lithospheric and
... isotherm of 650±100 °C; within its limits, the lithosphere behaves as a viscous (fragile-elastic) fluid capable to flow but transferring deep-seated heat by conduction from depths where the temperature is close to the temperature of solidus of mantle rocks. The lifetime of TBL depends on its growth ...
... isotherm of 650±100 °C; within its limits, the lithosphere behaves as a viscous (fragile-elastic) fluid capable to flow but transferring deep-seated heat by conduction from depths where the temperature is close to the temperature of solidus of mantle rocks. The lifetime of TBL depends on its growth ...
Whole-mantle convection and plate tectonics
... actually occurring in the mantle (e.g. Liu 1975; Ringwood 1975), and some of the paiameter values may be revised (Jackson, Liebermann & Ringwood 1974), but their values are probably quite representative. The most uncertain of the quantities used by Schubert er al. was the kinematic viscosity, which ...
... actually occurring in the mantle (e.g. Liu 1975; Ringwood 1975), and some of the paiameter values may be revised (Jackson, Liebermann & Ringwood 1974), but their values are probably quite representative. The most uncertain of the quantities used by Schubert er al. was the kinematic viscosity, which ...
Free Sample
... since the centers of the glaciers would have been in the ocean if they were not. Also, the continents, such as South America and Africa, match like a jigsaw puzzle. Similar fossil plant and animals are separated by oceans leading to the assumption that they must have lived in adjacent regions when t ...
... since the centers of the glaciers would have been in the ocean if they were not. Also, the continents, such as South America and Africa, match like a jigsaw puzzle. Similar fossil plant and animals are separated by oceans leading to the assumption that they must have lived in adjacent regions when t ...
Degree-one mantle convection: Dependence on
... has been put forth to understand the physics behind generating larger wavelength flow patterns than those observed in simple experiments. [5] A fundamental question is whether observed large wavelength mantle flow results from the complicated brittleelastic physics of the lithosphere or whether the ...
... has been put forth to understand the physics behind generating larger wavelength flow patterns than those observed in simple experiments. [5] A fundamental question is whether observed large wavelength mantle flow results from the complicated brittleelastic physics of the lithosphere or whether the ...
Experimental tests of simple models for the dynamics
... oceanic plate boundaries and is readily testable by analogue laboratory models. The theoretical problem is defined in Fig. 3(a) and the experimental analogue is shown in Fig. 3(b). The position of the pole of rotation of component plate A relative to component plate B is defined to be (x 0 , y 0 ), ...
... oceanic plate boundaries and is readily testable by analogue laboratory models. The theoretical problem is defined in Fig. 3(a) and the experimental analogue is shown in Fig. 3(b). The position of the pole of rotation of component plate A relative to component plate B is defined to be (x 0 , y 0 ), ...
Dynamic topography above retreating subduction zones
... the topography developed above them. A theoretical model of subduction, inversion of ␦VP seismic data, and observations of gravity and bathymetry data above several subduction systems show that slabinduced mantle flow is a prominent control on the topographic signal in the vicinity of subduction bou ...
... the topography developed above them. A theoretical model of subduction, inversion of ␦VP seismic data, and observations of gravity and bathymetry data above several subduction systems show that slabinduced mantle flow is a prominent control on the topographic signal in the vicinity of subduction bou ...
Evolution of the Neogene-Pleistocene Basins of Macedonia
... in the Vardar zone and the Serbo-Macedonian massif. The oldest volcanic rocks occur in the areas of Bucim, Damjan, and Borov Dol (26.4–24.9 Ma), Kratovo and Zletovo (32–29 ± 2 Ma to 16 ± 2.0 Ma) and in the zone Toranica, Sasa, and Delcevo–Pechevo (25–17 Ma; Fig. 3). These older volcanic rocks are ov ...
... in the Vardar zone and the Serbo-Macedonian massif. The oldest volcanic rocks occur in the areas of Bucim, Damjan, and Borov Dol (26.4–24.9 Ma), Kratovo and Zletovo (32–29 ± 2 Ma to 16 ± 2.0 Ma) and in the zone Toranica, Sasa, and Delcevo–Pechevo (25–17 Ma; Fig. 3). These older volcanic rocks are ov ...
Volcanism in the Afar Rift sustained by decompression melting with
... is one mechanism that has been presented to explain rift initiation in magmatic rift zones such as Afar1,2 . However, the location(s) and degree of influence of plume material in the Afar Rift system at present is debated (for example, refs 2,3). Knowing the thickness of the lithosphere and the dept ...
... is one mechanism that has been presented to explain rift initiation in magmatic rift zones such as Afar1,2 . However, the location(s) and degree of influence of plume material in the Afar Rift system at present is debated (for example, refs 2,3). Knowing the thickness of the lithosphere and the dept ...
Thermal evolution of the Earth as recorded by komatiites
... that komatiites were produced at high temperatures (V1650‡C) and estimated a depth of 150 km or greater for melt segregation from the source. This initial conclusion of a deep melting origin was revisited in light of new evidence from experimental studies of the best available estimate of the primar ...
... that komatiites were produced at high temperatures (V1650‡C) and estimated a depth of 150 km or greater for melt segregation from the source. This initial conclusion of a deep melting origin was revisited in light of new evidence from experimental studies of the best available estimate of the primar ...
Geology
Geology (from the Greek γῆ, gē, i.e. ""earth"" and -λoγία, -logia, i.e. ""study of, discourse"") is an earth science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which they change. Geology can also refer generally to the study of the solid features of any celestial body (such as the geology of the Moon or Mars).Geology gives insight into the history of the Earth by providing the primary evidence for plate tectonics, the evolutionary history of life, and past climates. Geology is important for mineral and hydrocarbon exploration and exploitation, evaluating water resources, understanding of natural hazards, the remediation of environmental problems, and for providing insights into past climate change. Geology also plays a role in geotechnical engineering and is a major academic discipline.