The Patrimonial Value of the Betic Ophiolites: Rocks from the
... together with oceanic metasediments. They form a tectonic Unit of the Mulhacén Complex in the Betic Cordillera (SE Spain), intercalated between two crustal units named Caldera (below) and Sabinas (above). A comprehensive review of the petrological, geochemical and geochronological characteristics of ...
... together with oceanic metasediments. They form a tectonic Unit of the Mulhacén Complex in the Betic Cordillera (SE Spain), intercalated between two crustal units named Caldera (below) and Sabinas (above). A comprehensive review of the petrological, geochemical and geochronological characteristics of ...
Alps vs. Apennines - Dipartimento di Scienze della Terra
... Alps and Apennines developed along opposite subductions, which inverted the tethyan passive continental margins located along the boundaries of Europe, Africa and the Adriatic plates. The Alps have higher morphological and structural elevation, two shallow, slow subsiding foreland basins. The Apenni ...
... Alps and Apennines developed along opposite subductions, which inverted the tethyan passive continental margins located along the boundaries of Europe, Africa and the Adriatic plates. The Alps have higher morphological and structural elevation, two shallow, slow subsiding foreland basins. The Apenni ...
Workshop on the Rio Grande Rift
... Remote sensing (R-S) was seen as a potential overview tool to delineate large scale regional features in ...
... Remote sensing (R-S) was seen as a potential overview tool to delineate large scale regional features in ...
Weakening of the subduction interface and its effects on surface
... pling, a feedback mechanism can be qualitatively established as follows. [7] The cooling effect of the subducting slab results in relatively low temperatures in the most seaward part of the mantle wedge. Fluids released from the subducting slab during metamorphic dehydration will allow weak hydrous ...
... pling, a feedback mechanism can be qualitatively established as follows. [7] The cooling effect of the subducting slab results in relatively low temperatures in the most seaward part of the mantle wedge. Fluids released from the subducting slab during metamorphic dehydration will allow weak hydrous ...
H2O subduction beyond arcs
... diverges from these earlier efforts by considering a broader range of bulk compositions more representative of the variety of rocks being subducted by calculating the flux for each subduction zone individually, and by including the effects of subduction erosion and continental collisions. [4] A pres ...
... diverges from these earlier efforts by considering a broader range of bulk compositions more representative of the variety of rocks being subducted by calculating the flux for each subduction zone individually, and by including the effects of subduction erosion and continental collisions. [4] A pres ...
Sample Midterm/Final
... the rate of sea floor spreading exceeds the rate of subduction at the convergent margin b. the rate of sea floor spreading is less than the rate of subduction at the convergent margin correct answer c. sea floor spreading will cease because the asthenosphere convection will shut down d the Juan de F ...
... the rate of sea floor spreading exceeds the rate of subduction at the convergent margin b. the rate of sea floor spreading is less than the rate of subduction at the convergent margin correct answer c. sea floor spreading will cease because the asthenosphere convection will shut down d the Juan de F ...
Fault on-off versus strain rate and earthquakes energy
... where the strain rate was lower during the interseismic stage (Fig. 2). A second example is represented by the antithetic normal fault that slipped during the 40-s sub-event of the Irpinia 1980 earthquake in southern Italy (Pingue and De Natale, 1993). During the coseismic stage, the weight of the b ...
... where the strain rate was lower during the interseismic stage (Fig. 2). A second example is represented by the antithetic normal fault that slipped during the 40-s sub-event of the Irpinia 1980 earthquake in southern Italy (Pingue and De Natale, 1993). During the coseismic stage, the weight of the b ...
Upper mantle structure beneath the eastern Colorado Plateau and
... uppermost mantle density contrasts using Bouguer gravity along five parallel profiles across the Colorado Plateau and validate our models by converting modeled density contrasts to seismic velocity variations for comparison with regional seismic data, as well as comparing modeled densities to calcul ...
... uppermost mantle density contrasts using Bouguer gravity along five parallel profiles across the Colorado Plateau and validate our models by converting modeled density contrasts to seismic velocity variations for comparison with regional seismic data, as well as comparing modeled densities to calcul ...
Upper mantle structure beneath the eastern Colorado Plateau and
... uppermost mantle density contrasts using Bouguer gravity along five parallel profiles across the Colorado Plateau and validate our models by converting modeled density contrasts to seismic velocity variations for comparison with regional seismic data, as well as comparing modeled densities to calcul ...
... uppermost mantle density contrasts using Bouguer gravity along five parallel profiles across the Colorado Plateau and validate our models by converting modeled density contrasts to seismic velocity variations for comparison with regional seismic data, as well as comparing modeled densities to calcul ...
Antigorite Peridotite, Metaserpentinite, and other
... (1979) concluded that at least the first three of these hydrous minerals formed in the mantle before eruption, but that evidence for a mantle origin of the antigorite was ambiguous. Because there is no evidence that the host SUM was ever a magma, and because the genetic relationships between the per ...
... (1979) concluded that at least the first three of these hydrous minerals formed in the mantle before eruption, but that evidence for a mantle origin of the antigorite was ambiguous. Because there is no evidence that the host SUM was ever a magma, and because the genetic relationships between the per ...
Draft 2.5 - posted 15 June 2014 /2500k
... Global volcanic eruptions of Volcanic Explosivity Index (VEI) category 5>VEI≥6 also appear to be correlated to the MGC of drift direction. Three of these five eruptions occurred 6.6–12.0 years after site coincidence with the drift MGC, averaging 9.1 years afterward. The fourth, a 1902.8 eruption in ...
... Global volcanic eruptions of Volcanic Explosivity Index (VEI) category 5>VEI≥6 also appear to be correlated to the MGC of drift direction. Three of these five eruptions occurred 6.6–12.0 years after site coincidence with the drift MGC, averaging 9.1 years afterward. The fourth, a 1902.8 eruption in ...
The West Philippine Basin: An Eocene to early Oligocene back arc
... ODE: Oki-Daito Escarpment, TF: Transform Fault, NTD: Non-Transform Discontinuity, FR: Failed Rift. Rise, fan-shaped abyssal hills are found within a 1000-km2 area that is bordered by elongated valleys. They reveal the presence of a microplate which developed between two active spreading centers (Fig ...
... ODE: Oki-Daito Escarpment, TF: Transform Fault, NTD: Non-Transform Discontinuity, FR: Failed Rift. Rise, fan-shaped abyssal hills are found within a 1000-km2 area that is bordered by elongated valleys. They reveal the presence of a microplate which developed between two active spreading centers (Fig ...
2. Geology and tectonics of the Aegean - diss.fu
... Eurasian plate during the last 92 My (Müller & Kahle, 1993). The existence of a calcalkaline inner volcanic arc, the spatial distribution of earthquakes and detailed tomographic studies indicate the existence of a northward-dipping subducted slab beneath this region (African plate beneath Eurasian p ...
... Eurasian plate during the last 92 My (Müller & Kahle, 1993). The existence of a calcalkaline inner volcanic arc, the spatial distribution of earthquakes and detailed tomographic studies indicate the existence of a northward-dipping subducted slab beneath this region (African plate beneath Eurasian p ...
3.20 Trace Element and Isotopic Fluxes
... and metamorphism along the subduction pathway. The focus in this contribution is largely on the chemical and isotopic tracers commonly employed to elucidate chemical cycling in subduction zones based on study of arc lavas, and on discussion of metamorphic suites for which it is possible to evaluate ...
... and metamorphism along the subduction pathway. The focus in this contribution is largely on the chemical and isotopic tracers commonly employed to elucidate chemical cycling in subduction zones based on study of arc lavas, and on discussion of metamorphic suites for which it is possible to evaluate ...
Tsunamigenic earthquakes in the Gulf of Cadiz
... GPS observations, the Nubia-Eurasia convergence is accommodated partially in NW Morocco and partially in the Gulf of Cadiz over an area > 200 km wide. Other consequences of the modelling results by Cunha et al. (2012) were that the SWIM lineaments do not represent a mature fracture zone cutting thro ...
... GPS observations, the Nubia-Eurasia convergence is accommodated partially in NW Morocco and partially in the Gulf of Cadiz over an area > 200 km wide. Other consequences of the modelling results by Cunha et al. (2012) were that the SWIM lineaments do not represent a mature fracture zone cutting thro ...
Post glacial rebounds measure the viscosity of the lithosphere
... uncertainty indicates that a homogeneous model can fully explain the observed uplift for the postglacial period from 7944 to 87 BP years and that the possible contribution of a low viscosity layer to the uplift can be excluded. This also means that the low viscosity models should be discredited. 3. ...
... uncertainty indicates that a homogeneous model can fully explain the observed uplift for the postglacial period from 7944 to 87 BP years and that the possible contribution of a low viscosity layer to the uplift can be excluded. This also means that the low viscosity models should be discredited. 3. ...
Upper mantle anisotropy beneath Australia and Tahiti from P
... station TAU (Tasmania), which may be due to plate-motion-driven alignment of olivine crystals in the asthenosphere. Interestingly, measurements of SKS splitting at Tahiti (French Polynesia) show an apparent isotropy, whereas an inversion of Ppol observations at PPTL seismic station located in Tahiti ...
... station TAU (Tasmania), which may be due to plate-motion-driven alignment of olivine crystals in the asthenosphere. Interestingly, measurements of SKS splitting at Tahiti (French Polynesia) show an apparent isotropy, whereas an inversion of Ppol observations at PPTL seismic station located in Tahiti ...
The Volume and Composition of Melt Generated
... system offset in the same way and if so how? What happens when a ridge jumps and leaving a fossil ridge and starting a new one, sometimes thousands of kilometres away? Does the hot sheet move also, and if so how? These and other problems with the ideas in Fig. 2(a) suggested that they should be exam ...
... system offset in the same way and if so how? What happens when a ridge jumps and leaving a fossil ridge and starting a new one, sometimes thousands of kilometres away? Does the hot sheet move also, and if so how? These and other problems with the ideas in Fig. 2(a) suggested that they should be exam ...
PDF
... 3He/4He data to propose that the distribution of high 3He/4He ratios indicates the direction of flow of the plume-enriched mantle, that is, from the Samoan plume into the Lau Basin. Macpherson et al. [1998] similarly used He isotopes to infer a plume influence in Manus Basin basalts. Useful though i ...
... 3He/4He data to propose that the distribution of high 3He/4He ratios indicates the direction of flow of the plume-enriched mantle, that is, from the Samoan plume into the Lau Basin. Macpherson et al. [1998] similarly used He isotopes to infer a plume influence in Manus Basin basalts. Useful though i ...
Plate tectonics
Plate tectonics (from the Late Latin tectonicus, from the Greek: τεκτονικός ""pertaining to building"") is a scientific theory that describes the large-scale motion of Earth's lithosphere. This theoretical model builds on the concept of continental drift which was developed during the first few decades of the 20th century. The geoscientific community accepted the theory after the concepts of seafloor spreading were later developed in the late 1950s and early 1960s.The lithosphere, which is the rigid outermost shell of a planet (on Earth, the crust and upper mantle), is broken up into tectonic plates. On Earth, there are seven or eight major plates (depending on how they are defined) and many minor plates. Where plates meet, their relative motion determines the type of boundary; convergent, divergent, or transform. Earthquakes, volcanic activity, mountain-building, and oceanic trench formation occur along these plate boundaries. The lateral relative movement of the plates typically varies from zero to 100 mm annually.Tectonic plates are composed of oceanic lithosphere and thicker continental lithosphere, each topped by its own kind of crust. Along convergent boundaries, subduction carries plates into the mantle; the material lost is roughly balanced by the formation of new (oceanic) crust along divergent margins by seafloor spreading. In this way, the total surface of the globe remains the same. This prediction of plate tectonics is also referred to as the conveyor belt principle. Earlier theories (that still have some supporters) propose gradual shrinking (contraction) or gradual expansion of the globe.Tectonic plates are able to move because the Earth's lithosphere has greater strength than the underlying asthenosphere. Lateral density variations in the mantle result in convection. Plate movement is thought to be driven by a combination of the motion of the seafloor away from the spreading ridge (due to variations in topography and density of the crust, which result in differences in gravitational forces) and drag, with downward suction, at the subduction zones. Another explanation lies in the different forces generated by the rotation of the globe and the tidal forces of the Sun and Moon. The relative importance of each of these factors and their relationship to each other is unclear, and still the subject of much debate.