Thesis - UvA-DARE - University of Amsterdam
... sediment particles by bioturbating fauna that functions as a “conveyer belt” (Jørgensen & Nelson 2004; Fig. 2). Iron sulfide and pyrite are transported up to the sediment surface where they are reoxidized to iron (hydro)oxide: FeS2 + 5/2 H 2O + 15/4 O2 à FeOOH + 4H + + 2SO42- (19) Iron (hydro)oxid ...
... sediment particles by bioturbating fauna that functions as a “conveyer belt” (Jørgensen & Nelson 2004; Fig. 2). Iron sulfide and pyrite are transported up to the sediment surface where they are reoxidized to iron (hydro)oxide: FeS2 + 5/2 H 2O + 15/4 O2 à FeOOH + 4H + + 2SO42- (19) Iron (hydro)oxid ...
Mantle Convection in the Earth and Planets - U
... convection is the primary mechanism for the transport of heat from the Earth’s deep interior to its surface, it is the underlying cause of plate tectonics, formation and drift of continents, volcanism, earthquakes, and mountain building processes. It also shapes the gravitational and magnetic fields ...
... convection is the primary mechanism for the transport of heat from the Earth’s deep interior to its surface, it is the underlying cause of plate tectonics, formation and drift of continents, volcanism, earthquakes, and mountain building processes. It also shapes the gravitational and magnetic fields ...
- ERA - University of Alberta
... lithosphere; crustal flow in a lower-crust channel can cause the surface to invert to become a topographic high. Magmatism caused by lithosphere removal depends on the removal style and the initial thermal structure of lithosphere. During a Rayleigh-Taylor instability (drip), three types of magmas a ...
... lithosphere; crustal flow in a lower-crust channel can cause the surface to invert to become a topographic high. Magmatism caused by lithosphere removal depends on the removal style and the initial thermal structure of lithosphere. During a Rayleigh-Taylor instability (drip), three types of magmas a ...
Global geochemical variation of mid-ocean ridge basalts - UiO
... through the mantle via pelagic sediments. On a broad scale, increasing degree of partial melting is reflected by a minor increase in the fractionation-corrected Ca/Al ratio, which in turn is positively correlated with the spreading rate in the sequence from the South-West Indian Ridge (SWIR, full sp ...
... through the mantle via pelagic sediments. On a broad scale, increasing degree of partial melting is reflected by a minor increase in the fractionation-corrected Ca/Al ratio, which in turn is positively correlated with the spreading rate in the sequence from the South-West Indian Ridge (SWIR, full sp ...
The stability of arc lower crust: Insights from the Talkeetna Arc
... Talkeetna section were likely denser than the underlying mantle, while the remaining gabbronorites are neutrally or slightly positively buoyant. In addition, we show that arc lower crustal rock compositions that are denser than the underlying mantle generally have P-wave velocities > 7.4 km/s. Becau ...
... Talkeetna section were likely denser than the underlying mantle, while the remaining gabbronorites are neutrally or slightly positively buoyant. In addition, we show that arc lower crustal rock compositions that are denser than the underlying mantle generally have P-wave velocities > 7.4 km/s. Becau ...
Workshop Report - Consortium for Ocean Leadership
... processes of mantle melting, melt aggregation and transport have undergone large advances with the integration of mantle geochemistry and rock physics. There was considerable discussion of the origin and consequences of focused viscous deformation along mantle shear zones, with application to meltin ...
... processes of mantle melting, melt aggregation and transport have undergone large advances with the integration of mantle geochemistry and rock physics. There was considerable discussion of the origin and consequences of focused viscous deformation along mantle shear zones, with application to meltin ...
Origin and models of oceanic transform faults. Tectonophysics, 522
... first have seismic moment release one-two orders higher; their contribution into the total seismic budget of mid ocean ridges increases with higher spreading rate. The relationships between the seismic moment release, fault length and spreading rate are quite different for transform and rift parts of ...
... first have seismic moment release one-two orders higher; their contribution into the total seismic budget of mid ocean ridges increases with higher spreading rate. The relationships between the seismic moment release, fault length and spreading rate are quite different for transform and rift parts of ...
The nails
... Treatment Manicuring of the cuticle should cease. The hands should be kept warm and dry, and the damaged nail folds packed several times a day with an imidazole cream and if swabs confirm candida, a 2-week course of itraconazole . ► Dermatophyte infections The common dermatophytes that cause tinea p ...
... Treatment Manicuring of the cuticle should cease. The hands should be kept warm and dry, and the damaged nail folds packed several times a day with an imidazole cream and if swabs confirm candida, a 2-week course of itraconazole . ► Dermatophyte infections The common dermatophytes that cause tinea p ...
ecology of cold seep sediments
... species diversity associated with carbonate mounds and coral reefs in the North Atlantic and Gulf of Mexico. Sibuet et al. (1988) note the occurrence of Calyptogena species on a broad range of substrata in the Japan Trench, including sediments, mudstone, gravel, talus and vertical rock ledges. In su ...
... species diversity associated with carbonate mounds and coral reefs in the North Atlantic and Gulf of Mexico. Sibuet et al. (1988) note the occurrence of Calyptogena species on a broad range of substrata in the Japan Trench, including sediments, mudstone, gravel, talus and vertical rock ledges. In su ...
relationships between nodule genesis and topography in the
... On the cross-section, the grabens are predominantly trough-like. The grabens may contain depressions up to 210 m deep, their size varying from 0.8 x 1.4 km to 3.0 x 18 km. The depression axes are curved in outline; certain wide grabens have several axes. The graben walls are steep, occasionally almo ...
... On the cross-section, the grabens are predominantly trough-like. The grabens may contain depressions up to 210 m deep, their size varying from 0.8 x 1.4 km to 3.0 x 18 km. The depression axes are curved in outline; certain wide grabens have several axes. The graben walls are steep, occasionally almo ...
Geophysical and Petrological Constraints on Ocean Plate Dynamics
... resulting two dimensional conductivity model shows a simple layered structure. By applying petrological constraints, I conclude that the upper asthenosphere does not contain substantial melt, which suggests that either a thermal or hydration mechanism supports plate motion. Oceanic plate motion has ...
... resulting two dimensional conductivity model shows a simple layered structure. By applying petrological constraints, I conclude that the upper asthenosphere does not contain substantial melt, which suggests that either a thermal or hydration mechanism supports plate motion. Oceanic plate motion has ...
workshop report
... processed tuna; the same might be said about juvenile versus mature continental crust. Although there are many examples of accreted arc crust on the margins of continents, during- and/or post-collision geochemical changes are widespread (e.g., DeBari & Greene, 2011), and we don’t have the ability to ...
... processed tuna; the same might be said about juvenile versus mature continental crust. Although there are many examples of accreted arc crust on the margins of continents, during- and/or post-collision geochemical changes are widespread (e.g., DeBari & Greene, 2011), and we don’t have the ability to ...
Volatile Cycling of H2O, CO2, F, and Cl in the HIMU Mantle: A New
... subducted slab reservoir, which evolves highly radiogenic Pb-isotope compositions over time [Hofmann and White, 1982; Zindler and Hart, 1986; Hauri and Hart, 1993; Kelley et al., 2005; Hanyu et al., 2011, 2014]. Alternatively, the high U/Pb inferred for the HIMU mantle source may be a result of U in ...
... subducted slab reservoir, which evolves highly radiogenic Pb-isotope compositions over time [Hofmann and White, 1982; Zindler and Hart, 1986; Hauri and Hart, 1993; Kelley et al., 2005; Hanyu et al., 2011, 2014]. Alternatively, the high U/Pb inferred for the HIMU mantle source may be a result of U in ...
The Upper Mantle Geoid: Implications for Continental Structure and
... very long wavelength geoid (degree/order less than 5) thought to be controlled by topographic relief of less than 3 km at the core-mantle boundary (Bowin, 1986). Removal of the signal from subducted slabs (Chase, 1979; Crough, 1979; Crough and Jurdy, 1980; Kaula, 1967; Hager, 1984) demonstrates that ...
... very long wavelength geoid (degree/order less than 5) thought to be controlled by topographic relief of less than 3 km at the core-mantle boundary (Bowin, 1986). Removal of the signal from subducted slabs (Chase, 1979; Crough, 1979; Crough and Jurdy, 1980; Kaula, 1967; Hager, 1984) demonstrates that ...
Full text PDF - Geochemical Perspectives
... manifest in variations in stable isotope ratios that could only have been produced at or near the surface of the Earth. In addition to a recycled component, many plumes also contain a quite primitive component, manifested primarily in their noble gas isotope ratios. The primitive component seems mo ...
... manifest in variations in stable isotope ratios that could only have been produced at or near the surface of the Earth. In addition to a recycled component, many plumes also contain a quite primitive component, manifested primarily in their noble gas isotope ratios. The primitive component seems mo ...
univERsity oF copEnhAGEn
... of mantle upwelling (plumes) with continental lithosphere may play an important role in lithosphere growth, modification, and destruction both at plate margins and in intraplate regions. Mantle melting and infiltration of basaltic magmas are not restricted to the mantle part of the lithosphere, but of ...
... of mantle upwelling (plumes) with continental lithosphere may play an important role in lithosphere growth, modification, and destruction both at plate margins and in intraplate regions. Mantle melting and infiltration of basaltic magmas are not restricted to the mantle part of the lithosphere, but of ...
Moho and magmatic underplating
... of mantle upwelling (plumes) with continental lithosphere may play an important role in lithosphere growth, modification, and destruction both at plate margins and in intraplate regions. Mantle melting and infiltration of basaltic magmas are not restricted to the mantle part of the lithosphere, but of ...
... of mantle upwelling (plumes) with continental lithosphere may play an important role in lithosphere growth, modification, and destruction both at plate margins and in intraplate regions. Mantle melting and infiltration of basaltic magmas are not restricted to the mantle part of the lithosphere, but of ...
Three-dimensional crustal structure of the Mariana island arc from
... Figure 2. Location of the grid of airgun shot lines, 52 ocean bottom seismometers (OBS) receivers, 2 land seismometers, and the separately recorded, Japan Agency for Marine-Earth Science and Technology (JAMSTEC) 2-D OBS/airgun profile, superimposed on the bathymetry of Mariana volcanic arc at approx ...
... Figure 2. Location of the grid of airgun shot lines, 52 ocean bottom seismometers (OBS) receivers, 2 land seismometers, and the separately recorded, Japan Agency for Marine-Earth Science and Technology (JAMSTEC) 2-D OBS/airgun profile, superimposed on the bathymetry of Mariana volcanic arc at approx ...
Ascent of the ultrahigh-pressure Western Gneiss Region, Norway.
... is significant because it is becoming clear that a typical orogenic belt experiences multiple (U)HP events. Consider four examples. (1) In the Alps, there were at least four stages of (U)HP metamorphism: Cretaceous in the Penninic unit of the eastern Alps, ca. 65 Ma in the Austro-Alpine units, ca. 4 ...
... is significant because it is becoming clear that a typical orogenic belt experiences multiple (U)HP events. Consider four examples. (1) In the Alps, there were at least four stages of (U)HP metamorphism: Cretaceous in the Penninic unit of the eastern Alps, ca. 65 Ma in the Austro-Alpine units, ca. 4 ...
as a PDF
... mapping, we determined that the section consists of thrustbounded piles of imbricated tectonic slices cut by many layerparallel faults. The repeating basalt-sediment sequence was the result of tectonic overlapping of the same stratigraphic units (Ohta et al., 1996; Fig. 1a). Each tectonic slice exhi ...
... mapping, we determined that the section consists of thrustbounded piles of imbricated tectonic slices cut by many layerparallel faults. The repeating basalt-sediment sequence was the result of tectonic overlapping of the same stratigraphic units (Ohta et al., 1996; Fig. 1a). Each tectonic slice exhi ...
Primitive off-rift basalts from Iceland and Jan Mayen: Os
... related to the presence of enriched material from the plume. One or more depleted end-members also exist. Some studies have argued for the presence of a depleted end-member that is intrinsic to the upwelling plume, and thus distinct from that within the convecting upper mantle source for Atlantic MO ...
... related to the presence of enriched material from the plume. One or more depleted end-members also exist. Some studies have argued for the presence of a depleted end-member that is intrinsic to the upwelling plume, and thus distinct from that within the convecting upper mantle source for Atlantic MO ...
Hotspots and Melting anomalies - Earth and Environmental Sciences
... established the concept of “hotspot” as a broad swelling of topography capped by volcanism, which, combined with plate motion, generates volcanoes aligned in a chain and with ages that progress monotonically. In some cases, these chains project back to massive volcanic plateaus, or large igneous pro ...
... established the concept of “hotspot” as a broad swelling of topography capped by volcanism, which, combined with plate motion, generates volcanoes aligned in a chain and with ages that progress monotonically. In some cases, these chains project back to massive volcanic plateaus, or large igneous pro ...
Thesis pdf
... lithosphere is up to ~90 km thinner, especially below the Central Iran and Alborz Mountains. The lithosphere-asthenosphere boundary (LAB) shows different geometries between the two transects. In the northern profile (northern Zagros), the LAB rises sharply below the Sanandaj Sirjan Zone in a narrow ...
... lithosphere is up to ~90 km thinner, especially below the Central Iran and Alborz Mountains. The lithosphere-asthenosphere boundary (LAB) shows different geometries between the two transects. In the northern profile (northern Zagros), the LAB rises sharply below the Sanandaj Sirjan Zone in a narrow ...
Neotectonic and Paleoseismic Onshore-Offshore integrated study of the Carboneras Fault (Eastern
... alluvial fans overlie the Neogene basement. Close to the range, the A1 alluvial fans show stratified and imbricated large pebbles and locally cross bedding, which indicate a stream-flood mode of deposition. Distally, clays and sands with interbedded thin channel-shaped layers of well rounded pebbles ...
... alluvial fans overlie the Neogene basement. Close to the range, the A1 alluvial fans show stratified and imbricated large pebbles and locally cross bedding, which indicate a stream-flood mode of deposition. Distally, clays and sands with interbedded thin channel-shaped layers of well rounded pebbles ...
The Central Asia collision zone: numerical present-day kinematics
... lithosphere is up to ~90 km thinner, especially below the Central Iran and Alborz Mountains. The lithosphere-asthenosphere boundary (LAB) shows different geometries between the two transects. In the northern profile (northern Zagros), the LAB rises sharply below the Sanandaj Sirjan Zone in a narrow ...
... lithosphere is up to ~90 km thinner, especially below the Central Iran and Alborz Mountains. The lithosphere-asthenosphere boundary (LAB) shows different geometries between the two transects. In the northern profile (northern Zagros), the LAB rises sharply below the Sanandaj Sirjan Zone in a narrow ...
Oceanic trench
The oceanic trenches are hemispheric-scale long but narrow topographic depressions of the sea floor. They are also the deepest parts of the ocean floor. Oceanic trenches are a distinctive morphological feature of convergent plate boundaries, along which lithospheric plates move towards each other at rates that vary from a few mm to over ten cm per year. A trench marks the position at which the flexed, subducting slab begins to descend beneath another lithospheric slab. Trenches are generally parallel to a volcanic island arc, and about 200 km (120 mi) from a volcanic arc. Oceanic trenches typically extend 3 to 4 km (1.9 to 2.5 mi) below the level of the surrounding oceanic floor. The greatest ocean depth to be sounded is in the Challenger Deep of the Mariana Trench, at a depth of 11,034 m (36,201 ft) below sea level. Oceanic lithosphere moves into trenches at a global rate of about 3 km2/yr.