Consulta: creatorFacets:"Le Pichon, Xavier" Registros recuperados
... Autores: Olivet, Jean-louis; Sichler, Bertrand; Thonon, Pierre; Le Pichon, Xavier; Martinais, Guy; Pautot, Guy. The Gibbs fracture moves the central Rift of the Mid-Atlantic Ridge 370 km to the left at latitude 53O north. It is the only fracture located between Europe and America that can be compare ...
... Autores: Olivet, Jean-louis; Sichler, Bertrand; Thonon, Pierre; Le Pichon, Xavier; Martinais, Guy; Pautot, Guy. The Gibbs fracture moves the central Rift of the Mid-Atlantic Ridge 370 km to the left at latitude 53O north. It is the only fracture located between Europe and America that can be compare ...
Anammox bacteria disguised as denitrifiers: nitrate reduction to
... ammonium also proceeds in two steps: first nitrate is reduced to nitrite, then nitrite is reduced to ammonium. In our experiments nitrate reduction to nitrite started immediately; however, N2 evolved only after a lag phase of 120 min. Also the accumulation of nitrite only occurred in the absence of ...
... ammonium also proceeds in two steps: first nitrate is reduced to nitrite, then nitrite is reduced to ammonium. In our experiments nitrate reduction to nitrite started immediately; however, N2 evolved only after a lag phase of 120 min. Also the accumulation of nitrite only occurred in the absence of ...
On the role of subducting oceanic plateaus in the development of
... possible mechanism to explain the occurrence of flat subduction and related absence of arc magmatism below Peru, Central Chile and at the Nankai Trough (Japan). Their extra compositional buoyancy could prohibit the slab from sinking into the mantle. With a numerical thermochemical convection model, ...
... possible mechanism to explain the occurrence of flat subduction and related absence of arc magmatism below Peru, Central Chile and at the Nankai Trough (Japan). Their extra compositional buoyancy could prohibit the slab from sinking into the mantle. With a numerical thermochemical convection model, ...
A global-scale plate reorganization event at 105−100Ma
... A major plate reorganization is postulated to have occurred at approximately 100 Ma. However, this reorganization has received limited attention, despite being associated with the most prominent suite of fracture zone bends on the planet and many other geological events. We investigate tectonic even ...
... A major plate reorganization is postulated to have occurred at approximately 100 Ma. However, this reorganization has received limited attention, despite being associated with the most prominent suite of fracture zone bends on the planet and many other geological events. We investigate tectonic even ...
Geological understanding of plate tectonics
... lithosphere because of lacking significant compositional buoyancy contrast. In normal ocean basins, there is generally no location with large within-lithosphere thermal buoyancy contrast either that could favor subduction initiation. The Romanche transform in the equatorial Atlantic may be the only ...
... lithosphere because of lacking significant compositional buoyancy contrast. In normal ocean basins, there is generally no location with large within-lithosphere thermal buoyancy contrast either that could favor subduction initiation. The Romanche transform in the equatorial Atlantic may be the only ...
Subduction of young oceanic plates: A numerical study with
... Figure 1. Initial configuration of the numerical model (see text for details). White lines are isotherms shown for increments of 200°C starting from 100°C. Colors indicate materials (e.g., rock type or melt) which appear in Figures 2–7. High‐resolution central 600 × 150 km part of the original 4000 ...
... Figure 1. Initial configuration of the numerical model (see text for details). White lines are isotherms shown for increments of 200°C starting from 100°C. Colors indicate materials (e.g., rock type or melt) which appear in Figures 2–7. High‐resolution central 600 × 150 km part of the original 4000 ...
Nitrogen isotopes in bulk marine sediment: linking seafloor
... buried sediment record. Meanwhile, gradual δ 15 N decreases over multiple glacial–interglacial cycles appear to reflect post-depositional alteration in records from the deep sea (below 2000 m). We suggest a simple conceptual model to explain these 100-kyr-timescale changes in well-oxygenated, slowly ...
... buried sediment record. Meanwhile, gradual δ 15 N decreases over multiple glacial–interglacial cycles appear to reflect post-depositional alteration in records from the deep sea (below 2000 m). We suggest a simple conceptual model to explain these 100-kyr-timescale changes in well-oxygenated, slowly ...
1 Bacterial vs. zooplankton control of sinking particle
... Depth integrated bacteria respiration (BR) and carbon demand (BCD) was based on our measures of bacteria production (BP) at discrete depths throughout the water column, and ...
... Depth integrated bacteria respiration (BR) and carbon demand (BCD) was based on our measures of bacteria production (BP) at discrete depths throughout the water column, and ...
Review of Ocean Literacy in European Maritime Policy
... anticipated that creating a more ocean literate society in Europe will result in increased interest in, understanding of and engagement with marine policy. This is in view of the fact that we are all users of the marine environment and therefore have a common interest in its sustainable use. Guest e ...
... anticipated that creating a more ocean literate society in Europe will result in increased interest in, understanding of and engagement with marine policy. This is in view of the fact that we are all users of the marine environment and therefore have a common interest in its sustainable use. Guest e ...
Campbell, I.H., Large Igneous Provinces and the mantle plume
... core and the mantle. High-pressure experimental studies of the melting point of iron–nickel alloys show that the core is several hundred degrees hotter than the overlying mantle. A temperature difference of this magnitude is expected to produce an unstable boundary layer above the core which, in tur ...
... core and the mantle. High-pressure experimental studies of the melting point of iron–nickel alloys show that the core is several hundred degrees hotter than the overlying mantle. A temperature difference of this magnitude is expected to produce an unstable boundary layer above the core which, in tur ...
Composition and degradation of organic matter in sediments from
... strong seasonality. Characteristic biomarkers for diatoms (brassicasterol) and dinoflagellates (dinosterol) were abundant in sediments off Peru and highly correlated to OM concentrations, indicating that these phytoplankton organisms, typically dominating in highly productive ...
... strong seasonality. Characteristic biomarkers for diatoms (brassicasterol) and dinoflagellates (dinosterol) were abundant in sediments off Peru and highly correlated to OM concentrations, indicating that these phytoplankton organisms, typically dominating in highly productive ...
Dehydration of serpentinized slab mantle: Seismic evidence from southwest Japan
... or thermal expansion (Hamaguchi et al., 1983) may be operating in the slab. However, these alone are not enough to explain the occurrence of such intermediate-depth events because the differential stresses are still too small compared with the high confining pressure. Therefore, some additional mech ...
... or thermal expansion (Hamaguchi et al., 1983) may be operating in the slab. However, these alone are not enough to explain the occurrence of such intermediate-depth events because the differential stresses are still too small compared with the high confining pressure. Therefore, some additional mech ...
Deep-Sea Research II - Max-Planck
... inhabit subsurface waters within the mixed layer at depthso50 m and exhibit diel vertical migration (Boehlert and Mundy, 1994; Lauth and Olson, 1996; Owen, 1997). Suboptimal physical conditions (e.g. low dissolved oxygen levels, low water temperatures) restrict the vertical and horizontal distributi ...
... inhabit subsurface waters within the mixed layer at depthso50 m and exhibit diel vertical migration (Boehlert and Mundy, 1994; Lauth and Olson, 1996; Owen, 1997). Suboptimal physical conditions (e.g. low dissolved oxygen levels, low water temperatures) restrict the vertical and horizontal distributi ...
Recycled crust in the Galápagos Plume source at 70 Ma
... Radiogenic isotope ratios of seven new Quepos samples (this study) were age corrected to initial eruptive values at 65 Ma using parent/daughter values reported in Table S1A. Additionally, we calculated the radiogenic composition of the Quepos and CLIP sources at 65 Ma and 90 Ma respectively by inver ...
... Radiogenic isotope ratios of seven new Quepos samples (this study) were age corrected to initial eruptive values at 65 Ma using parent/daughter values reported in Table S1A. Additionally, we calculated the radiogenic composition of the Quepos and CLIP sources at 65 Ma and 90 Ma respectively by inver ...
Isotope Composition of Organic Matter in Seawater
... their isotopic mass, natural abundance (%), and standard/reference materials for isotopic measurements. Similar to carbon, nitrogen, and sulfur, phosphorus is one of the important elements that build biochemical molecules. However, phosphorus has only one stable isotope (31P). Although phosphorus ha ...
... their isotopic mass, natural abundance (%), and standard/reference materials for isotopic measurements. Similar to carbon, nitrogen, and sulfur, phosphorus is one of the important elements that build biochemical molecules. However, phosphorus has only one stable isotope (31P). Although phosphorus ha ...
Earth and Planetary Science Letters Recycled crust in the
... Radiogenic isotope ratios of seven new Quepos samples (this study) were age corrected to initial eruptive values at 65 Ma using parent/daughter values reported in Table S1A. Additionally, we calculated the radiogenic composition of the Quepos and CLIP sources at 65 Ma and 90 Ma respectively by inver ...
... Radiogenic isotope ratios of seven new Quepos samples (this study) were age corrected to initial eruptive values at 65 Ma using parent/daughter values reported in Table S1A. Additionally, we calculated the radiogenic composition of the Quepos and CLIP sources at 65 Ma and 90 Ma respectively by inver ...
Review of the Lithium Isotope System as a Geochemical Tracer
... The mantle, as represented by fresh basalt (i.e., MORB, and Hawaiian basalt, the later being representative of OIB), appears to have average δ7Li values of about +3 to +5‰ (Fig. 1). The upper mantle is inferred to have a δ7Li equal to that of average MORB, ~ +4 ± 2‰ (Chan et al., 1992, 2002b; Tomasc ...
... The mantle, as represented by fresh basalt (i.e., MORB, and Hawaiian basalt, the later being representative of OIB), appears to have average δ7Li values of about +3 to +5‰ (Fig. 1). The upper mantle is inferred to have a δ7Li equal to that of average MORB, ~ +4 ± 2‰ (Chan et al., 1992, 2002b; Tomasc ...
The High Seas and Us
... poorly understood of all the Earth’s ecosystems. For example, an estimated 91% of marine species are still to be discovered (Mora et al., 2011). The enormity of the global ocean and the central role it plays in supporting life on Earth came sharply into focus more than 40 years ago when the Apollo m ...
... poorly understood of all the Earth’s ecosystems. For example, an estimated 91% of marine species are still to be discovered (Mora et al., 2011). The enormity of the global ocean and the central role it plays in supporting life on Earth came sharply into focus more than 40 years ago when the Apollo m ...
Chapter 1—Origins
... d. mapped the coasts of Australia and New Zealand e. All of the above are accomplishments of Captain James Cook. ANS: C ...
... d. mapped the coasts of Australia and New Zealand e. All of the above are accomplishments of Captain James Cook. ANS: C ...
Anoxic event
Oceanic anoxic events or anoxic events (Anoxia conditions) refer to intervals in the Earth's past where portions of oceans become depleted in oxygen (O2) at depths over a large geographic area. During some of these events, euxinia develops - euxinia refers to anoxic waters that contain H2S hydrogen sulfide. Although anoxic events have not happened for millions of years, the geological record shows that they happened many times in the past. Anoxic events coincide with several mass extinctions and may contribute to these events. These mass extinctions include some that geobiologists use as time markers in biostratigraphic dating. It is believed oceanic anoxic events are strongly linked to slowing of ocean circulation, climatic warming and elevated levels of greenhouse gases. Enhanced volcanism (through the release of CO2 and other greenhouse gases) is the proposed central external trigger for the development of these events.