Dynamic Topography and Long-Term Sea-Level Variations
... the changing pattern of downwelling mantle flow associated with plate subduction is a ...
... the changing pattern of downwelling mantle flow associated with plate subduction is a ...
Crust–mantle boundaries in the Taiwan–Luzon arc
... subducted underneath the Philippine Sea plate (Fig. 6 in Lallemand et al., 2001; Li et al., 2008). The estimated Philippine-Eurasia plate convergence velocity of 70–90 mm/yr in a northwest direction (305°, Seno, 1977; Yu et al., 1997) implies a minimum of 10 Ma of plate convergence, corroborating th ...
... subducted underneath the Philippine Sea plate (Fig. 6 in Lallemand et al., 2001; Li et al., 2008). The estimated Philippine-Eurasia plate convergence velocity of 70–90 mm/yr in a northwest direction (305°, Seno, 1977; Yu et al., 1997) implies a minimum of 10 Ma of plate convergence, corroborating th ...
Mantle-drip magmatism beneath the Altiplano
... Convective removal of continental lithospheric roots has been postulated to be the primary mechanism of recycling lithospheric mass into the asthenosphere under large plateaux such as the Altiplano-Puna in the central Andes. Convective instabilities are especially likely to develop where there is ex ...
... Convective removal of continental lithospheric roots has been postulated to be the primary mechanism of recycling lithospheric mass into the asthenosphere under large plateaux such as the Altiplano-Puna in the central Andes. Convective instabilities are especially likely to develop where there is ex ...
Arc Magmatic Tempos: Gathering the Evidence
... growth of oceanic and continental crust and the formation of an atmosphere. Along with the production of oceanic crust at mid-ocean ridges, one of the main results of such magmatism is the formation of long arcuate belts of volcanoes that overlie huge subsurface magmatic systems formed above subduct ...
... growth of oceanic and continental crust and the formation of an atmosphere. Along with the production of oceanic crust at mid-ocean ridges, one of the main results of such magmatism is the formation of long arcuate belts of volcanoes that overlie huge subsurface magmatic systems formed above subduct ...
Determination of fault friction from reactivation of
... structure and the subduction direction is dominantly perpendicular to the trench. We have excluded regions in which active or aseismic ridges or seamounts are subducting or there is a large component of oblique convergence, because the local stress state associated with these complexities may affect ...
... structure and the subduction direction is dominantly perpendicular to the trench. We have excluded regions in which active or aseismic ridges or seamounts are subducting or there is a large component of oblique convergence, because the local stress state associated with these complexities may affect ...
Southeast Asia`s changing palaeogeography
... thousands of islands spread across the equator in the area over 5 000 km wide between 95 °E and 140 °E (Fig. 1). To the south, west and east the region is surrounded by volcanic arcs where lithosphere of the Indian and Pacific Oceans is being subducted at high rates, accompanied by intense seismicity ...
... thousands of islands spread across the equator in the area over 5 000 km wide between 95 °E and 140 °E (Fig. 1). To the south, west and east the region is surrounded by volcanic arcs where lithosphere of the Indian and Pacific Oceans is being subducted at high rates, accompanied by intense seismicity ...
American Journal of Science - gemoc
... hydrosphere, such as shales. The increase in ␦18O after the end of the Archean may reflect the rapid growth and stabilization of cratons in the late Archean, which provided a framework for weathering and recycling of hydrated surface rocks into magma sources of granitoids after 2.5 Ga. Prior to the ...
... hydrosphere, such as shales. The increase in ␦18O after the end of the Archean may reflect the rapid growth and stabilization of cratons in the late Archean, which provided a framework for weathering and recycling of hydrated surface rocks into magma sources of granitoids after 2.5 Ga. Prior to the ...
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 ...
ch07 - earthjay science
... ideas: Continental Drift and Sea Floor Spreading. Plate Tectonic theory involves a number of large plates plus numerous small plates composed of crust and upper mantle (Lithosphere) that move slowly, change size, and shape. The Earth’s surface is a dynamic surface. © 2013 JOHN WILEY & SONS, INC. ALL ...
... ideas: Continental Drift and Sea Floor Spreading. Plate Tectonic theory involves a number of large plates plus numerous small plates composed of crust and upper mantle (Lithosphere) that move slowly, change size, and shape. The Earth’s surface is a dynamic surface. © 2013 JOHN WILEY & SONS, INC. ALL ...
Did Paleo-Tethyan anoxia kill arc magma fertility for
... associated epithermal Au ± Cu deposits (Fig. 1), but the majority of known deposits are Cretaceous to Cenozoic in age, and are related to subduction and closure of the Neo-Tethyan ocean basin (Aghazadeh et al., 2015; Richards, 2015b). Examples include the Majdanpek porphyry Cu-Mo-Au deposit in Serbi ...
... associated epithermal Au ± Cu deposits (Fig. 1), but the majority of known deposits are Cretaceous to Cenozoic in age, and are related to subduction and closure of the Neo-Tethyan ocean basin (Aghazadeh et al., 2015; Richards, 2015b). Examples include the Majdanpek porphyry Cu-Mo-Au deposit in Serbi ...
Endless Voyage 101 - Crafton Hills College
... 9. Describe how we obtain sediments from the ocean floor. (Include at least gravity cores, ...
... 9. Describe how we obtain sediments from the ocean floor. (Include at least gravity cores, ...
Ch02 Plate Tectonics
... distribution of earthquakes and volcanoes. Changes in past positions of continents and ocean basins. The origins of mountain belts and seamount chains. The origin and ages of ocean basins ...
... distribution of earthquakes and volcanoes. Changes in past positions of continents and ocean basins. The origins of mountain belts and seamount chains. The origin and ages of ocean basins ...
101 Questions and Answers Concerning
... Is not the resistance to subduction far too great to allow a plate to subduct? Are sediments, volcanoes, and plateaus actually scraped off subducting plates at trenches? Are sediments in trenches deformed and contorted as expected? How can plates possibly rift apart and move over underlying rock? Ho ...
... Is not the resistance to subduction far too great to allow a plate to subduct? Are sediments, volcanoes, and plateaus actually scraped off subducting plates at trenches? Are sediments in trenches deformed and contorted as expected? How can plates possibly rift apart and move over underlying rock? Ho ...
tectonic models for the geological evolution of crust, cratons and
... have been imbricated with mantle-derived oceanic rift rocks (La Flache and Camire, 1996), and in the BeardmoreGeraldton greenstone belt rocks from oceanic, arc and back-arc crusts have been delaminated and juxtaposed (Tomlinson et al. 1996). 5. The paper by Martin (1986) has had profound influence o ...
... have been imbricated with mantle-derived oceanic rift rocks (La Flache and Camire, 1996), and in the BeardmoreGeraldton greenstone belt rocks from oceanic, arc and back-arc crusts have been delaminated and juxtaposed (Tomlinson et al. 1996). 5. The paper by Martin (1986) has had profound influence o ...
plate puzzle - Purdue University
... their differing interpretations. After a brief time for discussion, ask a few students to explain what their plate’s motion is and how it is interacting with adjacent plates. 4. Find locations on the map that are associated with (Descriptions and illustrations of these plate boundaries are included ...
... their differing interpretations. After a brief time for discussion, ask a few students to explain what their plate’s motion is and how it is interacting with adjacent plates. 4. Find locations on the map that are associated with (Descriptions and illustrations of these plate boundaries are included ...
Dynamic topography and long-term sea-level variations
... induced) topography change over the last 30 Myr. We also show that the changing pattern of downwelling mantle flow associated with plate subduction is a significant contributor to the background eustatic sea-level trend, which is also of order 100 m during the 30 Myr time window. Therefore, Late-Cenoz ...
... induced) topography change over the last 30 Myr. We also show that the changing pattern of downwelling mantle flow associated with plate subduction is a significant contributor to the background eustatic sea-level trend, which is also of order 100 m during the 30 Myr time window. Therefore, Late-Cenoz ...
Polarized plate tectonics
... function of the relevant active tectonic, initial geometry of involved plates and their kind: oceanic, continental or transitional. Rifts As in the case of accretionary prisms, within rifts three different kinds can be identified. The linear rift (Atlantic, E-Africa) requires that the lithosphere on ...
... function of the relevant active tectonic, initial geometry of involved plates and their kind: oceanic, continental or transitional. Rifts As in the case of accretionary prisms, within rifts three different kinds can be identified. The linear rift (Atlantic, E-Africa) requires that the lithosphere on ...
On subducting slab entrainment of buoyant asthenosphere
... the Basin and Range (Goes and van der Lee, 2002) in the western U.S. However, beneath stable continental regions such as the Archaean shields in W. Australia (Gaherty et al., 1999) and N. America (Goes and van der Lee, 2002) seismic wavespeeds are significantly faster, implying the presence of much s ...
... the Basin and Range (Goes and van der Lee, 2002) in the western U.S. However, beneath stable continental regions such as the Archaean shields in W. Australia (Gaherty et al., 1999) and N. America (Goes and van der Lee, 2002) seismic wavespeeds are significantly faster, implying the presence of much s ...
The Hindu Kush Seismic Zone as a Paradigm
... high-pressure clinoenstatite formed at depths 1250 km (Bozhilov et al. 1999). These deep, mantle-born garnet peridotites are a tantalizing suggestion that continental crust may be subducted to a 1185–250km depth, although it is equally plausible that such garnet peridotites were transported upward b ...
... high-pressure clinoenstatite formed at depths 1250 km (Bozhilov et al. 1999). These deep, mantle-born garnet peridotites are a tantalizing suggestion that continental crust may be subducted to a 1185–250km depth, although it is equally plausible that such garnet peridotites were transported upward b ...
7.08 Mantle Downwellings and the Fate of Subducting Slabs
... with descending plate material beneath trenches (cf. Isacks et al., 1968). In addition, it was recognized that earthquake focal mechanisms of the deepest earthquakes are aligned with the axis of compression along the dip of the plane delineated by the hypocenters (cf. Isacks and Molnar, 1971; see Ch ...
... with descending plate material beneath trenches (cf. Isacks et al., 1968). In addition, it was recognized that earthquake focal mechanisms of the deepest earthquakes are aligned with the axis of compression along the dip of the plane delineated by the hypocenters (cf. Isacks and Molnar, 1971; see Ch ...
Global tectonic significance of the Solomon
... for significantly higher rates of continental growth than growth only by accretion of island arcs. The Ontong Java Plateau (OJP) of the southwestern Pacific Ocean is the largest and thickest oceanic plateau on Earth and the largest plateau currently converging on an island arc (Solomon Islands). For ...
... for significantly higher rates of continental growth than growth only by accretion of island arcs. The Ontong Java Plateau (OJP) of the southwestern Pacific Ocean is the largest and thickest oceanic plateau on Earth and the largest plateau currently converging on an island arc (Solomon Islands). For ...
Hydrocarbon basins in SE Asia: understanding why they are there
... The Mesozoic sedimentary record is very limited but suggests that much of Sundaland was emergent. Barber et al. (2005) suggested a complex shuffling of Cathaysian and Gondwana blocks during the Late Palaeozoic and Early Mesozoic, possibly associated with important strike-slip faulting. During the Me ...
... The Mesozoic sedimentary record is very limited but suggests that much of Sundaland was emergent. Barber et al. (2005) suggested a complex shuffling of Cathaysian and Gondwana blocks during the Late Palaeozoic and Early Mesozoic, possibly associated with important strike-slip faulting. During the Me ...
Cratons, mobile belts, alkaline rocks and
... material of various compositions (Jordan 1981; McDonough 1990). In both hypotheses (one does not exclude the other), the continental lithospheric mantle thickening (cratonization) process takes time. Construction of diagram (B) is based on a maximum strength for crust of 400 MPa at 400 °C and for co ...
... material of various compositions (Jordan 1981; McDonough 1990). In both hypotheses (one does not exclude the other), the continental lithospheric mantle thickening (cratonization) process takes time. Construction of diagram (B) is based on a maximum strength for crust of 400 MPa at 400 °C and for co ...
The westward drift of the lithosphere
... Assuming an active pull from only that part of a slab between depths of 50 km and 350 km, and considering for example the Marianas slab, the following concerns can be envisaged. The negative buoyancy of an ~300-km-long slab should be able to pull the 10,000-km-long Pacific plate, overcoming the fric ...
... Assuming an active pull from only that part of a slab between depths of 50 km and 350 km, and considering for example the Marianas slab, the following concerns can be envisaged. The negative buoyancy of an ~300-km-long slab should be able to pull the 10,000-km-long Pacific plate, overcoming the fric ...
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.