Reconstructing the Alps–Carpathians–Dinarides as a key to
... as a robust feature because their model is unique in incorporating a high-resolution 3D model of crustal velocities specific to the Alps. An important feature of all tomographic models so far is a narrow but distinct gap between the two +Vp anomalies at the junction of the Western-Central and Easter ...
... as a robust feature because their model is unique in incorporating a high-resolution 3D model of crustal velocities specific to the Alps. An important feature of all tomographic models so far is a narrow but distinct gap between the two +Vp anomalies at the junction of the Western-Central and Easter ...
A normalised seawater strontium isotope curve: possible
... 87 Sr/86 Sr ratio of RRS into the past is difficult because it depends not only on the isotopic evolution of the upper crust but also on the relative susceptibility to weathering, age and Sr content of the various silicate minerals that make up the exposed parts of the crust. The Sr isotopic evoluti ...
... 87 Sr/86 Sr ratio of RRS into the past is difficult because it depends not only on the isotopic evolution of the upper crust but also on the relative susceptibility to weathering, age and Sr content of the various silicate minerals that make up the exposed parts of the crust. The Sr isotopic evoluti ...
A combined study of melt inclusions and classical petrology on the
... Melt inclusions have been found in peritectic garnets of the investigated quartzofeldspathic migmatites. They are very small in size, mostly ≤ 10 µm, and typically show a well-developed negative crystal shape. Three types of inclusions were identified: totally crystallized (nanogranites), partially ...
... Melt inclusions have been found in peritectic garnets of the investigated quartzofeldspathic migmatites. They are very small in size, mostly ≤ 10 µm, and typically show a well-developed negative crystal shape. Three types of inclusions were identified: totally crystallized (nanogranites), partially ...
Oceanic corrugated surfaces and the strength of the axial
... specifically discuss the topography and the conditions of termination of oceanic corrugated surfaces. We then propose a conceptual model in which apparent variations of the rigidity of the axial plate during and after the formation of corrugated surfaces, are explained by variable degrees of mechanic ...
... specifically discuss the topography and the conditions of termination of oceanic corrugated surfaces. We then propose a conceptual model in which apparent variations of the rigidity of the axial plate during and after the formation of corrugated surfaces, are explained by variable degrees of mechanic ...
Transfer of melts in the sub-arc mantle: Insights from high
... peridotite could preserve pathways for melt transfer into the lower crust. The description of several features such as dykes, channels and magmatic intrusions in previous studies (Rodgers, 1973b; Paris, 1981; Prinzhofer et al., 1981 and references therein) gives good ground to start a detailed study ...
... peridotite could preserve pathways for melt transfer into the lower crust. The description of several features such as dykes, channels and magmatic intrusions in previous studies (Rodgers, 1973b; Paris, 1981; Prinzhofer et al., 1981 and references therein) gives good ground to start a detailed study ...
seismic activity, Yangtze River – Yellow Sea seismic belt, trend
... can be inferred from the global seismicity. Fig. 2 explains that when the Earth rotates faster, the activity of shallow earthquakes in North China-Northeast Plain usually decreases, while the seismicity in the regions of Liupan mountain-Qilian mountain-Altyn mountain increases, and vice versa. Thus, ...
... can be inferred from the global seismicity. Fig. 2 explains that when the Earth rotates faster, the activity of shallow earthquakes in North China-Northeast Plain usually decreases, while the seismicity in the regions of Liupan mountain-Qilian mountain-Altyn mountain increases, and vice versa. Thus, ...
To be submitted to either SDEE or BEE or SRL - EMCA-GEM
... (Nurmangambetov et al., 1999), respectively. The seismic hazard in Dushanbe is related to both shallow local earthquakes and deep focus distant earthquakes. For these reason, two different zoning maps were proposed for the town, one for building with less than 5 stories and the other for taller buil ...
... (Nurmangambetov et al., 1999), respectively. The seismic hazard in Dushanbe is related to both shallow local earthquakes and deep focus distant earthquakes. For these reason, two different zoning maps were proposed for the town, one for building with less than 5 stories and the other for taller buil ...
GIANT DIKE SWARMS: Earth, Venus, and Mars
... Figure 2 Histogram of size distribution of dike swarms on Earth, Venus, and Mars. Terrestrial data (n = 433) compiled from Ernst et al (1996). Venus radiating swarm data (n = 118)fromGrosfils & Head (1994a) and Grosfils (1996). Mars radiating swarm data (n = 8) from this review. Earth and Venus data ...
... Figure 2 Histogram of size distribution of dike swarms on Earth, Venus, and Mars. Terrestrial data (n = 433) compiled from Ernst et al (1996). Venus radiating swarm data (n = 118)fromGrosfils & Head (1994a) and Grosfils (1996). Mars radiating swarm data (n = 8) from this review. Earth and Venus data ...
Crustal structure of central and northern Iceland from analysis of
... partially molten sills in the lower crust. Less prominent low-velocity zones found in other regions of Iceland may arise from locally high temperatures in the crust or from acidic intrusive bodies at depth. A combination of the receiver function results and seismic refraction results constrains the ...
... partially molten sills in the lower crust. Less prominent low-velocity zones found in other regions of Iceland may arise from locally high temperatures in the crust or from acidic intrusive bodies at depth. A combination of the receiver function results and seismic refraction results constrains the ...
Earth`s first two billion years—The era of internally
... The magmatic and tectonic processes of the pre–2.5 Ga hot, young Earth differed profoundly from those of the modern planet. The ancient rocks differ strikingly in individual and collective composition, occurrence, association, and structure from modern rocks. Widespread forcing of Archean geology in ...
... The magmatic and tectonic processes of the pre–2.5 Ga hot, young Earth differed profoundly from those of the modern planet. The ancient rocks differ strikingly in individual and collective composition, occurrence, association, and structure from modern rocks. Widespread forcing of Archean geology in ...
Geophysical Journal International - E
... structure of the crust and lithospheric mantle. This was one of the motivations of the TopoIberia project (http://iberarray.ictja.csic.es/), a large-scale multidisciplinary research initiative to investigate the Earth’s structure and dynamics in Iberia and northern Morocco. In this work we analyse d ...
... structure of the crust and lithospheric mantle. This was one of the motivations of the TopoIberia project (http://iberarray.ictja.csic.es/), a large-scale multidisciplinary research initiative to investigate the Earth’s structure and dynamics in Iberia and northern Morocco. In this work we analyse d ...
Global tectonics - Scheme of work and lesson plan booklet
... (a) Describe and explain the nature of the asthenosphere as a rheid, plastic layer with 1 – 5% partial melting. Describe how this layer can be identified using P and S waves and its role in plate tectonics. ...
... (a) Describe and explain the nature of the asthenosphere as a rheid, plastic layer with 1 – 5% partial melting. Describe how this layer can be identified using P and S waves and its role in plate tectonics. ...
Early Paleozoic Tectonic and Thermomechanical
... widely, ranging from vertical extrusion of a coherent continental slab to channel flow of tectonically mixed mélange. To address this problem, we conducted integrated research across the North Qaidam UHP metamorphic belt using structural mapping, petrologic studies, and geochronologic and thermochro ...
... widely, ranging from vertical extrusion of a coherent continental slab to channel flow of tectonically mixed mélange. To address this problem, we conducted integrated research across the North Qaidam UHP metamorphic belt using structural mapping, petrologic studies, and geochronologic and thermochro ...
Chapter 4. TTG & Genesis of the Continental Crust
... grey diamond - TTG 3.0-3.5 Ga white diamond - TTG >3.5 Ga open circle - Archean sanukitoids ...
... grey diamond - TTG 3.0-3.5 Ga white diamond - TTG >3.5 Ga open circle - Archean sanukitoids ...
Christiansen, EH, and Keith, JD, 1996, Trace
... Imagining the physical conditions that would allow the instantaneous separation of each small fraction of melt is difficult. In most cases, a certain amount of melt must be generated before the source becomes permeably. Natural melting processes probably include aspects of batch and ...
... Imagining the physical conditions that would allow the instantaneous separation of each small fraction of melt is difficult. In most cases, a certain amount of melt must be generated before the source becomes permeably. Natural melting processes probably include aspects of batch and ...
Moho depths and Poisson`s ratios of Precambrian crust
... crustal thickness and Vp/Vs ratio under the station. In order to apply the H–k method, weights must be assigned to each phase in Eq. (1), and an average crustal Vp must be selected. A Vp of 6.5 km s 1, which is consistent with average crustal P wave velocities from previous studies of Precambrian ...
... crustal thickness and Vp/Vs ratio under the station. In order to apply the H–k method, weights must be assigned to each phase in Eq. (1), and an average crustal Vp must be selected. A Vp of 6.5 km s 1, which is consistent with average crustal P wave velocities from previous studies of Precambrian ...
What drives microplate motion and deformation in the northeastern
... (Figure 1), which separates the Caribbean plate from the North America plate, are diverse and complicated. The westward subduction of the North America plate at the northern Lesser Antilles changes to highly oblique subduction at the Puerto Rico Trench [Molnar and Sykes, 1969; Vening Meinesz et al., ...
... (Figure 1), which separates the Caribbean plate from the North America plate, are diverse and complicated. The westward subduction of the North America plate at the northern Lesser Antilles changes to highly oblique subduction at the Puerto Rico Trench [Molnar and Sykes, 1969; Vening Meinesz et al., ...
PDF
... bottom to top) from less to more HFSE-depleted and LILEenriched compositions and (a) generally comprise a lower, usually MORB/FAB unit and an upper VAB unit, sometimes along with boninites, both of which (b) form in a proto-forearc setting during subduction initiation (Fig. 2). An exception to this ...
... bottom to top) from less to more HFSE-depleted and LILEenriched compositions and (a) generally comprise a lower, usually MORB/FAB unit and an upper VAB unit, sometimes along with boninites, both of which (b) form in a proto-forearc setting during subduction initiation (Fig. 2). An exception to this ...
application of micro-seismic methods to geothermal exploration
... spreading is maximum on the master fault and rotation of faulted blocks result in tilted blocks. The central ring structures of Menengai and Olbanita calderas represent collapses associated with emptying of shallow magma chambers underlying them. Menengai-Olbanita area is located within a region tha ...
... spreading is maximum on the master fault and rotation of faulted blocks result in tilted blocks. The central ring structures of Menengai and Olbanita calderas represent collapses associated with emptying of shallow magma chambers underlying them. Menengai-Olbanita area is located within a region tha ...
29. Sulfur Isotope Ratios of Leg 126 Igneous Rocks
... igneous rocks in a transect across backarc and forearc basins and whether they bear in their δ 3 4 S values any of the igneous characteristics from the mantle source beneath the system. ...
... igneous rocks in a transect across backarc and forearc basins and whether they bear in their δ 3 4 S values any of the igneous characteristics from the mantle source beneath the system. ...
Seismic Refraction
... Seismic Methods: Refraction and Reflection Like the DC resistivity method, seismic methods, as typically applied in exploration seismology, are considered active geophysical methods. In seismic surveying, ground movement caused by some source* is measured at a variety of distances from the source. ...
... Seismic Methods: Refraction and Reflection Like the DC resistivity method, seismic methods, as typically applied in exploration seismology, are considered active geophysical methods. In seismic surveying, ground movement caused by some source* is measured at a variety of distances from the source. ...
Mantle plume
A mantle plume is a mechanism proposed in 1971 to explain volcanic regions of the earth that were not thought to be explicable by the then-new theory of plate tectonics. Some such volcanic regions lie far from tectonic plate boundaries, for example, Hawaii. Others represent unusually large-volume volcanism, whether on plate boundaries, e.g. Iceland, or basalt floods such as the Deccan or Siberian traps.A mantle plume is posited to exist where hot rock nucleates at the core-mantle boundary and rises through the Earth's mantle becoming a diapir in the Earth's crust. The currently active volcanic centers are known as ""hot spots"". In particular, the concept that mantle plumes are fixed relative to one another, and anchored at the core-mantle boundary, was thought to provide a natural explanation for the time-progressive chains of older volcanoes seen extending out from some such hot spots, such as the Hawaiian–Emperor seamount chain.The hypothesis of mantle plumes from depth is not universally accepted as explaining all such volcanism. It has required progressive hypothesis-elaboration leading to variant propositions such as mini-plumes and pulsing plumes. Another hypothesis for unusual volcanic regions is the ""Plate model"". This proposes shallower, passive leakage of magma from the mantle onto the Earth's surface where extension of the lithosphere permits it, attributing most volcanism to plate tectonic processes, with volcanoes far from plate boundaries resulting from intraplate extension.