Lasting mantle scars lead to perennial plate tectonics
... interiors are influenced by the depth of lithospheric heterogeneities, and that ML scars can guide deformation over other pre-existing features in the UC and LC. The range of deformation patterns exhibited from the models presented here indicates the complex nature of lithospheric heterogeneities and ...
... interiors are influenced by the depth of lithospheric heterogeneities, and that ML scars can guide deformation over other pre-existing features in the UC and LC. The range of deformation patterns exhibited from the models presented here indicates the complex nature of lithospheric heterogeneities and ...
A crustal model of the ultrahigh-pressure Dabie Shan orogenic belt
... for more than 2000 km and contains abundant high-pressure metamorphic rocks including abundant coesite-bearing eclogite and blueschist facies rocks [Liou et al., 1989]. UHP rocks crop out in the three easternmost ranges of the Qinling-Dabie orogen, in the Hong’an, Dabie, and Su-Lu areas (Figure 1). ...
... for more than 2000 km and contains abundant high-pressure metamorphic rocks including abundant coesite-bearing eclogite and blueschist facies rocks [Liou et al., 1989]. UHP rocks crop out in the three easternmost ranges of the Qinling-Dabie orogen, in the Hong’an, Dabie, and Su-Lu areas (Figure 1). ...
Roots of the Mariana Arc - Science
... Mariana Islands are the result of this volcanic activity, which frequently causes earthquakes as well. The movement of the Pacific Ocean tectonic plate has been likened to a huge conveyor belt on which new crust is formed at the oceanic spreading ridges off the western coasts of North and South Amer ...
... Mariana Islands are the result of this volcanic activity, which frequently causes earthquakes as well. The movement of the Pacific Ocean tectonic plate has been likened to a huge conveyor belt on which new crust is formed at the oceanic spreading ridges off the western coasts of North and South Amer ...
Do mantle plumes exist?
... and the continental lithosphere. Cordery et al (1997) pointed out that the solidus and liquidus of eclogite in the trapped slab is lower than mantle peridotite with eclogite being molten before peridotite. Hofmann and White (1982) deduced that ocean island basalt geochemistry is consistent with frac ...
... and the continental lithosphere. Cordery et al (1997) pointed out that the solidus and liquidus of eclogite in the trapped slab is lower than mantle peridotite with eclogite being molten before peridotite. Hofmann and White (1982) deduced that ocean island basalt geochemistry is consistent with frac ...
Basin and sub-basin crustal structure of a part of the western
... calculating the depth, size and shape of rock bodies that cause gravity anomalies, different hypothetical models/ bodies are to be tested. The parameters of these bodies are initially assumed e.g. density, depth, shape etc. Varying these parameters, the gravitational effects of these bodies are comp ...
... calculating the depth, size and shape of rock bodies that cause gravity anomalies, different hypothetical models/ bodies are to be tested. The parameters of these bodies are initially assumed e.g. density, depth, shape etc. Varying these parameters, the gravitational effects of these bodies are comp ...
The Emperor Seamounts: Southward Motion
... motion had occurred. There is also a general lack of circumPacific tectonic events (8) at this time. Recent age data suggest a somewhat older age for the bend [∼47 Ma (9)], but this revised timing still does not correspond to an episode of profound plate motion change recorded within the Pacific bas ...
... motion had occurred. There is also a general lack of circumPacific tectonic events (8) at this time. Recent age data suggest a somewhat older age for the bend [∼47 Ma (9)], but this revised timing still does not correspond to an episode of profound plate motion change recorded within the Pacific bas ...
Earthquakes and earthquake hazards
... •The middle compositional layer of Earth, between the core and the crust. •It is composed primarily of olivine and pyroxene. •Asthenosphere: mantle where weak, ductile rock is near melting but not molten. •Mesosphere: part of the mantle below the asthenosphere where rocks are stronger from ...
... •The middle compositional layer of Earth, between the core and the crust. •It is composed primarily of olivine and pyroxene. •Asthenosphere: mantle where weak, ductile rock is near melting but not molten. •Mesosphere: part of the mantle below the asthenosphere where rocks are stronger from ...
The 01/26/2001 Bhuj, India, Earthquake: Intraplate or Interplate?
... plate boundary is very irregular. This is true especially for the extruding Sulaiman lobe and range, which accommodate 5-14 mm yr-1 N-S plate convergence between the Indian and Eurasian plates [Bernard et al., 2000]. Using more realistic plate boundary geometries may predict more concentrated stress ...
... plate boundary is very irregular. This is true especially for the extruding Sulaiman lobe and range, which accommodate 5-14 mm yr-1 N-S plate convergence between the Indian and Eurasian plates [Bernard et al., 2000]. Using more realistic plate boundary geometries may predict more concentrated stress ...
Resolution of direction of oceanic magnetic lineations by the sixth
... line-leveled, data could be extended only up to a similar degree as a model from unfiltered data. Consequently, the recovery of genuine signal lost in filtering is difficult to implement. It was therefore decided to take the lower-degree coefficients from the (unfiltered) POMME-4 model and estimate ...
... line-leveled, data could be extended only up to a similar degree as a model from unfiltered data. Consequently, the recovery of genuine signal lost in filtering is difficult to implement. It was therefore decided to take the lower-degree coefficients from the (unfiltered) POMME-4 model and estimate ...
pdf preprint - Institute of Geophysics and Planetary Physics
... are extremely limited because of the nearly linear alignment of the islands (e.g., Wolfe et al., 2002). Such studies usually also do not have the resolution within the lithosphere and shallow asthenosphere to distinguish between the four models proposed for the swell uplift, but surface waves studie ...
... are extremely limited because of the nearly linear alignment of the islands (e.g., Wolfe et al., 2002). Such studies usually also do not have the resolution within the lithosphere and shallow asthenosphere to distinguish between the four models proposed for the swell uplift, but surface waves studie ...
Hydrated subducted crust at 100^250 km depth
... the slab, the e¡ect can then be treated as dispersion caused by a waveguide ^ subducted crust is a contiguous layer surrounded on each side by mantle. 2. Seismic dispersion We measure body wave dispersion for ¢ve subduction zones in the north Paci¢c, for events 100^ 250 km deep. At each subduction z ...
... the slab, the e¡ect can then be treated as dispersion caused by a waveguide ^ subducted crust is a contiguous layer surrounded on each side by mantle. 2. Seismic dispersion We measure body wave dispersion for ¢ve subduction zones in the north Paci¢c, for events 100^ 250 km deep. At each subduction z ...
Simulation of seismic waves at the earth`s crust (brittle–ductile
... Abstract. The earth’s crust presents two dissimilar rheological behaviors depending on the in situ stress-temperature conditions. The upper, cooler part is brittle, while deeper zones are ductile. Seismic waves may reveal the presence of the transition but a proper characterization is required. We f ...
... Abstract. The earth’s crust presents two dissimilar rheological behaviors depending on the in situ stress-temperature conditions. The upper, cooler part is brittle, while deeper zones are ductile. Seismic waves may reveal the presence of the transition but a proper characterization is required. We f ...
3D modelling of controlled-source electromagnetic fields in applied
... • Thomas Kalscheuer, Geophysics, Department of Earth Sciences, Uppsala University, [email protected]. • Maya Neytcheva, Sci. Computing, Department of Information Technology, Uppsala University, [email protected]. ...
... • Thomas Kalscheuer, Geophysics, Department of Earth Sciences, Uppsala University, [email protected]. • Maya Neytcheva, Sci. Computing, Department of Information Technology, Uppsala University, [email protected]. ...
Garces and Gee, 2007, Paleomageetic evidence of large footwall
... axis 010° for sites south of the fracture zone, and 000° for the northern sites. Sites 1271 and 1272, at the southern inside corner high, were excluded from further analysis because at this location deformation cannot be represented with a simple two-dimensional model and the rotational behavior is ...
... axis 010° for sites south of the fracture zone, and 000° for the northern sites. Sites 1271 and 1272, at the southern inside corner high, were excluded from further analysis because at this location deformation cannot be represented with a simple two-dimensional model and the rotational behavior is ...
imura0464 - IITB-Monash Research Academy
... episodes of continental amalgamation during supercontinent cycles. Mobile belts formed during these events have complex geometries and crustal architecture that may involve mixing of cratonic crust and accreted juvenile material caught up in the orogen/mobile belt. On the Precambrian Earth these mob ...
... episodes of continental amalgamation during supercontinent cycles. Mobile belts formed during these events have complex geometries and crustal architecture that may involve mixing of cratonic crust and accreted juvenile material caught up in the orogen/mobile belt. On the Precambrian Earth these mob ...
On the influence of the asthenospheric flow on the tectonics and
... the aim of quantitatively characterizing the overall deformation pattern or recognize additional potential contributions to the total strain. ...
... the aim of quantitatively characterizing the overall deformation pattern or recognize additional potential contributions to the total strain. ...
Introduction - Stanford Exploration Project
... (Appelbaum, 2002). The well penetrated stacked reservoir sands saturated with oil, ranging in overall column thickness from 400 to over 1,000ft. The quality of the oil from these zones is 35-45 degree API gravity, with very low sulphur content and preliminary data indicates the reservoirs contain se ...
... (Appelbaum, 2002). The well penetrated stacked reservoir sands saturated with oil, ranging in overall column thickness from 400 to over 1,000ft. The quality of the oil from these zones is 35-45 degree API gravity, with very low sulphur content and preliminary data indicates the reservoirs contain se ...
Seismic crustal structure between the Transylvanian
... Matenco et al., 2003) and a strong seismicity at intermediate depths, which is concentrated in the Vrancea area of the southeastern Carpathian bend (Fig. 1; Fuchs et al., 1979; Oncescu et al., 1998). While the shallow seismic activity scatters widely and has moderate magnitudes (Mw b 5.6), the epice ...
... Matenco et al., 2003) and a strong seismicity at intermediate depths, which is concentrated in the Vrancea area of the southeastern Carpathian bend (Fig. 1; Fuchs et al., 1979; Oncescu et al., 1998). While the shallow seismic activity scatters widely and has moderate magnitudes (Mw b 5.6), the epice ...
10. Crustal Structure of the Japan Trench: The Effect of Subduction
... Single sonobuoy refraction profiles were recorded at six stations (Figure 1). Profiles were shot unreversed along lines with minimal sea floor relief. A Bolt 1500Ctype air gun of 4.91 (300 cu. in.) capacity operated at a pressure of 80 to 90 kg/cm2 was used as the sound source. The velocity-depth in ...
... Single sonobuoy refraction profiles were recorded at six stations (Figure 1). Profiles were shot unreversed along lines with minimal sea floor relief. A Bolt 1500Ctype air gun of 4.91 (300 cu. in.) capacity operated at a pressure of 80 to 90 kg/cm2 was used as the sound source. The velocity-depth in ...
Earthquakes and the Earth`s Interior
... deformed slowly. Thus, when they are acted upon by differential stress, they tend to fracture. Faults Most natural earthquakes are caused by sudden slippage along a fault. Faults occur when brittle rocks fracture and there is displacement of one side of the fracture relative to the other side. The a ...
... deformed slowly. Thus, when they are acted upon by differential stress, they tend to fracture. Faults Most natural earthquakes are caused by sudden slippage along a fault. Faults occur when brittle rocks fracture and there is displacement of one side of the fracture relative to the other side. The a ...
A 100 m laser strainmeter system installed in a 1 km deep tunnel at
... near resonant frequencies ensures accurate determination of the FSR and thus of the absolute length of the cavity (Araya et al., 1999). With a modulation frequency of 12 MHz of the frequency-doubled Nd:YAG laser, the absolute cavity length can be determined with a resolving power of 0.1 m in a dist ...
... near resonant frequencies ensures accurate determination of the FSR and thus of the absolute length of the cavity (Araya et al., 1999). With a modulation frequency of 12 MHz of the frequency-doubled Nd:YAG laser, the absolute cavity length can be determined with a resolving power of 0.1 m in a dist ...
Structure of the crust beneath the southeastern Tibetan Plateau from
... against the stable Sichuan basin and South China block. Knowing the structure of the crust is a key to better understanding of crustal deformation and seismicity in this region. Here, we analyze recordings of teleseismic earthquakes from 25 temporary broadband seismic stations and one permanent stat ...
... against the stable Sichuan basin and South China block. Knowing the structure of the crust is a key to better understanding of crustal deformation and seismicity in this region. Here, we analyze recordings of teleseismic earthquakes from 25 temporary broadband seismic stations and one permanent stat ...
Earthscope
Earthscope is an earth science program using geological and geophysical techniques to explore the structure and evolution of the North American continent and to understand the processes controlling earthquakes and volcanoes. The project has three components: USARRAY, the Plate Boundary Observatory, and the San Andreas Fault Observatory at Depth.The project is funded by the National Science Foundation (NSF), and the data produced is publicly accessible in real-time. Organizations associated with the project include UNAVCO, the Incorporated Research Institutions for Seismology (IRIS), Stanford University, the United States Geological Survey (USGS) and National Aeronautics and Space Administration (NASA). Several international organizations also contribute to the initiative.