Earthquakes Professor Jeffery Seitz Department of Earth
... The severity of an earthquake is expressed in terms of the intensity and magnitude. The intensity is based on the observed effects of the earthquake — it is an assessment of the damage caused by an earthquake at a specific location. Thus the intensity of an earthquake depends upon the strength of th ...
... The severity of an earthquake is expressed in terms of the intensity and magnitude. The intensity is based on the observed effects of the earthquake — it is an assessment of the damage caused by an earthquake at a specific location. Thus the intensity of an earthquake depends upon the strength of th ...
The lithosphere and asthenosphere of the
... 1-D models were calculated for the velocity of shear waves, polarized vertically (SV ) and horizontally (SH) from dispersed Rayleigh and Love surface waves. These had been recorded in Iceland by the ICEMELT broad-band seismic network, with about half of the waves coming from near-distance earthquake ...
... 1-D models were calculated for the velocity of shear waves, polarized vertically (SV ) and horizontally (SH) from dispersed Rayleigh and Love surface waves. These had been recorded in Iceland by the ICEMELT broad-band seismic network, with about half of the waves coming from near-distance earthquake ...
Geophysical-petrological model of the crust and upper mantle in the
... distribution of temperature, density, and mantle seismic velocities and the resulting surface heat flow, elevation, gravity, and geoid anomalies. LitMod-2D works under a forward modeling scheme; at each step, the model outputs (elevation, gravity and geoid anomalies, surface heat flow, and mantle seis ...
... distribution of temperature, density, and mantle seismic velocities and the resulting surface heat flow, elevation, gravity, and geoid anomalies. LitMod-2D works under a forward modeling scheme; at each step, the model outputs (elevation, gravity and geoid anomalies, surface heat flow, and mantle seis ...
The Indonesian Sedimentologists Forum (FOSI)
... initially during the northward subduction of the IndoAustralia Plate. The subsequent arc-continent collision between the passive margin of northern Australia and the Banda arc occurred from ca. 8 Ma onward (Charlton, 2000), however other researchers proposed a younger collision, probably in the Plio ...
... initially during the northward subduction of the IndoAustralia Plate. The subsequent arc-continent collision between the passive margin of northern Australia and the Banda arc occurred from ca. 8 Ma onward (Charlton, 2000), however other researchers proposed a younger collision, probably in the Plio ...
north american diamond deposits
... Of unique interest in some kimberlites are down-dropped blocks of country rocks. Emplacement processes involved in near-surface diadems and crater formation produced kimberlites containing numerous country rock fragments, some of which are the only preserved evidence for stratigraphic units that hav ...
... Of unique interest in some kimberlites are down-dropped blocks of country rocks. Emplacement processes involved in near-surface diadems and crater formation produced kimberlites containing numerous country rock fragments, some of which are the only preserved evidence for stratigraphic units that hav ...
Indentation of a continent with a built
... Morgan, 1968). Subduction zones are more or less asymmetric in profile. This is because subducting oceanic lithosphere is cold, dense and stiff compared to the leading edge of the non-subducting plate that accretes weak sediments in a cold hydraulic arc. More material is transferred across plate bou ...
... Morgan, 1968). Subduction zones are more or less asymmetric in profile. This is because subducting oceanic lithosphere is cold, dense and stiff compared to the leading edge of the non-subducting plate that accretes weak sediments in a cold hydraulic arc. More material is transferred across plate bou ...
© Terra Antartica Publication
... tectonic history of this sector of the Antarctic margin. The margin formed mainly in the Cretaceous, adjacent to the pre-breakup triple junction that developed between Greater India, Australia and Antarctica in the Jurassic and Cretaceous. The continental slope is dominated by the Bruce Rise, a mid- ...
... tectonic history of this sector of the Antarctic margin. The margin formed mainly in the Cretaceous, adjacent to the pre-breakup triple junction that developed between Greater India, Australia and Antarctica in the Jurassic and Cretaceous. The continental slope is dominated by the Bruce Rise, a mid- ...
Subduction tectonic erosion and Late Cretaceous subsidence along
... The clastic material of the UGS was derived only from source terrains to the south of the NCA. Due to continued exhumation and progressive erosional unroofing of Austroalpine basement complexes, metamorphic minerals such as chloritoid and, in younger parts of the sections, garnet and staurolite domi ...
... The clastic material of the UGS was derived only from source terrains to the south of the NCA. Due to continued exhumation and progressive erosional unroofing of Austroalpine basement complexes, metamorphic minerals such as chloritoid and, in younger parts of the sections, garnet and staurolite domi ...
Geodynamic Significance of the Kontum Massif in
... reported by Hutchison [1989] are estimates) and include K-Ar ages of 241–244 Ma from synkinematic biotites in a cordierite-sillimanite-biotite gneiss (Tran Ngoc Nam 1998), a 240-Ma 40Ar/39Ar age for a charnockite (Maluski and Lepvrier 1998; Maluski et al. 1999a), and U-Pb SHRIMP ages around 250 Ma f ...
... reported by Hutchison [1989] are estimates) and include K-Ar ages of 241–244 Ma from synkinematic biotites in a cordierite-sillimanite-biotite gneiss (Tran Ngoc Nam 1998), a 240-Ma 40Ar/39Ar age for a charnockite (Maluski and Lepvrier 1998; Maluski et al. 1999a), and U-Pb SHRIMP ages around 250 Ma f ...
The Petrogenetic Evolution of Lavas from Easter
... Intraplate volcanoes are widespread on Earth and make up large parts of the oceanic crust in many regions such as the East Pacific (Abers et al., 1988). Oceanic islands and seamounts have received much attention because their chemistry is not directly affected by contributions from continental mater ...
... Intraplate volcanoes are widespread on Earth and make up large parts of the oceanic crust in many regions such as the East Pacific (Abers et al., 1988). Oceanic islands and seamounts have received much attention because their chemistry is not directly affected by contributions from continental mater ...
Diversity in Nature
... deposits of clay, sand and gravel, normally very much younger than the bedrock. The diversity linked to these deposits shows very clearly through land use and settlement pattern, especially in rural communities. The geological processes that have formed these deposits in the Nordic countries are clo ...
... deposits of clay, sand and gravel, normally very much younger than the bedrock. The diversity linked to these deposits shows very clearly through land use and settlement pattern, especially in rural communities. The geological processes that have formed these deposits in the Nordic countries are clo ...
Post-Paleozoic activity
... communication, 1978). Accordingly, Carboniferous basins have not been reported from the Alleghanides, although marine faunas are reported (Thibaudeau, 1987) from coal-bearing beds of the Pictou Group in Nova Scotia, indicating that during the late Paleozoic some basins in the northern Appalachians s ...
... communication, 1978). Accordingly, Carboniferous basins have not been reported from the Alleghanides, although marine faunas are reported (Thibaudeau, 1987) from coal-bearing beds of the Pictou Group in Nova Scotia, indicating that during the late Paleozoic some basins in the northern Appalachians s ...
Geodynpub_files/Boutelier, Chemenda, 2011
... from a constitutive instability. The deformation bifurcation induced by this instability can occur even at positive hardening modulus (Rudnicki and Rice 1975; Chemenda 2007), i.e., during strengthening of the material (before reaching the stress peak on stressstrain diagrams) and especially when the ...
... from a constitutive instability. The deformation bifurcation induced by this instability can occur even at positive hardening modulus (Rudnicki and Rice 1975; Chemenda 2007), i.e., during strengthening of the material (before reaching the stress peak on stressstrain diagrams) and especially when the ...
Chromium isotope fractionation during subduction
... passed a critical threshold required for Cr(III) oxidation to Cr(VI), in a process likely linked to manganese redox cycling (Eary and Rai, 1987; Fendorf and Zasoski, 1992; Frei et al., 2009). The oxidized Cr(VI) is carried to the oceans as dissolved oxyanion species and eventually deposited in sedim ...
... passed a critical threshold required for Cr(III) oxidation to Cr(VI), in a process likely linked to manganese redox cycling (Eary and Rai, 1987; Fendorf and Zasoski, 1992; Frei et al., 2009). The oxidized Cr(VI) is carried to the oceans as dissolved oxyanion species and eventually deposited in sedim ...
Significance of angular unconformities between
... Tanjero Formation. Each of these unconformities is found in two different localities in the Zagros Imbricate Zone (i.e. the highly deformed zone immediately SW of the Zagros Suture) of the ZFTB of the Kurdistan Region near the border with Iran. The study uses recent geological mapping, structural an ...
... Tanjero Formation. Each of these unconformities is found in two different localities in the Zagros Imbricate Zone (i.e. the highly deformed zone immediately SW of the Zagros Suture) of the ZFTB of the Kurdistan Region near the border with Iran. The study uses recent geological mapping, structural an ...
Relocation Of Earthquakes Western Puerto Rico Region Using
... parameters around the continental root of North America by Fouch et al. (2000). The two oceanic islands have very different signatures. Results for SJG indicate a generally eastwest polarization and are consistent with the results of Russ et al. (1996). The polarization found for FDF differs dramati ...
... parameters around the continental root of North America by Fouch et al. (2000). The two oceanic islands have very different signatures. Results for SJG indicate a generally eastwest polarization and are consistent with the results of Russ et al. (1996). The polarization found for FDF differs dramati ...
Ghikas et al.IGR2010
... episodes of the break-up of Gondwana and evolved as latitudinal, east –west-oriented basins separated by discrete continental fragments. Most eastern Mediterranean ophiolites are spatially associated with both Triassic –Jurassic volcanic rocks and subophiolitic mélanges that rest tectonically on pa ...
... episodes of the break-up of Gondwana and evolved as latitudinal, east –west-oriented basins separated by discrete continental fragments. Most eastern Mediterranean ophiolites are spatially associated with both Triassic –Jurassic volcanic rocks and subophiolitic mélanges that rest tectonically on pa ...
Magmatic Evolution of the Eocene Volcanic Rocks of the Bijgerd
... However, Amidi et al., (1984) and Amidi and Michel (1985) suggest that the UromiehDokhtar zone was a linear rift basin, unrelated to subduction. The Neotethyean oceanic lithosphere started to subduct under Iranian subplate (part of the Euroasian plate) about Late Triassic, and continued through the ...
... However, Amidi et al., (1984) and Amidi and Michel (1985) suggest that the UromiehDokhtar zone was a linear rift basin, unrelated to subduction. The Neotethyean oceanic lithosphere started to subduct under Iranian subplate (part of the Euroasian plate) about Late Triassic, and continued through the ...
The Geological Heritage of Fingal
... However, due to lessons learnt in establishing the methodology, and because of urgent demands for information on sites from many quarters, a different approach has evolved. All Expert Panels have concluded their preliminary selection of candidate sites so that we now have a picture of the full range ...
... However, due to lessons learnt in establishing the methodology, and because of urgent demands for information on sites from many quarters, a different approach has evolved. All Expert Panels have concluded their preliminary selection of candidate sites so that we now have a picture of the full range ...
Full text PDF - Geochemical Perspectives
... crust, an observation later dramatically confirmed by the discovery of cosmogenic 10Be in subduction zone magmas. Because of this sediment, the flux into the mantle at subduction zones is more incompatible-element enriched than MORB. Although some fraction of this material is extracted into subducti ...
... crust, an observation later dramatically confirmed by the discovery of cosmogenic 10Be in subduction zone magmas. Because of this sediment, the flux into the mantle at subduction zones is more incompatible-element enriched than MORB. Although some fraction of this material is extracted into subducti ...
Overview of the Geology of Mount Shasta
... uniformly across Earth's surface. Instead, they are largely confined to narrow zones, like the circum-Pacific "Ring of Fire", that are the boundaries between the great lithospheric plates that cover the planet's surface (Figure 2). These rigid slabs of rock include the crust − thin seafloor basalts ...
... uniformly across Earth's surface. Instead, they are largely confined to narrow zones, like the circum-Pacific "Ring of Fire", that are the boundaries between the great lithospheric plates that cover the planet's surface (Figure 2). These rigid slabs of rock include the crust − thin seafloor basalts ...
File - Mr. Tugman`s Earth Science
... the correct units. Tell students that seafloor spreading occurs at an average rate of 5 cm per year. At this rate, how long would it take for a narrow sea that is 1 km wide to form? (about 20,000 years) Logical ...
... the correct units. Tell students that seafloor spreading occurs at an average rate of 5 cm per year. At this rate, how long would it take for a narrow sea that is 1 km wide to form? (about 20,000 years) Logical ...
Structure of the crust beneath Cameroon, West Africa, from the joint
... least-squares misfit comparable, a normalization of the data set is necessary, and this is done using the number of data points and variance for each of the data sets. An influence factor is used to control the trade-off between fitting the receiver functions and the group velocity curves. During th ...
... least-squares misfit comparable, a normalization of the data set is necessary, and this is done using the number of data points and variance for each of the data sets. An influence factor is used to control the trade-off between fitting the receiver functions and the group velocity curves. During th ...
Large igneous province
A large igneous province (LIP) is an extremely large accumulation of igneous rocks, including liquid rock (intrusive) or volcanic rock formations (extrusive), when hot magma extrudes from inside the Earth and flows out. The source of many or all LIPs is variously attributed to mantle plumes or to processes associated with plate tectonics. Types of LIPs can include large volcanic provinces (LVP), created through flood basalt and large plutonic provinces (LPP). Eleven distinct flood basalt episodes occurred in the past 250 million years, creating volcanic provinces, which coincided with mass extinctions in prehistoric times. Formation depends on a range of factors, such as continental configuration, latitude, volume, rate, duration of eruption, style and setting (continental vs. oceanic), the preexisting climate state, and the biota resilience to change.