Geology: Translation of terranes: Lessons from central Baja
... of strike-slip faults, their preservation potential in the cases of oblique convergence and oblique divergence is low. In the Sumatra case, the magmatic arc is likely to obliterate most faults. In the Gulf of California, transform faults and short spreading ridges have created small ocean basins, 2– ...
... of strike-slip faults, their preservation potential in the cases of oblique convergence and oblique divergence is low. In the Sumatra case, the magmatic arc is likely to obliterate most faults. In the Gulf of California, transform faults and short spreading ridges have created small ocean basins, 2– ...
Bresse Graben System, European Crust and Topo Europe
... this day. The rift flanks disinter the same types of rocks as the graben but there are no cretaceous, tertiary or quaternary formations because the rift flanks experienced erosion. Major zones with normal faults define the boundaries between the graben and the rift flanks. The URG consists of a Vari ...
... this day. The rift flanks disinter the same types of rocks as the graben but there are no cretaceous, tertiary or quaternary formations because the rift flanks experienced erosion. Major zones with normal faults define the boundaries between the graben and the rift flanks. The URG consists of a Vari ...
Petrogenesis of High Heat Producing Granite
... The A-type granite category was firstly defined by Loiselle and Wones (1979) to describe granites that have an alkaline composition, contain anhydrous minerals, crystallized under low oxygen fugacity and emplaced in intraplate or anorogenic settings. Since the introduction of the term A-type granite ...
... The A-type granite category was firstly defined by Loiselle and Wones (1979) to describe granites that have an alkaline composition, contain anhydrous minerals, crystallized under low oxygen fugacity and emplaced in intraplate or anorogenic settings. Since the introduction of the term A-type granite ...
GS-15
... folding event. Where seen, S2 is subparallel to S1. A microstructural analysis of F2 fold hinges in selected metasedimentary samples is currently being completed in order to determine the crosscutting relationships between S0, S1 and S2, and to analyze if a second foliation does indeed exist in many ...
... folding event. Where seen, S2 is subparallel to S1. A microstructural analysis of F2 fold hinges in selected metasedimentary samples is currently being completed in order to determine the crosscutting relationships between S0, S1 and S2, and to analyze if a second foliation does indeed exist in many ...
Lesson Objectives Vocabulary Introduction Causes of Earthquakes
... you learned in the Plate Tectonics chapter, scientists use the location of earthquakes to draw plate boundaries. The region around the Pacific Ocean is called the Pacific Ring of Fire. This is due to the volcanoes that line the region. The area also has the most earthquakes. About 80% of all earthqu ...
... you learned in the Plate Tectonics chapter, scientists use the location of earthquakes to draw plate boundaries. The region around the Pacific Ocean is called the Pacific Ring of Fire. This is due to the volcanoes that line the region. The area also has the most earthquakes. About 80% of all earthqu ...
Geology of Northern California Geolo
... thus influenced by two different kinds of boundaries between the North American and oceanic plates to the west: a transform boundary from Monterey Bay to Cape Mendocino and a remnant convergent boundary to the north. We will explore the consequences of these interactions in more detail in the sectio ...
... thus influenced by two different kinds of boundaries between the North American and oceanic plates to the west: a transform boundary from Monterey Bay to Cape Mendocino and a remnant convergent boundary to the north. We will explore the consequences of these interactions in more detail in the sectio ...
Seismic crustal structure between the Transylvanian
... In order to study the lithospheric structure in Romania a 450 km long WNW–ESE trending seismic refraction project was carried out in August/September 2001. It runs from the Transylvanian Basin across the East Carpathian Orogen and the Vrancea seismic region to the foreland areas with the very deep N ...
... In order to study the lithospheric structure in Romania a 450 km long WNW–ESE trending seismic refraction project was carried out in August/September 2001. It runs from the Transylvanian Basin across the East Carpathian Orogen and the Vrancea seismic region to the foreland areas with the very deep N ...
Field Trip Guide
... 1) Champlain Valley: Cambrian–Ordovician carbonate and clastic sedimentary rocks deposited on the eastern (present coordinates) continental margin of Laurentia (e.g., Stanley and Ratcliffe, 1985). This continent was left behind after the Rodinian supercontinent rifted apart during the Late Proteroz ...
... 1) Champlain Valley: Cambrian–Ordovician carbonate and clastic sedimentary rocks deposited on the eastern (present coordinates) continental margin of Laurentia (e.g., Stanley and Ratcliffe, 1985). This continent was left behind after the Rodinian supercontinent rifted apart during the Late Proteroz ...
Sedimentary Rocks
... deposited and the possible source rock, which may reveal areas subjected to erosion (see Section 2, this article); (2) physical, chemical, and/or biological processes effective during the deposition, and the depositional environments (Sections 3 and 4, this article); (3) deposition at the given plac ...
... deposited and the possible source rock, which may reveal areas subjected to erosion (see Section 2, this article); (2) physical, chemical, and/or biological processes effective during the deposition, and the depositional environments (Sections 3 and 4, this article); (3) deposition at the given plac ...
The asthenosphere low-velocity layer Over 100 years ago, Airy and
... concept of the asthenosphere as a relatively weak layer, in which graduai movements, subcrustal currents, movements to make isostasy possible, and movements of extended portions of Continental blocks relative to the main portion of the mantle may take place more easilv than in the lithosphere. More ...
... concept of the asthenosphere as a relatively weak layer, in which graduai movements, subcrustal currents, movements to make isostasy possible, and movements of extended portions of Continental blocks relative to the main portion of the mantle may take place more easilv than in the lithosphere. More ...
The East African Rift System: Does It Have Oil and Gas Potential?
... exposed flood basalts that preceded rifting. Areas unshaded or covered by flood basalts represent normal continental crust. As the crust is pulled apart you end up with thinned crust with a complex mixture of continental and volcanic rock. Eventually the crust thins to the point where oceanic-type b ...
... exposed flood basalts that preceded rifting. Areas unshaded or covered by flood basalts represent normal continental crust. As the crust is pulled apart you end up with thinned crust with a complex mixture of continental and volcanic rock. Eventually the crust thins to the point where oceanic-type b ...
Use of strontium isotope ratios and rare earth elements in apatite
... metabentonites from the Garntangen Member, Vik Forrnation, Oslo, Norway, and two sarnples from the Lower Visby Forrnation, Gotland, Sweden. The results for the Norwegian group show a bimodal distribution: a 'low' group (0.7041-{).7043) and a 'high' group (0.7061-{).7065). These groups correspond to ...
... metabentonites from the Garntangen Member, Vik Forrnation, Oslo, Norway, and two sarnples from the Lower Visby Forrnation, Gotland, Sweden. The results for the Norwegian group show a bimodal distribution: a 'low' group (0.7041-{).7043) and a 'high' group (0.7061-{).7065). These groups correspond to ...
Alternative global Cretaceous paleogeography
... (1976) showed that there are a number of marginal basins along ...
... (1976) showed that there are a number of marginal basins along ...
Evidence for Early Cretaceous oceanic crust trapped in the
... Ar/39 Ar dates. These new 40 Ar/39 Ar ages on two gabbro sites dredged in the Huatung Basin indicate the existence of Early Cretaceous oceanic crust east of Taiwan. The di¡erent amphibole age spectra are partially discordant, probably as a result of some hydrothermal alteration on the oceanic £oor. ...
... Ar/39 Ar dates. These new 40 Ar/39 Ar ages on two gabbro sites dredged in the Huatung Basin indicate the existence of Early Cretaceous oceanic crust east of Taiwan. The di¡erent amphibole age spectra are partially discordant, probably as a result of some hydrothermal alteration on the oceanic £oor. ...
Scandium
... O'Neill, 2014). The abundance of Sc in the Earth’s continental crust is higher, with average values of 31, 19, and 14 ppm for the lower, middle, and upper crust, respectively, and an average continental crust value of 21.9 ppm (Rudnick and Gao, 2014). It occurs in higher concentrations in oceanic cr ...
... O'Neill, 2014). The abundance of Sc in the Earth’s continental crust is higher, with average values of 31, 19, and 14 ppm for the lower, middle, and upper crust, respectively, and an average continental crust value of 21.9 ppm (Rudnick and Gao, 2014). It occurs in higher concentrations in oceanic cr ...
CatWardellThesis - University of Washington
... roughness. with many studies focusing upon features found only at specific spreading rates as well as those common to all spreading centers. An axial volcanic ridge forms during a magmatic phase where there is intrusion of magma to the surface of the crust; this builds up until intrusion rates decre ...
... roughness. with many studies focusing upon features found only at specific spreading rates as well as those common to all spreading centers. An axial volcanic ridge forms during a magmatic phase where there is intrusion of magma to the surface of the crust; this builds up until intrusion rates decre ...
No. 51. The Sveconorwegian Orogen of southern Scandinavia
... extensional) orogenic phases at between 1.14-0.96 Ga. Sveconorwegian orogenesis culminated in a continent-continent collision phase at 0.98-0.96 Ga that involved regional scale high-pressure granulite metamorphism and local emplacement of eclogites in the southeasternmost part of the orogen. The pri ...
... extensional) orogenic phases at between 1.14-0.96 Ga. Sveconorwegian orogenesis culminated in a continent-continent collision phase at 0.98-0.96 Ga that involved regional scale high-pressure granulite metamorphism and local emplacement of eclogites in the southeasternmost part of the orogen. The pri ...
The role of frictional strength on plate coupling at the subduction
... data from a wide range of rock types, showed that the static friction coefficient does not vary very much at pressures above 200 MPa, where it is on the order of 0.6 (f ≈ 30 ). However, Byerlee [1978] qualifies that observation with the important caveat that minerals populating fault gouges could h ...
... data from a wide range of rock types, showed that the static friction coefficient does not vary very much at pressures above 200 MPa, where it is on the order of 0.6 (f ≈ 30 ). However, Byerlee [1978] qualifies that observation with the important caveat that minerals populating fault gouges could h ...
The lithosphere and asthenosphere of the Iceland hotspot from
... 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 ...
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 ...
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.