![The Plate Tectonic Model](http://s1.studyres.com/store/data/007338159_1-27f8aff848abfb374528e64b4c5f456d-300x300.png)
The Plate Tectonic Model
... Because the transform margins are simply a mechanism for managing differential spreading rates, they are always associated with spreading centers – that is, oceanic ridges. They cross the ridges at roughly right angles. They only occur in continental crust during the initial stages of continental r ...
... Because the transform margins are simply a mechanism for managing differential spreading rates, they are always associated with spreading centers – that is, oceanic ridges. They cross the ridges at roughly right angles. They only occur in continental crust during the initial stages of continental r ...
LITHOSPHERIC BUOYANCY - Lunar and Planetary Institute
... of mantle potential temperature. At younger or older ages the lithosphere is positively or negatively buoyant, respectively. The maximum age of zero net buoyancy is about 300 Myr for a mantle potential temperature of about 15000C corresponding to a crustal thickness of about 40 km. It must be regard ...
... of mantle potential temperature. At younger or older ages the lithosphere is positively or negatively buoyant, respectively. The maximum age of zero net buoyancy is about 300 Myr for a mantle potential temperature of about 15000C corresponding to a crustal thickness of about 40 km. It must be regard ...
A Digital Atlas of Terranes for the Northern Cordillera
... A Digital Atlas of Terranes for the Northern Cordillera Maurice Colpron (Yukon Geological Survey) and JoAnne Nelson (BC Geological Survey) December 2011 – Copyright © 2011 – YGS/BCGS The framework of the Cordilleran orogen of northwestern North America is commonly depicted as a ‘collage’ of terr ...
... A Digital Atlas of Terranes for the Northern Cordillera Maurice Colpron (Yukon Geological Survey) and JoAnne Nelson (BC Geological Survey) December 2011 – Copyright © 2011 – YGS/BCGS The framework of the Cordilleran orogen of northwestern North America is commonly depicted as a ‘collage’ of terr ...
Crust-Mantle Connections in the Kermadec Arc
... only in oceanic arcs; (2) the rate of continental crust accumulation, which is andesitic in composition, would have been greatest soon after subduction initiated on Earth, when most crust was thin; and (3) most andesite magmas erupted on continental crust could be recycled from “primary” andesite o ...
... only in oceanic arcs; (2) the rate of continental crust accumulation, which is andesitic in composition, would have been greatest soon after subduction initiated on Earth, when most crust was thin; and (3) most andesite magmas erupted on continental crust could be recycled from “primary” andesite o ...
A Digital Atlas of Terranes for the Northern Cordillera
... A Digital Atlas of Terranes for the Northern Cordillera Maurice Colpron (Yukon Geological Survey) and JoAnne Nelson (BC Geological Survey) December 2011 – Copyright © 2011 – YGS/BCGS The framework of the Cordilleran orogen of northwestern North America is commonly depicted as a ‘collage’ of terr ...
... A Digital Atlas of Terranes for the Northern Cordillera Maurice Colpron (Yukon Geological Survey) and JoAnne Nelson (BC Geological Survey) December 2011 – Copyright © 2011 – YGS/BCGS The framework of the Cordilleran orogen of northwestern North America is commonly depicted as a ‘collage’ of terr ...
d11 Transform-fault plate boundaries - e
... Faults with large horizontal displacement join between offset mid-oceanic ridge segments (Figure d11.1). Bathymetry shows that their fault trace continues on.2 The fault movement, as is revealed by earthquakes, is restricted to between the ridge segments (or to between a ridge and a trench if the fa ...
... Faults with large horizontal displacement join between offset mid-oceanic ridge segments (Figure d11.1). Bathymetry shows that their fault trace continues on.2 The fault movement, as is revealed by earthquakes, is restricted to between the ridge segments (or to between a ridge and a trench if the fa ...
The Geological and Tectonic Framework of Europe
... result of lithospheric plate interactions, which are now relatively well understood. The outer region of the Earth, or lithosphere, includes the crust and the upper mantle, and is a rheologically more rigid layer lying above a more plastic layer of the upper mantle, known as the asthenosphere. The l ...
... result of lithospheric plate interactions, which are now relatively well understood. The outer region of the Earth, or lithosphere, includes the crust and the upper mantle, and is a rheologically more rigid layer lying above a more plastic layer of the upper mantle, known as the asthenosphere. The l ...
1 Which of the following disasters would you most likely experience
... Which of the following disasters would you most likely experience in San Francisco? A) B) C) D) E) ...
... Which of the following disasters would you most likely experience in San Francisco? A) B) C) D) E) ...
Geological Society of America Bulletin
... The locus of andesitic volcanism in central Mexico extends in a west-east direction for more than 1,000 km, from the Pacific Coast to the margins of the High Mexican Plateau overlooking the Gulf of Mexico. Inspection of the Tectonic Map of Mexico (Fig. 1; de Cserna, 1961) reveals the complex nature ...
... The locus of andesitic volcanism in central Mexico extends in a west-east direction for more than 1,000 km, from the Pacific Coast to the margins of the High Mexican Plateau overlooking the Gulf of Mexico. Inspection of the Tectonic Map of Mexico (Fig. 1; de Cserna, 1961) reveals the complex nature ...
Volcanoes - MrDanielASBSukMSSci
... crust, which allows hot magma, volcanic ash and gases to escape from below the surface. •What is the difference between magma and lava? •Magma (from Greek μάγμα "paste") is a mixture of molten rock, volatiles and solids that is found beneath the surface of the Earth, and is expected to exist on othe ...
... crust, which allows hot magma, volcanic ash and gases to escape from below the surface. •What is the difference between magma and lava? •Magma (from Greek μάγμα "paste") is a mixture of molten rock, volatiles and solids that is found beneath the surface of the Earth, and is expected to exist on othe ...
Heterogeneous sources for Pleistocene lavas of Marie Byrd Land
... Mountains, resting depositionally upon frost-heaved periglacial surfaces and upon angular glacial boulders that mantle bedrock surfaces at low elevations. Many volcanic exposures consist of delicate tephra, cinder, and splatter forms, not evidently modified by wet-based glacial ice. In addition, a f ...
... Mountains, resting depositionally upon frost-heaved periglacial surfaces and upon angular glacial boulders that mantle bedrock surfaces at low elevations. Many volcanic exposures consist of delicate tephra, cinder, and splatter forms, not evidently modified by wet-based glacial ice. In addition, a f ...
In Sicily there are two active volcanoes: Mount Stromboli and Mount
... lithosphere (that is, the rigid outer stratum of the globe), which consists of basalt covered by mainly silicic sediments (which contain large quantities of water), and the resulting magmas have a high silica content because much of the melt is constituted by the sediments. Almost all volcanoes arou ...
... lithosphere (that is, the rigid outer stratum of the globe), which consists of basalt covered by mainly silicic sediments (which contain large quantities of water), and the resulting magmas have a high silica content because much of the melt is constituted by the sediments. Almost all volcanoes arou ...
The Early Mesozoic volcanic arc of western North America in
... at Sierra de Catorce and Charcas. In the latter area, andesitic lava flows contain a brecciated zone that, given the presence of autoclasts arranged in a ‘‘puzzle structure,’’ is interpreted as an autoclastic breccia and probable peperite, associated with a flow front or basal breccia that was apparen ...
... at Sierra de Catorce and Charcas. In the latter area, andesitic lava flows contain a brecciated zone that, given the presence of autoclasts arranged in a ‘‘puzzle structure,’’ is interpreted as an autoclastic breccia and probable peperite, associated with a flow front or basal breccia that was apparen ...
GEOL 1010 - Research at UVU
... 38. Briefly explain the concept of flood basalts, and give an example of some. 39. Name a batholith. What I mean is, right down the name of a batholith that someone else named. Where is the batholith you named, and about how big is it? (Now you can give it a name of your choosing, if you wish). 40. ...
... 38. Briefly explain the concept of flood basalts, and give an example of some. 39. Name a batholith. What I mean is, right down the name of a batholith that someone else named. Where is the batholith you named, and about how big is it? (Now you can give it a name of your choosing, if you wish). 40. ...
Afar - Do plumes exist?
... Red Sea and Gulf of Aden spreading: 30-15Ma stage one of rifting between Arabia and Africa creating the Red Sea. 10km rifting 20Ma Main period of extension. ...
... Red Sea and Gulf of Aden spreading: 30-15Ma stage one of rifting between Arabia and Africa creating the Red Sea. 10km rifting 20Ma Main period of extension. ...
Fore-arc basin
... Island arcs are of chains of volcanically active islands arranged in a curved arc An ocean trench occurs on the ocean-wards side Island arcs first develop on oceanic crust The crustal thickness in an arc is intermediate between oceanic and continental Volcanic activity begins abruptly at a Volcanic ...
... Island arcs are of chains of volcanically active islands arranged in a curved arc An ocean trench occurs on the ocean-wards side Island arcs first develop on oceanic crust The crustal thickness in an arc is intermediate between oceanic and continental Volcanic activity begins abruptly at a Volcanic ...
The role of lower continental crust and lithospheric mantle in the
... rocks cropping out in Sardinia (Italy) is presented here. These rocks are alkali basalts, hawaiites, basanites, tholeiitic basalts and basaltic andesites, and were divided into two groups with distinct isotopic compositions. The vast majority of lavas have relatively high 87 Sr/86 Sr (0.7043^0.7051) ...
... rocks cropping out in Sardinia (Italy) is presented here. These rocks are alkali basalts, hawaiites, basanites, tholeiitic basalts and basaltic andesites, and were divided into two groups with distinct isotopic compositions. The vast majority of lavas have relatively high 87 Sr/86 Sr (0.7043^0.7051) ...
New Geologic Mapping, Tahoe/Donner Region - Earth Science
... To investigate the relation of volcanic eruption centers to basement structure. To determine the geologic history of the area, including Tertiary volcanism and faulting. To complement the geologic data base of the greater Tahoe area. ...
... To investigate the relation of volcanic eruption centers to basement structure. To determine the geologic history of the area, including Tertiary volcanism and faulting. To complement the geologic data base of the greater Tahoe area. ...
Document
... by as much as a metre and sunk back by 1/3 of a metre. Thousands of small earthquakes are produced as earth surface moves. ...
... by as much as a metre and sunk back by 1/3 of a metre. Thousands of small earthquakes are produced as earth surface moves. ...
SO 2
... by as much as a metre and sunk back by 1/3 of a metre. Thousands of small earthquakes are produced as earth surface moves. ...
... by as much as a metre and sunk back by 1/3 of a metre. Thousands of small earthquakes are produced as earth surface moves. ...
Volcanoes
... Melting at mid-ocean ridges occurs because mantle is drawn upward to fill the gap left by diverging oceanic plates. Importantly, the rate of plate spreading is usually sufficiently high that the mantle beneath does not have time to cool by conduction as it rises. The resulting decrease in pressure a ...
... Melting at mid-ocean ridges occurs because mantle is drawn upward to fill the gap left by diverging oceanic plates. Importantly, the rate of plate spreading is usually sufficiently high that the mantle beneath does not have time to cool by conduction as it rises. The resulting decrease in pressure a ...
The Early Mesozoic volcanic arc of western North America in
... at Sierra de Catorce and Charcas. In the latter area, andesitic lava flows contain a brecciated zone that, given the presence of autoclasts arranged in a ‘‘puzzle structure,’’ is interpreted as an autoclastic breccia and probable peperite, associated with a flow front or basal breccia that was apparen ...
... at Sierra de Catorce and Charcas. In the latter area, andesitic lava flows contain a brecciated zone that, given the presence of autoclasts arranged in a ‘‘puzzle structure,’’ is interpreted as an autoclastic breccia and probable peperite, associated with a flow front or basal breccia that was apparen ...
Basin processes
... little volcanism. This finding has strong implications for estimation of stretching factor, which in the case of Baikal Rift Zone is around 1.7 but direct estimation gives a value of 1.3-1.4 if the magmatic addition is not taken into account. Similar differences may be expected for other rift zones, ...
... little volcanism. This finding has strong implications for estimation of stretching factor, which in the case of Baikal Rift Zone is around 1.7 but direct estimation gives a value of 1.3-1.4 if the magmatic addition is not taken into account. Similar differences may be expected for other rift zones, ...
Evaluating Volcanic Reservoirs
... of the Earth’s crust contains a volume of volcanic rock—formed by the ejection of lava at the surface—of 3.4 to 9 x 109 km3, an order of magnitude greater than the volume of sedimentary rock. This estimate includes extrusions at seafloor rift zones, where oceanic plates are pulling apart and new cru ...
... of the Earth’s crust contains a volume of volcanic rock—formed by the ejection of lava at the surface—of 3.4 to 9 x 109 km3, an order of magnitude greater than the volume of sedimentary rock. This estimate includes extrusions at seafloor rift zones, where oceanic plates are pulling apart and new cru ...
Definition of a Cenozoic alkaline magmatic
... combination of thin (<80 km) lithosphere underlain by metasomatized, mostly Pacific mantle at only slightly elevated temperatures. The age of the metasomatism is not known but may be related to a combination of Paleozoic-Mesozoic subduction along the Pacific margin of Gondwana and possible plume-rel ...
... combination of thin (<80 km) lithosphere underlain by metasomatized, mostly Pacific mantle at only slightly elevated temperatures. The age of the metasomatism is not known but may be related to a combination of Paleozoic-Mesozoic subduction along the Pacific margin of Gondwana and possible plume-rel ...
Northern Cordilleran Volcanic Province
![](https://commons.wikimedia.org/wiki/Special:FilePath/Mount_Edziza,_British_Columbia.jpg?width=300)
The Northern Cordilleran Volcanic Province (NCVP), formerly known as the Stikine Volcanic Belt, is a geologic province defined by the occurrence of Miocene to Holocene volcanoes in the Pacific Northwest of North America. This belt of volcanoes extends roughly north-northwest from northwestern British Columbia and the Alaska Panhandle through Yukon to the Southeast Fairbanks Census Area of far eastern Alaska, in a corridor hundreds of kilometres wide. It is the most recently defined volcanic province in the Western Cordillera. It has formed due to extensional cracking of the North American continent—similar to other on-land extensional volcanic zones, including the Basin and Range Province and the East African Rift. Although taking its name from the Western Cordillera, this term is a geologic grouping rather than a geographic one. The southmost part of the NCVP has more, and larger, volcanoes than does the rest of the NCVP; further north it is less clearly delineated, describing a large arch that sways westward through central Yukon.At least four large volcanoes are grouped with the Northern Cordilleran Volcanic Province, including Hoodoo Mountain in the Boundary Ranges, the Mount Edziza volcanic complex on the Tahltan Highland, and Level Mountain and Heart Peaks on the Nahlin Plateau. These four volcanoes have volumes of more than 15 km3 (3.6 cu mi), the largest and oldest which is Level Mountain with an area of 1,800 km2 (690 sq mi) and a volume of more than 860 km3 (210 cu mi). Apart from the large volcanoes, several smaller volcanoes exist throughout the Northern Cordilleran Volcanic Province, including cinder cones which are widespread throughout the volcanic zone. Most of these small cones have been sites of only one volcanic eruption; this is in contrast to the larger volcanoes throughout the volcanic zone, which have had more than one volcanic eruption throughout their history.The Northern Cordilleran Volcanic Province is part of an area of intensive earthquake and volcanic activity around the Pacific Ocean called the Pacific Ring of Fire. However, the Northern Cordilleran Volcanic Province is commonly interpreted to be part of a gap in the Pacific Ring of Fire between the Cascade Volcanic Arc further south and the Aleutian Arc further north. But the Northern Cordilleran Volcanic Province is recognized to include over 100 independent volcanoes that have been active in the past 1.8 million years. At least three of them have erupted in the past 360 years, making it the most active volcanic area in Canada. Nevertheless, the dispersed population within the volcanic zone has witnessed few eruptions due to remoteness and the infrequent volcanic activity.