![modern and ancient incompatible element-poor adakite](http://s1.studyres.com/store/data/002490064_1-c978b57ab760dc09ce7e6f4c786a79a8-300x300.png)
modern and ancient incompatible element-poor adakite
... km thick, are generally more evolved and have a more significant crustal component than those to south, where the crust is <40 km thick. The consequent along-arc variation in the thickness of the asthenospheric column below the arc, and thus the average extent of melting, might account for some of t ...
... km thick, are generally more evolved and have a more significant crustal component than those to south, where the crust is <40 km thick. The consequent along-arc variation in the thickness of the asthenospheric column below the arc, and thus the average extent of melting, might account for some of t ...
Tectonic History - Illinois State Geological Survey
... mountain ranges. Geological structures situated within plate interiors, far from the margins, are subject to reactivation during plate collisions. The far-field effects of the compressional stress commonly result in offsets along fault zones, uplift of basement rocks, and renewed subsidence of sedim ...
... mountain ranges. Geological structures situated within plate interiors, far from the margins, are subject to reactivation during plate collisions. The far-field effects of the compressional stress commonly result in offsets along fault zones, uplift of basement rocks, and renewed subsidence of sedim ...
Deforming Earth*s Crust
... This is Molokini Crater in Hawaii – it once stuck up above the water but it blew its top! ...
... This is Molokini Crater in Hawaii – it once stuck up above the water but it blew its top! ...
Theory of Plate Tectonics III
... Examples of an island arcs are the island chains of the western Pacific Ocean, such as Japan. In the case of Japan, volcanic islands are being created by the collision of the Pacific plate with the Eurasian plate. The Pacific plate being subducted beneath the Eurasian plate. ...
... Examples of an island arcs are the island chains of the western Pacific Ocean, such as Japan. In the case of Japan, volcanic islands are being created by the collision of the Pacific plate with the Eurasian plate. The Pacific plate being subducted beneath the Eurasian plate. ...
Crustal Deformation and Mountain Building - e
... subduct due to their relatively low density. The terranes are "peeled off" the subducted slab and thrust onto the leading edge of the continent. 38. The geography of central California preserves an accretionary wedge (Coast Ranges), a forearc basin (Great Valley), and the roots of a continental volc ...
... subduct due to their relatively low density. The terranes are "peeled off" the subducted slab and thrust onto the leading edge of the continent. 38. The geography of central California preserves an accretionary wedge (Coast Ranges), a forearc basin (Great Valley), and the roots of a continental volc ...
The NE-Atlantic system
... in Late Paleocene-Early Eocene by a significant volcanic event leading to the formation of the so-called “North Atlantic Large Igneous Province”. The averaged rate of magma extrusion was in the range of 1-2 cubic kilometres a year at that time. This transient magmatic episode has long-time been inte ...
... in Late Paleocene-Early Eocene by a significant volcanic event leading to the formation of the so-called “North Atlantic Large Igneous Province”. The averaged rate of magma extrusion was in the range of 1-2 cubic kilometres a year at that time. This transient magmatic episode has long-time been inte ...
geology-and-scenery-of-iceland-mikeadler
... “It provides a window into continent formation as it was early in Earth’s history because such continents are likely to have been produced by volcanism of a similar nature to that found in Iceland” ...
... “It provides a window into continent formation as it was early in Earth’s history because such continents are likely to have been produced by volcanism of a similar nature to that found in Iceland” ...
Volcanoes Stu Notes
... • Magma: a molten mixture of rock-forming substances, gases, and water from the mantle. • Lava: magma that reaches the surface, after it cools it forms solid rock. a. Volcanoes Plate Boundaries • 600 active volcanoes on land many more beneath the sea • Ring of Fire: a major volcanic belt formed by m ...
... • Magma: a molten mixture of rock-forming substances, gases, and water from the mantle. • Lava: magma that reaches the surface, after it cools it forms solid rock. a. Volcanoes Plate Boundaries • 600 active volcanoes on land many more beneath the sea • Ring of Fire: a major volcanic belt formed by m ...
Proterozoic Evolution of the Western Margin of the
... trend of the Great Falls tectonic zone (GFTZ). These data suggest that the basement in this area contains some accreted juvenile Paleoproterozoic arc-like terranes, possibly combined with a mafic underplate of similar age. This area largely underlies the Belt Basin and northern Idaho batholith and w ...
... trend of the Great Falls tectonic zone (GFTZ). These data suggest that the basement in this area contains some accreted juvenile Paleoproterozoic arc-like terranes, possibly combined with a mafic underplate of similar age. This area largely underlies the Belt Basin and northern Idaho batholith and w ...
Plate boundaries| sample answer
... in a process called folding. The uplifted land can be called fold mountains and an example is the Himalayas. Areas in which crust is created are called constructive plate boundaries. An example is a mid ocean ridge, deep under the ocean floor where land is created (Mid-Atlantic ridge has occurred du ...
... in a process called folding. The uplifted land can be called fold mountains and an example is the Himalayas. Areas in which crust is created are called constructive plate boundaries. An example is a mid ocean ridge, deep under the ocean floor where land is created (Mid-Atlantic ridge has occurred du ...
Notes-Stress, Faults and Folds
... Compression occurs when crustal rocks are squeezed together. Tension is the force that pulls rocks apart. Here rocks tend to become thinner. Shearing pushes rocks in opposite directions. Sheared rocks bend, twist or break. The results of stress are ______________ and _______________. When a rock has ...
... Compression occurs when crustal rocks are squeezed together. Tension is the force that pulls rocks apart. Here rocks tend to become thinner. Shearing pushes rocks in opposite directions. Sheared rocks bend, twist or break. The results of stress are ______________ and _______________. When a rock has ...
Ocean-Continent Convergent Plate Boundaries Quiz
... How is subduction important in the rock cycle? The oceanic crust brings rock back to the mantle when it collides and sinks under the continental crust and turn it back into magma. The magma may erupt through a volcano or cool beneath the surface turning the magma into igneous rock. ...
... How is subduction important in the rock cycle? The oceanic crust brings rock back to the mantle when it collides and sinks under the continental crust and turn it back into magma. The magma may erupt through a volcano or cool beneath the surface turning the magma into igneous rock. ...
File - tallisA2units
... The outpouring of material from the Earth’s crust produces a variety of landforms, the most significant of which are volcanoes and lava plateaux. Their global distribution is largely determined by the pattern of tectonic plates. Their impact on the landscape depends on a number of factors, including ...
... The outpouring of material from the Earth’s crust produces a variety of landforms, the most significant of which are volcanoes and lava plateaux. Their global distribution is largely determined by the pattern of tectonic plates. Their impact on the landscape depends on a number of factors, including ...
(43.5-46°S): Implications for Magma Genesis
... subduction and VLA, LA or HA volcanism in the SSVZ. With regard to the MEC magmas, there is also notable along-strike variability just in the short section between Puyuhuapi and Palena. Watt et al. (2014) outline a model of magma genesis for Palena group basalts which places them above a relatively ...
... subduction and VLA, LA or HA volcanism in the SSVZ. With regard to the MEC magmas, there is also notable along-strike variability just in the short section between Puyuhuapi and Palena. Watt et al. (2014) outline a model of magma genesis for Palena group basalts which places them above a relatively ...
Continental strike-slip faults - occur in every setting, on every scale
... - Sometimes, lateral offset of crusts of different thickness against each other can create steps in the crust-mantle boundary or in the lithospheric boundaries between two crustal blocks - stress concentrators - encourage mantle flow - Some areas on the southern San Andreas - where fault is transp ...
... - Sometimes, lateral offset of crusts of different thickness against each other can create steps in the crust-mantle boundary or in the lithospheric boundaries between two crustal blocks - stress concentrators - encourage mantle flow - Some areas on the southern San Andreas - where fault is transp ...
Lassen Volcanic National Park
... hand, the North American lithosphere is being pulled apart by Basin and Range extension. This extension began about 17 million years ago after the North American plate overrode a spreading center to the west and came into contact with the Pacific plate along the San Andreas fault (Atwater, 1970). Sh ...
... hand, the North American lithosphere is being pulled apart by Basin and Range extension. This extension began about 17 million years ago after the North American plate overrode a spreading center to the west and came into contact with the Pacific plate along the San Andreas fault (Atwater, 1970). Sh ...
3 The backdrop – a 70 million year old Plain
... The Monaro Volcanic Province is marked in blue on the map above. It is clear from the distribution of outliers of basalt, indicated by the scattered, patchy margin, that the province once covered a much larger area. The geological cause of these eruptions has yet to be clearly established, but their ...
... The Monaro Volcanic Province is marked in blue on the map above. It is clear from the distribution of outliers of basalt, indicated by the scattered, patchy margin, that the province once covered a much larger area. The geological cause of these eruptions has yet to be clearly established, but their ...
Plate Tectonics Activity
... Note** Earthquakes commonly occur along the length of the subducted slab and compressional structures (folds and faults) are often associated with the compressional zone near the colliding plates. The subducted lithosphere consists of relatively low-melting-point rocks (sediments and oceanic crust f ...
... Note** Earthquakes commonly occur along the length of the subducted slab and compressional structures (folds and faults) are often associated with the compressional zone near the colliding plates. The subducted lithosphere consists of relatively low-melting-point rocks (sediments and oceanic crust f ...
Structural controls on the emplacement of porphyry systems: the
... the opening and subsequent inversion of an intra-arc volcano-tectonic basin, the Abanico Basin. In the district the transition between syn-extension and syn-inversion volcanic rocks is marked by progressive unconformities formed around the Oligocene-Miocene boundary. Intrusive activity began in the ...
... the opening and subsequent inversion of an intra-arc volcano-tectonic basin, the Abanico Basin. In the district the transition between syn-extension and syn-inversion volcanic rocks is marked by progressive unconformities formed around the Oligocene-Miocene boundary. Intrusive activity began in the ...
Sedimentary Basins related to Volcanic Arcs
... lie behind the magmatic arc often the site of extension & thinning of crust may overlie either ocean or continental crust oceanic back-arc basins are eventually subducted and destroyed, or preserved in thrust complexes related to ocean closure. • back-arc basins on continental crust - more varied fa ...
... lie behind the magmatic arc often the site of extension & thinning of crust may overlie either ocean or continental crust oceanic back-arc basins are eventually subducted and destroyed, or preserved in thrust complexes related to ocean closure. • back-arc basins on continental crust - more varied fa ...
2003108 - Geological Society of America
... (as inferred from earthquakes by Pardo and Suárez, 1995) are included for reference. Approximate locations of Deep Sea Drilling Project legs 66 (L66), 67 (L67), and 84 (L84) are also indicated. Our geochemical database for the MVB (411 individual samples) concerns a wider area to the East and to the ...
... (as inferred from earthquakes by Pardo and Suárez, 1995) are included for reference. Approximate locations of Deep Sea Drilling Project legs 66 (L66), 67 (L67), and 84 (L84) are also indicated. Our geochemical database for the MVB (411 individual samples) concerns a wider area to the East and to the ...
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.