Activity–Pacific Northwest Tectonic Block Model
... of coastal blocks with respect to stable North America (yellow arrows). The southern Cascade volcanic arc (red triangles) erupts along the trailing edge of Oregon block in a region of crustal extension. Orange areas, representing young volcanic rocks erupted in the last 2 million years, are more vol ...
... of coastal blocks with respect to stable North America (yellow arrows). The southern Cascade volcanic arc (red triangles) erupts along the trailing edge of Oregon block in a region of crustal extension. Orange areas, representing young volcanic rocks erupted in the last 2 million years, are more vol ...
Evolution of magma-poor continental margins from rifting to sea¯oor
... blocks lie 10±20 km apart over continental crust 20±30 km thick. Oceanward, wherever crustal blocks are &7 km thick, such faults are clearly listric (downward-¯attening and concave upward), even penetrating the mantle, and closer together; the crust tapers oceanward to zero thickness within a distan ...
... blocks lie 10±20 km apart over continental crust 20±30 km thick. Oceanward, wherever crustal blocks are &7 km thick, such faults are clearly listric (downward-¯attening and concave upward), even penetrating the mantle, and closer together; the crust tapers oceanward to zero thickness within a distan ...
Field guide
... Keller and Cather (1994a). These studies addressed the structure, stratigraphy, and tectonic setting of individual basins spanning almost the entire length of the rift. Structural models of rifting presented in GSA Special Paper 291 have guided exploration for and management of natural resources and ...
... Keller and Cather (1994a). These studies addressed the structure, stratigraphy, and tectonic setting of individual basins spanning almost the entire length of the rift. Structural models of rifting presented in GSA Special Paper 291 have guided exploration for and management of natural resources and ...
occurrence of the ocean and its evolution toward an
... an island arc volcanism associated with base metal mineralizations and the deposition of arc sedimentary formations. In some special conditions a regional metamorphism and rarely a load metamorphism could manifest themselves. The subduction process is of two types: the Andeantype and the Mariana-typ ...
... an island arc volcanism associated with base metal mineralizations and the deposition of arc sedimentary formations. In some special conditions a regional metamorphism and rarely a load metamorphism could manifest themselves. The subduction process is of two types: the Andeantype and the Mariana-typ ...
Southwest U.S. Region Mountain
... Its subduction built most of the North American Cordillera, bunching up the west end of the North American plate like folds It is also the origin of the Sierra Nevada Batholith via subduction under North America ...
... Its subduction built most of the North American Cordillera, bunching up the west end of the North American plate like folds It is also the origin of the Sierra Nevada Batholith via subduction under North America ...
`lhe Martin Group in the Greater Beaverlodge Area by F. F. Langford
... the siltstone may have buff-yellow bleached spots and zones. Bright pink sandstone and a few thin conglonerate beds like those of the Seaplane Base Formation are intercalated with the argillites, particularly towards the base. Typical rocks of this formation are exposed in the large road cut south o ...
... the siltstone may have buff-yellow bleached spots and zones. Bright pink sandstone and a few thin conglonerate beds like those of the Seaplane Base Formation are intercalated with the argillites, particularly towards the base. Typical rocks of this formation are exposed in the large road cut south o ...
Idaho Geology Virtual Field Trip
... Batholith formed during late Cretaceous compression event. At this time, the dense oceanic Farallon Plate was subducted beneath the more buoyant continental North American Plate. The oceanic crust was subducted into the lithosphere until heat, pressure, and slab dewatering initiated melting of the o ...
... Batholith formed during late Cretaceous compression event. At this time, the dense oceanic Farallon Plate was subducted beneath the more buoyant continental North American Plate. The oceanic crust was subducted into the lithosphere until heat, pressure, and slab dewatering initiated melting of the o ...
Unit F791 - Global tectonics
... movement on reverse faults OR movement on thrusts OR movement on faults caused by compression OR collision of Indian and Eurasian plates ...
... movement on reverse faults OR movement on thrusts OR movement on faults caused by compression OR collision of Indian and Eurasian plates ...
Density of Oceanic Crust
... Certain properties of a substance are both distinctive and relatively easy to determine. Density, the ratio between a sample’s mass and volume at a specific temperature and pressure (like standard ambient temperature and pressure), is one such property. Regardless of the size of a sample, the densit ...
... Certain properties of a substance are both distinctive and relatively easy to determine. Density, the ratio between a sample’s mass and volume at a specific temperature and pressure (like standard ambient temperature and pressure), is one such property. Regardless of the size of a sample, the densit ...
Passive Continental Margin Around East Coast India
... remarkable suites of arcuate reflectors, dipping seaward to form a wedge-shaped structure. Their general characteristics and velocity structure suggest that they may be largely volcanic in nature, but there is no agreed upon model for their origin. Nevertheless it is generally thought that they lie ...
... remarkable suites of arcuate reflectors, dipping seaward to form a wedge-shaped structure. Their general characteristics and velocity structure suggest that they may be largely volcanic in nature, but there is no agreed upon model for their origin. Nevertheless it is generally thought that they lie ...
geology of the eureka peak and spanish lake map areas, british
... and assigns the Mesozoic metasedimentary and volcanic sequences to the Nicola group. The present geological configuration of the Quesnel Lake area is believed to be a result of a Jurassic convergent event during which the allochthonous assemblages of the Quesnel Terrane were thrust eastwards over th ...
... and assigns the Mesozoic metasedimentary and volcanic sequences to the Nicola group. The present geological configuration of the Quesnel Lake area is believed to be a result of a Jurassic convergent event during which the allochthonous assemblages of the Quesnel Terrane were thrust eastwards over th ...
Arc Magmatism
... • Activity along arcuate volcanic island chains along subduction zones • Distinctly different from the mainly basaltic provinces – Composition more diverse and silicic – Basalt generally occurs in subordinate quantities – More explosive than the quiescent basalts – Strato-volcanoes are the most comm ...
... • Activity along arcuate volcanic island chains along subduction zones • Distinctly different from the mainly basaltic provinces – Composition more diverse and silicic – Basalt generally occurs in subordinate quantities – More explosive than the quiescent basalts – Strato-volcanoes are the most comm ...
pegmatites and pegmatites, just like granites and granites
... there to lump! To many, the formation of a granitic magma is strictly synonymous with subduction of crust or overthickening of crust owing to collision of continental plates. The magmas are calc-alkaline in character, and the plutonic and volcanic rocks are metaluminous to peraluminous, depending on ...
... there to lump! To many, the formation of a granitic magma is strictly synonymous with subduction of crust or overthickening of crust owing to collision of continental plates. The magmas are calc-alkaline in character, and the plutonic and volcanic rocks are metaluminous to peraluminous, depending on ...
old exam questions
... 37. Refer to slide. Which mountain is more likely to have a slope failure if conditions are right? a. the one on the right c. both are equally likely b. the one on the left d. neither is likely to fail 38. Vegetation is an important stabilizer to prevent or slow the effects of a. wind erosion d. all ...
... 37. Refer to slide. Which mountain is more likely to have a slope failure if conditions are right? a. the one on the right c. both are equally likely b. the one on the left d. neither is likely to fail 38. Vegetation is an important stabilizer to prevent or slow the effects of a. wind erosion d. all ...
Late Cenozoic denudation and uplift rates in the Santa Lucia
... studied area. Rapid bedrock uplift may be accommodated by oblique slip on high-angle transform faults within the oblique San Andreas system (Spotila et al., 2001). In this case, the episode of bedrock uplift that we deduce between ca. 6 and 2 Ma may be a direct result of the local plate-boundary geo ...
... studied area. Rapid bedrock uplift may be accommodated by oblique slip on high-angle transform faults within the oblique San Andreas system (Spotila et al., 2001). In this case, the episode of bedrock uplift that we deduce between ca. 6 and 2 Ma may be a direct result of the local plate-boundary geo ...
Uranium-lead geochronology of two intrusions in the southern
... (Fig. 1). Several smaller bodies are found in high country to the south, north of Cedar River. The Mount Priestly stock intrudes sedimentary strata of the Bowser Lake Group. Extensive stockworks of dykes and pyritized sedimentary strata characterize the intrusion margin locally. The most common rock ...
... (Fig. 1). Several smaller bodies are found in high country to the south, north of Cedar River. The Mount Priestly stock intrudes sedimentary strata of the Bowser Lake Group. Extensive stockworks of dykes and pyritized sedimentary strata characterize the intrusion margin locally. The most common rock ...
Pages 107-112
... and youngest region of the field which is called Al Haruj al Aswad. The extensive lava plateaus cover an area of at least 16,000 km2 in Al Haruj al Aswad, preserved in variable eroded aa lava fields and subordinate pahoehoe lava flows (Busrewil and Suwesi 1993). The entire Al Haruj totals 45,000 km2 ...
... and youngest region of the field which is called Al Haruj al Aswad. The extensive lava plateaus cover an area of at least 16,000 km2 in Al Haruj al Aswad, preserved in variable eroded aa lava fields and subordinate pahoehoe lava flows (Busrewil and Suwesi 1993). The entire Al Haruj totals 45,000 km2 ...
witts_etal_2011 Barito Basin Kalimantan_IPA
... The Barito Basin is located in southeast Kalimantan, Borneo. The basin contains a thick succession of sedimentary rocks that are well exposed along the eastern margin of the basin (Fig. 1). The basin is bound to the west by the Schwaner Complex, comprising poorly dated regionally and contact metamor ...
... The Barito Basin is located in southeast Kalimantan, Borneo. The basin contains a thick succession of sedimentary rocks that are well exposed along the eastern margin of the basin (Fig. 1). The basin is bound to the west by the Schwaner Complex, comprising poorly dated regionally and contact metamor ...
composition of biotite from granitic rocks
... spatial, genetic and chemical characteristics (Fig. 1) (Clarke et al. 1997); 1) the central plutons, slightly younger (372 Ma) and composed of strongly peraluminous garnet-, cordierite- and even andalusite-bearing monzogranite or granodiorite and, 2) the peripheral plutons, slightly older (378 Ma) a ...
... spatial, genetic and chemical characteristics (Fig. 1) (Clarke et al. 1997); 1) the central plutons, slightly younger (372 Ma) and composed of strongly peraluminous garnet-, cordierite- and even andalusite-bearing monzogranite or granodiorite and, 2) the peripheral plutons, slightly older (378 Ma) a ...
Study Questions for Quiz #2
... A) post cooling history. B) texture. C) chemical composition. D) structural deformation. E) cooling history. Answer: C 12) The largest volcanoes on the Earth are A) composite volcanoes. B) cinder cones. C) spatter cones. D) stratovolcanoes. E) shield volcanoes. Answer: E 13) Which of the following i ...
... A) post cooling history. B) texture. C) chemical composition. D) structural deformation. E) cooling history. Answer: C 12) The largest volcanoes on the Earth are A) composite volcanoes. B) cinder cones. C) spatter cones. D) stratovolcanoes. E) shield volcanoes. Answer: E 13) Which of the following i ...
PDF
... by elevated abundances of immobile incompatible trace elements (Fig. 4A), the most incompatible of which are one to two orders of magnitude enriched relative to normal midoceanic ridge basalt (N-MORB). This implies that the alkalic mafic magma was derived from extremely low degree of partial melts ( ...
... by elevated abundances of immobile incompatible trace elements (Fig. 4A), the most incompatible of which are one to two orders of magnitude enriched relative to normal midoceanic ridge basalt (N-MORB). This implies that the alkalic mafic magma was derived from extremely low degree of partial melts ( ...
Volcanism of the Palaeoproterozoic Bushveld Large Igneous Province: the Rooiberg
... geochronologic data, the temporal span of the Rooiberg Group is poorly understood. The Rooiberg Group consists of basaltic to rhyolitic lava erupted from fissural volcanism with estimated eruption temperatures of the rhyolitic lavas exceeding 1000°C. Minor explosive eruptions are represented by pyro ...
... geochronologic data, the temporal span of the Rooiberg Group is poorly understood. The Rooiberg Group consists of basaltic to rhyolitic lava erupted from fissural volcanism with estimated eruption temperatures of the rhyolitic lavas exceeding 1000°C. Minor explosive eruptions are represented by pyro ...
Mesa Central of México: Stratigraphy, structure, and Cenozoic
... Mesa Central is located in central-northern México, a semiarid region. Most geological studies in this region have focused on the exploration and exploitation of ore deposits, mainly precious metals. The works published in the nineteenth century, and in the beginnings of the twentieth, describe the ...
... Mesa Central is located in central-northern México, a semiarid region. Most geological studies in this region have focused on the exploration and exploitation of ore deposits, mainly precious metals. The works published in the nineteenth century, and in the beginnings of the twentieth, describe the ...
Correlations between silicic volcanic rocks of the St Mary`s Islands
... therein). Lavas, dykes, other igneous intrusions and deeply altered pyroclastic rocks cover much of the eastern and western coasts and parts of the hinterland (Fig. 1c). In many areas the lavas lie directly on the Precambrian basement. Silicic rocks have been found throughout the province, although ...
... therein). Lavas, dykes, other igneous intrusions and deeply altered pyroclastic rocks cover much of the eastern and western coasts and parts of the hinterland (Fig. 1c). In many areas the lavas lie directly on the Precambrian basement. Silicic rocks have been found throughout the province, although ...
Mineral Deposits in India
... Microthermometric and Raman studies revealed high salinity and minor presence of CH 4. These fluids are inferred to be of oxidized nature that precipitated barite after the gold-forming event at Hutti. SHRIMP U-Pb dating of hydrothermal monazite (+xenotime) from auriferous wall rock alteration zones ...
... Microthermometric and Raman studies revealed high salinity and minor presence of CH 4. These fluids are inferred to be of oxidized nature that precipitated barite after the gold-forming event at Hutti. SHRIMP U-Pb dating of hydrothermal monazite (+xenotime) from auriferous wall rock alteration zones ...
Algoman orogeny
The Algoman orogeny, known as the Kenoran orogeny in Canada, was an episode of mountain-building (orogeny) during the Late Archean Eon that involved repeated episodes of continental collisions, compressions and subductions. The Superior province and the Minnesota River Valley terrane collided about 2,700 to 2,500 million years ago. The collision folded the Earth's crust and produced enough heat and pressure to metamorphose the rock. Blocks were added to the Superior province along a 1,200 km (750 mi) boundary that stretches from present-day eastern South Dakota into the Lake Huron area. The Algoman orogeny brought the Archaen Eon to a close, about 2,500 million years ago; it lasted less than 100 million years and marks a major change in the development of the earth’s crust.The Canadian shield contains belts of metavolcanic and metasedimentary rocks formed by the action of metamorphism on volcanic and sedimentary rock. The areas between individual belts consist of granites or granitic gneisses that form fault zones. These two types of belts can be seen in the Wabigoon, Quetico and Wawa subprovinces; the Wabigoon and Wawa are of volcanic origin and the Quetico is of sedimentary origin. These three subprovinces lie linearly in southwestern- to northeastern-oriented belts about 140 km (90 mi) wide on the southern portion of the Superior Province.The Slave province and portions of the Nain province were also affected. Between about 2,000 and 1,700 million years ago these combined with the Sask and Wyoming cratons to form the first supercontinent, the Kenorland supercontinent.