Igneous Processes and Landforms
... expansion of gases produces a violent, eruptive blast. Highly viscous, silica-rich magmas and lavas (rhyolitic in composition) have the potential to erupt with violent explosions. Mafic magmas and lavas, such as those with a basaltic composition, are hotter and less viscous (more fluid) and therefor ...
... expansion of gases produces a violent, eruptive blast. Highly viscous, silica-rich magmas and lavas (rhyolitic in composition) have the potential to erupt with violent explosions. Mafic magmas and lavas, such as those with a basaltic composition, are hotter and less viscous (more fluid) and therefor ...
1. Obsidian is a dark, glassy rock that is formed when lava cools
... 1. Obsidian is a dark, glassy rock that is formed when lava cools quickly. It is usually black, but it can also be red, brown, and white specked (snowflake). Obsidian has been used as an arrowhead, a cutting tool, and in jewelry. One of the places where obsidian is found in is the Black Rock Desert ...
... 1. Obsidian is a dark, glassy rock that is formed when lava cools quickly. It is usually black, but it can also be red, brown, and white specked (snowflake). Obsidian has been used as an arrowhead, a cutting tool, and in jewelry. One of the places where obsidian is found in is the Black Rock Desert ...
Forces and Structures ppt
... Fold Mountains (Folded Mountains) • formed when two continental tectonic plates collide and their edges crumble to form mountains • the crust is uplifted forming folds on top of the other ...
... Fold Mountains (Folded Mountains) • formed when two continental tectonic plates collide and their edges crumble to form mountains • the crust is uplifted forming folds on top of the other ...
Earth is made of hard rock
... convection cell that exists in the mantle. Because of this ascending movement, a pressure fall occurs but not a temperature fall (rocks are bad conductors for temperature so they cool very slowly). The pressure fall at a constant temperature drives the peridotite into melting. But this melting is on ...
... convection cell that exists in the mantle. Because of this ascending movement, a pressure fall occurs but not a temperature fall (rocks are bad conductors for temperature so they cool very slowly). The pressure fall at a constant temperature drives the peridotite into melting. But this melting is on ...
3 How does the movement of lithospheric plates cause major events
... 16. Going from the surface to the center of the earth, list the layers in order. Lithosphere (crust), Asthenosphere (mantle), outer core, inner core 17. The earth is layered with a lithosphere that contains the crust and uppermost mantle. 18. The crust is the upper part of the rigid lithosphere and ...
... 16. Going from the surface to the center of the earth, list the layers in order. Lithosphere (crust), Asthenosphere (mantle), outer core, inner core 17. The earth is layered with a lithosphere that contains the crust and uppermost mantle. 18. The crust is the upper part of the rigid lithosphere and ...
Unit 1: Rocks and Minerals
... Earth’s core. The magma that rises then cools and becomes denser as it gets closer to the lithosphere. This cooler, denser magma then sinks as the hotter, less dense magma below it rises. It is this continuous sinking and rising of magma that forms convection currents. (S6E5a) The area where two or ...
... Earth’s core. The magma that rises then cools and becomes denser as it gets closer to the lithosphere. This cooler, denser magma then sinks as the hotter, less dense magma below it rises. It is this continuous sinking and rising of magma that forms convection currents. (S6E5a) The area where two or ...
The REE and rare metal accessory minerals of the A
... minerals in the granite is significant, not only for establishing the magmatic origin of the mineralization, but for revealing several stages of REE and rare metal – mineral formation related to the magmatic evolution of the Wentworth pluton. The early granites contain 200–600 ppm fluorine. The pres ...
... minerals in the granite is significant, not only for establishing the magmatic origin of the mineralization, but for revealing several stages of REE and rare metal – mineral formation related to the magmatic evolution of the Wentworth pluton. The early granites contain 200–600 ppm fluorine. The pres ...
Plate Tectonics PPT
... • The more dense plate slides under the less dense plate creating a subduction zone called a TRENCH ...
... • The more dense plate slides under the less dense plate creating a subduction zone called a TRENCH ...
The Geologic Time Scale
... the forces that continually change the surface features of Earth today have been occurring since Earth formed. • Only the rate, intensity, and scale with which the forces occur have changed. • The resulting sediments and rocks all record an environment and fossils within the rocks preserve evidence ...
... the forces that continually change the surface features of Earth today have been occurring since Earth formed. • Only the rate, intensity, and scale with which the forces occur have changed. • The resulting sediments and rocks all record an environment and fossils within the rocks preserve evidence ...
The Geologic Time Scale
... the forces that continually change the surface features of Earth today have been occurring since Earth formed. • Only the rate, intensity, and scale with which the forces occur have changed. • The resulting sediments and rocks all record an environment and fossils within the rocks preserve evidence ...
... the forces that continually change the surface features of Earth today have been occurring since Earth formed. • Only the rate, intensity, and scale with which the forces occur have changed. • The resulting sediments and rocks all record an environment and fossils within the rocks preserve evidence ...
46_1996_Ilg et al_GSABull_Tectonic evolution in GC
... Schists, here collectively named the “Granite Gorge Metamorphic Suite.” The Brahma Schist consists of mafic to intermediate-composition metavolcanic rocks that have yielded an age of 1750 Ma. The Rama Schist consists of felsic metavolcanic rocks that have yielded an age of 1742 Ma. On the basis of t ...
... Schists, here collectively named the “Granite Gorge Metamorphic Suite.” The Brahma Schist consists of mafic to intermediate-composition metavolcanic rocks that have yielded an age of 1750 Ma. The Rama Schist consists of felsic metavolcanic rocks that have yielded an age of 1742 Ma. On the basis of t ...
The Virgin River Shear Zone in the Careen Lake Area: Field
... due largely to the effect of ductile deformation. Later brittle faulting is both oblique and parallel to the main mylonitic fabric. Along the mylonitic fabric plane, pegmatite and granitic dykes show dextral offset. Two conjugate brittle fault sets are also present. One set, oriented at approximatel ...
... due largely to the effect of ductile deformation. Later brittle faulting is both oblique and parallel to the main mylonitic fabric. Along the mylonitic fabric plane, pegmatite and granitic dykes show dextral offset. Two conjugate brittle fault sets are also present. One set, oriented at approximatel ...
Proterozoic Tectonics: An Indian Perspective
... emplacement of reported ophiolites around 1.85 Ga. Another phase of rifting followed, that is correlated with the break-up of Columbia. This evolved once again into an arc-type environment with addition of new continental crust in the Mesoproterozoic and renewed emplacement of ophiolites. The proces ...
... emplacement of reported ophiolites around 1.85 Ga. Another phase of rifting followed, that is correlated with the break-up of Columbia. This evolved once again into an arc-type environment with addition of new continental crust in the Mesoproterozoic and renewed emplacement of ophiolites. The proces ...
Preliminary geochemical data for dolerite dykes and sills of the
... basic nature of the dolerites compared to the basalts. However, thin flows of olivine-phyric basalt have been found recently near the base of the volcanic succession in the volcanic remnants south of the Huab River (Milner & Ewart, 1989). These lavas would clearly extend the known compositional rang ...
... basic nature of the dolerites compared to the basalts. However, thin flows of olivine-phyric basalt have been found recently near the base of the volcanic succession in the volcanic remnants south of the Huab River (Milner & Ewart, 1989). These lavas would clearly extend the known compositional rang ...
Physical Processes Along Internal Boundaries In An Con
... juxtaposed magma batches, complex flow along these boundaries, and late fabric formation during emplacement of progressively younger magma pulses and regional tectonic strain. The Tuolumne Batholith is a large composite batholith exposed in the central Sierra Nevada (California, USA), emplaced as a ...
... juxtaposed magma batches, complex flow along these boundaries, and late fabric formation during emplacement of progressively younger magma pulses and regional tectonic strain. The Tuolumne Batholith is a large composite batholith exposed in the central Sierra Nevada (California, USA), emplaced as a ...
Sea Floor Spreading – 1956-1963
... - inclined zones of earthquakes down to 700 km - linked to oceanic trenches and volcanos? 4) What is the mechanism of heat loss of the earth? Conduction or convection? If convection how is it related to geology? ...
... - inclined zones of earthquakes down to 700 km - linked to oceanic trenches and volcanos? 4) What is the mechanism of heat loss of the earth? Conduction or convection? If convection how is it related to geology? ...
Ashley Project Targeting
... northeast, between the Argyle, McGill and Sunisloe gold occurrences. The arcuate feature, roughly orthogonal to the volcanic sequence, terminates at its north in a circular multielement soil anomaly over the west margin of a syenite stock. The geochemistry and geophysics together are interpreted as ...
... northeast, between the Argyle, McGill and Sunisloe gold occurrences. The arcuate feature, roughly orthogonal to the volcanic sequence, terminates at its north in a circular multielement soil anomaly over the west margin of a syenite stock. The geochemistry and geophysics together are interpreted as ...
APS Continental Crust RLR.pptx
... Felsic crustal material removed from upper plate by subduction erosion is relaminated to the ...
... Felsic crustal material removed from upper plate by subduction erosion is relaminated to the ...
Geological Society of Malaysia Bulletin 49
... indicate a Late Permian age. The area was intruded by the Permo-Carboniferous mafic to intermediate igneous rocks, followed by the Late Permian-Early Triassic biotite granite and the Late Triassic granite and finally by the Jurassic-Cretaceous dolerite dykes. Most of the interpreted Carboniferous me ...
... indicate a Late Permian age. The area was intruded by the Permo-Carboniferous mafic to intermediate igneous rocks, followed by the Late Permian-Early Triassic biotite granite and the Late Triassic granite and finally by the Jurassic-Cretaceous dolerite dykes. Most of the interpreted Carboniferous me ...
LATE CENOZOIC OROGENY IN JAPAN Late Cenozoic tectonic
... young sediments and young faulting (Ludwig et al., 1966). The outer belt corresponds to the non-volcanic outer arc of the double arc (Umbgrove, 1947). The outer belt of northeast Honshu Arc consists mostly of metamorphosed Paleozoic rocks and Mesozoic granite and sedimentaries. This belt has been ra ...
... young sediments and young faulting (Ludwig et al., 1966). The outer belt corresponds to the non-volcanic outer arc of the double arc (Umbgrove, 1947). The outer belt of northeast Honshu Arc consists mostly of metamorphosed Paleozoic rocks and Mesozoic granite and sedimentaries. This belt has been ra ...
Gey205_1
... fossils are marine organisms, but certain land organisms are useful in young rocks and in specific regions.The best index fossils have four characteristics: They are unique, prevalent, plentiful and restricted in geologic time. Most fossils are from ocean rocks, so most major index fossils are from ...
... fossils are marine organisms, but certain land organisms are useful in young rocks and in specific regions.The best index fossils have four characteristics: They are unique, prevalent, plentiful and restricted in geologic time. Most fossils are from ocean rocks, so most major index fossils are from ...
Stratigraphic Principles
... rock layers. Major focuses include geochronology, comparative geology, and petrology. In general a stratum will be primarily igneous or sedimentary relating to how the rock was formed. ...
... rock layers. Major focuses include geochronology, comparative geology, and petrology. In general a stratum will be primarily igneous or sedimentary relating to how the rock was formed. ...
tectonics2a
... There are several large tectonic plates and a number of much smaller plates. The Earth’s continents sit on plates composed of both oceanic and continental crust. The huge Pacific plate is composed almost entirely of oceanic crust, and is being subducted around almost its entire western ...
... There are several large tectonic plates and a number of much smaller plates. The Earth’s continents sit on plates composed of both oceanic and continental crust. The huge Pacific plate is composed almost entirely of oceanic crust, and is being subducted around almost its entire western ...
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.