Magma Emplacement Room Problem How to Accommodate Plutons
... • An example: the Sierra Nevada Batholith, CA • A group or groups of separately intruded plutons with a composite volume of 106 km3 • Age extends through the Mesozoic (>130 my) • Average pluton volume is ~ 30 km3 ...
... • An example: the Sierra Nevada Batholith, CA • A group or groups of separately intruded plutons with a composite volume of 106 km3 • Age extends through the Mesozoic (>130 my) • Average pluton volume is ~ 30 km3 ...
12.710, Spring 2014, Problem Set 5, Isostacy Isostacy is the concept
... Surprisingly, the simple relationship between extension, isostacy, and basin formation was only appreciated in the 1970's, after plate tectonics began to be accepted; this despite the fact the all of the world's petroleum resources are derived from sedimentary rocks deposited in basins formed throug ...
... Surprisingly, the simple relationship between extension, isostacy, and basin formation was only appreciated in the 1970's, after plate tectonics began to be accepted; this despite the fact the all of the world's petroleum resources are derived from sedimentary rocks deposited in basins formed throug ...
Research Note How Genuine is the Circum
... surrounded by an almost continuous belt of seismicity and volcanism--“the fiery ring of the Pacific”. This has led to an impression of uniformity in the structure and tectonics of the lands surrounding and immediately bordering the Pacific Ocean. For example, Benioff (1958, 1962), Aki (1960) and oth ...
... surrounded by an almost continuous belt of seismicity and volcanism--“the fiery ring of the Pacific”. This has led to an impression of uniformity in the structure and tectonics of the lands surrounding and immediately bordering the Pacific Ocean. For example, Benioff (1958, 1962), Aki (1960) and oth ...
earth sciences 3313a igneous petrology
... mechanisms and processes controlling volcanic eruptions. It is also clear that the materials which constitute the Earth’s atmosphere, oceans, and crust ultimately originated from the Earth’s interior and were brought to the Earth’s surface via igneous processes. Consequently igneous petrology is a k ...
... mechanisms and processes controlling volcanic eruptions. It is also clear that the materials which constitute the Earth’s atmosphere, oceans, and crust ultimately originated from the Earth’s interior and were brought to the Earth’s surface via igneous processes. Consequently igneous petrology is a k ...
Laxmi Ridge - Northern Seychelles Bank, Western Indian
... 13 (Fig. 4), were also collected in the area. 32 OBS were deployed along the main line and 21 land seismometers were installed on the islands for the wide-angle work (Fig. 3). On MCS profiles, top oceanic basement and Moho are imaged at 6.5 s and 8 s twt, respectively, indicating that the early ocea ...
... 13 (Fig. 4), were also collected in the area. 32 OBS were deployed along the main line and 21 land seismometers were installed on the islands for the wide-angle work (Fig. 3). On MCS profiles, top oceanic basement and Moho are imaged at 6.5 s and 8 s twt, respectively, indicating that the early ocea ...
SCIENCE CHINA Magmatism during continental collision
... 2010), with a 12–15 Myr gap from the initial collision. Some researchers suggested that the uplift of the Himalaya Orogen began at 50 Ma (An et al., 2001), which is contemporaneous with the UHP metamorphism. Up to now, the India plate is still moving northward at a speed of 3–4 cm yr−1. Therefore, f ...
... 2010), with a 12–15 Myr gap from the initial collision. Some researchers suggested that the uplift of the Himalaya Orogen began at 50 Ma (An et al., 2001), which is contemporaneous with the UHP metamorphism. Up to now, the India plate is still moving northward at a speed of 3–4 cm yr−1. Therefore, f ...
L01 - D4 - Teacher - Inside the Earth
... igneous (once molten) and sedimentary rocks (made by weathering / erosion and compression). The temperature can be as hot as 6000C. The crust itself is a relatively thin solid layer and is in two categories: continental and oceanic. Continental Crust (mainly Granite – density ~ 2.7 g/cm3) The cont ...
... igneous (once molten) and sedimentary rocks (made by weathering / erosion and compression). The temperature can be as hot as 6000C. The crust itself is a relatively thin solid layer and is in two categories: continental and oceanic. Continental Crust (mainly Granite – density ~ 2.7 g/cm3) The cont ...
Pseudotachylytes, related fault rocks, asperities, and crustal structures in the
... (Table 1). They are inconsistent with and post-date the D3 -mylonite-generating tectonics. Furthermore, their formation may have post-dated or followed the Ds-mylonitegenerating tectonics, because they are not mylonitized but related to cataclastic deformation (Table 1). The layer-parallel pseudotac ...
... (Table 1). They are inconsistent with and post-date the D3 -mylonite-generating tectonics. Furthermore, their formation may have post-dated or followed the Ds-mylonitegenerating tectonics, because they are not mylonitized but related to cataclastic deformation (Table 1). The layer-parallel pseudotac ...
Geochemistry of an island-arc plutonic suite
... Abstract--The Wadi Dabr intrusive complex, west of Mersa-Alam, Eastern Desert, Egypt ranges in composition from gabbro to diorite, quartz diorite and tonalite. The gabbroic rocks include pyroxene-hornblende gabbro, hornblende gabbro, quartz-hornblende gabbro, metagabbro and amphibolite. Mineral chem ...
... Abstract--The Wadi Dabr intrusive complex, west of Mersa-Alam, Eastern Desert, Egypt ranges in composition from gabbro to diorite, quartz diorite and tonalite. The gabbroic rocks include pyroxene-hornblende gabbro, hornblende gabbro, quartz-hornblende gabbro, metagabbro and amphibolite. Mineral chem ...
Kinematic evolution of the Greater Himalayan Sequence
... samples collected along a N-S transect through the Kali Gandaki Valley, in the Annapurna-Dhaulagiri Himalaya of central Nepal. Intensity, I (Lisle, 1985) which is used to describe the strength of each CPO fabric is calculated for each sample and stratigraphically arranged into a single plot to produ ...
... samples collected along a N-S transect through the Kali Gandaki Valley, in the Annapurna-Dhaulagiri Himalaya of central Nepal. Intensity, I (Lisle, 1985) which is used to describe the strength of each CPO fabric is calculated for each sample and stratigraphically arranged into a single plot to produ ...
Processes of Magma Evolution and Magmatic Suites
... magmas, which are very small in volume but have a paramount petrological and geodynamic importance. These encompass lamproites and kimberlites, which almost exclusively are erupted in continental settings. These magmas are characterized by a variable degree of silica undersaturation and a high potas ...
... magmas, which are very small in volume but have a paramount petrological and geodynamic importance. These encompass lamproites and kimberlites, which almost exclusively are erupted in continental settings. These magmas are characterized by a variable degree of silica undersaturation and a high potas ...
PLATE TECTONICS - New Jersey City University
... split up 200 m.y. Continents in motion for at least 2 billion ...
... split up 200 m.y. Continents in motion for at least 2 billion ...
Unraveling the Tapestry of Ocean Crust
... cools, it becomes denser and ultimately sinks back into the mantle under its own weight after about 200 million years. Earth’s continental crust, on the other hand, is up to 4 billion years old, and it is thought to be the product of geologic recycling processes far more complicated than those that ...
... cools, it becomes denser and ultimately sinks back into the mantle under its own weight after about 200 million years. Earth’s continental crust, on the other hand, is up to 4 billion years old, and it is thought to be the product of geologic recycling processes far more complicated than those that ...
Geology and Geotectonic Setting of the Basement Complex
... on the outcrops. This amphibolite variety is composed of hornblende, actinolite and tremolite. In thin section the mineral composition includes (apart from the above) magnetite, sphene calcite and minor monazite and zircon. The skeletal olivine contains small, opaque inclusions which are probably ma ...
... on the outcrops. This amphibolite variety is composed of hornblende, actinolite and tremolite. In thin section the mineral composition includes (apart from the above) magnetite, sphene calcite and minor monazite and zircon. The skeletal olivine contains small, opaque inclusions which are probably ma ...
church_hall
... crustformation. Allerton and Vin furthered argued that the Solea Graben was formed by off-axis extension during lulls in the supply of magma to an intermediate to fast-spreading axis, in which case the relationship between ores and magma supply becomes debatable. Furthermore, Varga and Moores (1985, ...
... crustformation. Allerton and Vin furthered argued that the Solea Graben was formed by off-axis extension during lulls in the supply of magma to an intermediate to fast-spreading axis, in which case the relationship between ores and magma supply becomes debatable. Furthermore, Varga and Moores (1985, ...
Advances in the geology of the Tobacco Root Mountains, Montana
... shear and transposition of compositional layering, and the degree to which isotopic geochronometers were reset demonstrate an event that was orogenic in character and scope. Because the evidence for this orogeny and most of its known effects are found in Montana, we designate this the Big Sky orogen ...
... shear and transposition of compositional layering, and the degree to which isotopic geochronometers were reset demonstrate an event that was orogenic in character and scope. Because the evidence for this orogeny and most of its known effects are found in Montana, we designate this the Big Sky orogen ...
Evidence for melting of garnet pyroxenite in the generation of
... signatures. These include: (1) melt generation through very small degree melting of a depleted mantle source (e.g. Frey and Roden, 1987); (2) melt generation from a recently metasomatized mantle source (e.g. Clague and Frey, 1982); and (3) incompatible-element enrichment via melt/mantle interaction ...
... signatures. These include: (1) melt generation through very small degree melting of a depleted mantle source (e.g. Frey and Roden, 1987); (2) melt generation from a recently metasomatized mantle source (e.g. Clague and Frey, 1982); and (3) incompatible-element enrichment via melt/mantle interaction ...
Plate Tectonics 2 ppt
... Compare this cross section with the one you envisioned Andes (mountains and volcanoes) over subduction zone, with trench offshore ...
... Compare this cross section with the one you envisioned Andes (mountains and volcanoes) over subduction zone, with trench offshore ...
LITHOGEOCHEMISTRY OF ULTRAMAFIC, GABBROIC AND
... classifies the ultramafic and mafic rocks and evaluates a possible petrogenetic relationship with the calc-alkaline, tonalitic granitoid rocks in the complex. The potential of these rocks to host Ni, Cu, Co, Au and platinum-group element (PGE) mineralization is also examined. ...
... classifies the ultramafic and mafic rocks and evaluates a possible petrogenetic relationship with the calc-alkaline, tonalitic granitoid rocks in the complex. The potential of these rocks to host Ni, Cu, Co, Au and platinum-group element (PGE) mineralization is also examined. ...
New Investigations of Basement to the Western Athabasca Basin
... psammopelitic rocks and garnet diatexite, but also contains psammite, garnet-orthopyroxene diatexite, and rare boudins or blocks of quartzite, pelitic restite, amphibolite, and ultramafic rock. Psammopelites are grey and medium grained (Figure 3) with fresh examples containing 5 to 10% biotite and 1 ...
... psammopelitic rocks and garnet diatexite, but also contains psammite, garnet-orthopyroxene diatexite, and rare boudins or blocks of quartzite, pelitic restite, amphibolite, and ultramafic rock. Psammopelites are grey and medium grained (Figure 3) with fresh examples containing 5 to 10% biotite and 1 ...
Geochemical cycle of volatiles during plate
... high solubility of H2O in wadsleyite (Mg2SiO4), ~3.3 wt.%, influences the pressure and pressure interval of the olivine to wadsleyite phase transformation that is the cause of the 410-km seismic discontinuity. Using multianvil apparatus experiments in the Mg2SiO4–H2O system we demonstrate that the w ...
... high solubility of H2O in wadsleyite (Mg2SiO4), ~3.3 wt.%, influences the pressure and pressure interval of the olivine to wadsleyite phase transformation that is the cause of the 410-km seismic discontinuity. Using multianvil apparatus experiments in the Mg2SiO4–H2O system we demonstrate that the w ...
Structural Geology
... • Folds in rocks range from microscopic to hundreds of kilometers across. • Faults are fractures along which displacement has occurred. • Joints are fractures where there has been no displacement. • Rocks deform when applied stress exceeds rock strength. Deformation may be ductile flow or brittle fr ...
... • Folds in rocks range from microscopic to hundreds of kilometers across. • Faults are fractures along which displacement has occurred. • Joints are fractures where there has been no displacement. • Rocks deform when applied stress exceeds rock strength. Deformation may be ductile flow or brittle fr ...
Northern Flin Flon Belt compilation, Manitoba (parts of NTS 63K12, 13)
... sinistral displacement in the NFFB, inferred as a result of oblique-slip movement along the fault (Figures GS-7-2 and -3). The Northeast Arm shear zone is a crustal-scale feature (David and Syme, 1994; Lucas et al., 1996) that divides the NFFB into two structurally distinct subareas: west of the she ...
... sinistral displacement in the NFFB, inferred as a result of oblique-slip movement along the fault (Figures GS-7-2 and -3). The Northeast Arm shear zone is a crustal-scale feature (David and Syme, 1994; Lucas et al., 1996) that divides the NFFB into two structurally distinct subareas: west of the she ...
Hudson Bay Lithospheric Experiment (HUBLE)
... several reasons. Firstly, the ability to monitor station state-of health from the UK has had important implications for the targeting of efforts during expensive annual service runs. In 2009, for example, poor weather meant that our Twin Otter air time was reduced, so we focused solely on stations th ...
... several reasons. Firstly, the ability to monitor station state-of health from the UK has had important implications for the targeting of efforts during expensive annual service runs. In 2009, for example, poor weather meant that our Twin Otter air time was reduced, so we focused solely on stations th ...
BANDED GNEISSES OF EIGHT LOCALITIES G eneral S tatemen t.
... Locally, each of these gneiss units appears to have been metaso matized and migmatized. The origin suggested for the Randesund area gneisses of Norway ( DIETRICH, 1960a), i. e. chiefly essentially isochemi caP metamorphism of supracrustal rocks, would appear to be appli cable, with slight modific ...
... Locally, each of these gneiss units appears to have been metaso matized and migmatized. The origin suggested for the Randesund area gneisses of Norway ( DIETRICH, 1960a), i. e. chiefly essentially isochemi caP metamorphism of supracrustal rocks, would appear to be appli cable, with slight modific ...
Baltic Shield
The Baltic Shield (sometimes referred to as the Fennoscandian Shield) is located in Fennoscandia (Norway, Sweden and Finland), northwest Russia and under the Baltic Sea. The Baltic Shield is defined as the exposed Precambrian northwest segment of the East European Craton. It is composed mostly of Archean and Proterozoic gneisses and greenstones which have undergone numerous deformations through tectonic activity (see Geology of Fennoscandia map [1]). The Baltic Shield contains the oldest rocks of the European continent. The lithospheric thickness is about 200-300 km. During the Pleistocene epoch, great continental ice sheets scoured and depressed the shield's surface, leaving a thin covering of glacial material and innumerable lakes and streams. The Baltic Shield is still rebounding today following the melting of the thick glaciers during the Quaternary Period.