McLelland, JM, Selleck, BW, and Bickford, ME, 2010
... In recent years, a rapidly expanding database, especially in sensitive high-resolution ion microprobe (SHRIMP) geochronology, has led to significant advances in understanding of the Precambrian tectonic evolution of the Grenville Province, including its Adirondack outlier, and the Mesoproterozoic in ...
... In recent years, a rapidly expanding database, especially in sensitive high-resolution ion microprobe (SHRIMP) geochronology, has led to significant advances in understanding of the Precambrian tectonic evolution of the Grenville Province, including its Adirondack outlier, and the Mesoproterozoic in ...
BELT OROGENESIS ALONG THE NORTHERN MARGIN Charles S
... east of the Canyon ranger station and 15 kilometers north of the Bungalow ranger station in the Clearwater National Forest of northern Idaho, ...
... east of the Canyon ranger station and 15 kilometers north of the Bungalow ranger station in the Clearwater National Forest of northern Idaho, ...
between Earth Expansion and Seafloor Spreading
... In this alternate model based on King, expansion tectonics is divorced from seafloor spreading and wed to oceanization, but only on its own terms and in a much narrower sense. Indeed, this expansion model explains how and why oceanization was triggered in the first place. As the Earth expanded – whi ...
... In this alternate model based on King, expansion tectonics is divorced from seafloor spreading and wed to oceanization, but only on its own terms and in a much narrower sense. Indeed, this expansion model explains how and why oceanization was triggered in the first place. As the Earth expanded – whi ...
38_1993_Houston et al_Geo of NA_Wyoming province
... Wyoming, where the boundary is a major shear m e along which Arehean and Early Proterozoic miogeoclinal rocks on the north are juxtaposed with late Early Proterozoic volcanogenic racks on thg'south. No rocks older than 1,800 Ma have been documented south ofthis shear zone @ePaolo, 1981; Nelson and D ...
... Wyoming, where the boundary is a major shear m e along which Arehean and Early Proterozoic miogeoclinal rocks on the north are juxtaposed with late Early Proterozoic volcanogenic racks on thg'south. No rocks older than 1,800 Ma have been documented south ofthis shear zone @ePaolo, 1981; Nelson and D ...
Seismic structure of the crust and uppermost mantle of the Capricorn
... Following the final suturing of the West Australian Craton during the 2.00–1.95 Ga Glenburgh Orogeny, the province underwent numerous low- to medium-grade tectonothermal intracontinental reworking events, many of which were accompanied by the intrusion of voluminous granitic batholiths (Sheppard et a ...
... Following the final suturing of the West Australian Craton during the 2.00–1.95 Ga Glenburgh Orogeny, the province underwent numerous low- to medium-grade tectonothermal intracontinental reworking events, many of which were accompanied by the intrusion of voluminous granitic batholiths (Sheppard et a ...
Detrital Zircons from Missi Metasedimentary Rocks, Flin Flon Basin
... the Flin Flon Domain (1908 ±3 Ma, Heaman et al., this volume). These or similar rocks are possible sources for zircons in the Missi Group having ages of 1880 to 1950 Ma. The euhedral character of some zircons implies that they may have been derived from a more local source in the western Flin Flon D ...
... the Flin Flon Domain (1908 ±3 Ma, Heaman et al., this volume). These or similar rocks are possible sources for zircons in the Missi Group having ages of 1880 to 1950 Ma. The euhedral character of some zircons implies that they may have been derived from a more local source in the western Flin Flon D ...
Generation of high-silica rhyolite: A Nd, Sr, and O isotopic study of
... thereafter, a lava dome (source of Sample 317 in Tables 1 and 2) erupted in the southcentral part of the lake (Fig. 2) through the area thought to have been the main vent for the Tala Tuff. It was followed by emplacement of a dome (Sample 283) in the northcentral part of the lake. A group of domes ( ...
... thereafter, a lava dome (source of Sample 317 in Tables 1 and 2) erupted in the southcentral part of the lake (Fig. 2) through the area thought to have been the main vent for the Tala Tuff. It was followed by emplacement of a dome (Sample 283) in the northcentral part of the lake. A group of domes ( ...
Amphibious Array Arctic Beaufort Sea RoyOct7
... intervening 400 km wide coastal region extending from the sinistral Canning River Displacement Zone in eastern Alaska to the dextral Richardson-Eskimo (Husky) Lakes Fault zone at the eastern edge of the Mackenzie River Delta in westernmost Northwest Territories, there is a welldeveloped margin fold ...
... intervening 400 km wide coastal region extending from the sinistral Canning River Displacement Zone in eastern Alaska to the dextral Richardson-Eskimo (Husky) Lakes Fault zone at the eastern edge of the Mackenzie River Delta in westernmost Northwest Territories, there is a welldeveloped margin fold ...
Geochronology and thermochronology of Cretaceous
... and associated intrusions from the Bilibino region (Arctic Chukotka, Russia) was carried out using the SHRIMP-RG. The crystallization ages of these granitoids, which range from approximately 116.9±2.5 to 108.5±2.7 Ma, bracket two regionally significant deformational events. The plutons cut folds, st ...
... and associated intrusions from the Bilibino region (Arctic Chukotka, Russia) was carried out using the SHRIMP-RG. The crystallization ages of these granitoids, which range from approximately 116.9±2.5 to 108.5±2.7 Ma, bracket two regionally significant deformational events. The plutons cut folds, st ...
Synthesis of Results From the CD-ROM Experiment
... New Mexico (Plate 1) obliquely crosses numerous Phanerozoic tectonic provinces (Southern Rocky Mountains, Rio Grande rift, Great Plains) and orthogonally crosses northeaststriking structures related to Proterozoic assembly of the crust. The oldest tectonic features, formed during assembly of the con ...
... New Mexico (Plate 1) obliquely crosses numerous Phanerozoic tectonic provinces (Southern Rocky Mountains, Rio Grande rift, Great Plains) and orthogonally crosses northeaststriking structures related to Proterozoic assembly of the crust. The oldest tectonic features, formed during assembly of the con ...
File
... Heat and pressure can cause rocks to go through physical and chemical changes. When this happens we call the rock metamorphic. Metamorphic rocks are rocks that have changed due to heat and or pressure. This pressure can be from the weight of the rocks above or the pressure of the two tectonic plates ...
... Heat and pressure can cause rocks to go through physical and chemical changes. When this happens we call the rock metamorphic. Metamorphic rocks are rocks that have changed due to heat and or pressure. This pressure can be from the weight of the rocks above or the pressure of the two tectonic plates ...
Sinking Slabs and Convection Connections
... • 7c. In general, plates pass over hot spots. There is little, if any, correlation between hot spots and plate direction. For a relatively small number of hot spots on spreading ridges, the plate moves away from the hot spots (e.g., Iceland, Galapagos, or Afar at the base of the Red Sea). Many more ...
... • 7c. In general, plates pass over hot spots. There is little, if any, correlation between hot spots and plate direction. For a relatively small number of hot spots on spreading ridges, the plate moves away from the hot spots (e.g., Iceland, Galapagos, or Afar at the base of the Red Sea). Many more ...
Yilgarn Craton: A case study in regolith formation Major
... The Yilgarn Craton is one of the largest segments of Archaen crust on Earth. It has an area of about 657,000 km2 (26% of WA) and is situated in the Precambrian Western Shield of Australia. Most of the Craton is believed to have been formed between 3,000 and 2500 Ma. The rocks and structures of the C ...
... The Yilgarn Craton is one of the largest segments of Archaen crust on Earth. It has an area of about 657,000 km2 (26% of WA) and is situated in the Precambrian Western Shield of Australia. Most of the Craton is believed to have been formed between 3,000 and 2500 Ma. The rocks and structures of the C ...
full text - NWT Protected Area Strategy
... increases noticeably toward the west. On the western side of the complex, the Archean rocks are predominantly banded gneisses of tonalitic to granitic composition that are intruded by sheets of foliated granite (e.g., Iizuka et al., 2006, 2007). Immediately overlying the AGC to the west and south is ...
... increases noticeably toward the west. On the western side of the complex, the Archean rocks are predominantly banded gneisses of tonalitic to granitic composition that are intruded by sheets of foliated granite (e.g., Iizuka et al., 2006, 2007). Immediately overlying the AGC to the west and south is ...
Tut-4-exam-Q
... Your answer should consist of only 5 letters = A, B, C, F, G. Q2 (a) Discuss the relationship between plate convergence and uplift of narrow mountain belts by considering: (i) how crustal shortening is achieved in the Himalayas. Block 4 sections 7.5 and 7.6. (ii) how this varies along the Himalayan ...
... Your answer should consist of only 5 letters = A, B, C, F, G. Q2 (a) Discuss the relationship between plate convergence and uplift of narrow mountain belts by considering: (i) how crustal shortening is achieved in the Himalayas. Block 4 sections 7.5 and 7.6. (ii) how this varies along the Himalayan ...
GEOL 1010 - Research at UVU
... i) Differentiation occurs when, as the magma first begins to become solid, mafic minerals (rich in Fe (iron), Mg (magnesium) and Ca (calcium)) such as olivine and pyroxene crystallize, sink, and are separated from the magma (recall from Bowen’s Reaction Series that mafic minerals have higher meltin ...
... i) Differentiation occurs when, as the magma first begins to become solid, mafic minerals (rich in Fe (iron), Mg (magnesium) and Ca (calcium)) such as olivine and pyroxene crystallize, sink, and are separated from the magma (recall from Bowen’s Reaction Series that mafic minerals have higher meltin ...
GEOLOGY OF THE KÜTAHYA-BOLKARDAĞ BELT Abstract
... Kütahya-Bolkardağ Belt is one of the subunits of the Tauride-Anatolite Terrane stretching from the Aegean Sea to the Hınzır Mountains. It includes numerous tectonic slices, formed during the closure of the İzmir-Ankara Oceanic branch of the Neotethys. The tectonic slices are mainly derived from thre ...
... Kütahya-Bolkardağ Belt is one of the subunits of the Tauride-Anatolite Terrane stretching from the Aegean Sea to the Hınzır Mountains. It includes numerous tectonic slices, formed during the closure of the İzmir-Ankara Oceanic branch of the Neotethys. The tectonic slices are mainly derived from thre ...
Earth`s Dynamic Syst..
... Continents consist of three major structural components – shields, stable platforms and folded mountain belts. Continental crust is less dense, thicker, older, and more deformed than oceanic crust. The difference in elevation of continents and ocean basins reflects their fundamental difference in co ...
... Continents consist of three major structural components – shields, stable platforms and folded mountain belts. Continental crust is less dense, thicker, older, and more deformed than oceanic crust. The difference in elevation of continents and ocean basins reflects their fundamental difference in co ...
Cr – Chromium
... especially under moderately oxidising and reducing conditions and near-neutral pH values. In soil, Cr behaviour is governed by pH, Eh and organic matter. Its adsorption by clay is also highly dependent on pH; Cr6+ adsorption decreases with increasing pH, and Cr3+ adsorption increases with increasing ...
... especially under moderately oxidising and reducing conditions and near-neutral pH values. In soil, Cr behaviour is governed by pH, Eh and organic matter. Its adsorption by clay is also highly dependent on pH; Cr6+ adsorption decreases with increasing pH, and Cr3+ adsorption increases with increasing ...
Direct geological evidence for oceanic detachment faulting: The Mid
... sedimentary breccias on the surface of the massif. Fault rocks are abundant on the top of the striated surface, or near it along its flanks. They are mylonitic, with strong foliations dipping subparallel to the striated surface in oriented cores (Figs. 3A and 3B). Microstructural observations show t ...
... sedimentary breccias on the surface of the massif. Fault rocks are abundant on the top of the striated surface, or near it along its flanks. They are mylonitic, with strong foliations dipping subparallel to the striated surface in oriented cores (Figs. 3A and 3B). Microstructural observations show t ...
OBJECTIVES: Students will gain an understanding of how
... Scientists refer to the Mid-Atlantic submarine mountainous region as the Mid-Atlantic Ridge. The Theory of Seafloor Spreading states that seafloor spreading is a process that occurs at mid-ocean ridges, where new ocean crust is formed through volcanic activity and then gradually moves away from the ...
... Scientists refer to the Mid-Atlantic submarine mountainous region as the Mid-Atlantic Ridge. The Theory of Seafloor Spreading states that seafloor spreading is a process that occurs at mid-ocean ridges, where new ocean crust is formed through volcanic activity and then gradually moves away from the ...
The Origins of Plate Tectonics Theory
... Before the 1920s, the crust below the seas was thought to be flat and featureless. During World War I, however, ships equipped with sonar began to produce data about the topography of the seafloor. These sonar maps showed the seafloor to be anything but featureless – instead, the ocean floor hosted ...
... Before the 1920s, the crust below the seas was thought to be flat and featureless. During World War I, however, ships equipped with sonar began to produce data about the topography of the seafloor. These sonar maps showed the seafloor to be anything but featureless – instead, the ocean floor hosted ...
Strain localization along the Main Boundary Thrust (MBT) zone in
... (MFT), have emerged from the MHT, striking the entire length of Himalayan mountain belts. These structures accommodated hundreds of kilometers of crustal shortening since India-Asia collision and eventually, juxtaposed different tectono-metamorphic rocks in their hanging wall. Field investigations r ...
... (MFT), have emerged from the MHT, striking the entire length of Himalayan mountain belts. These structures accommodated hundreds of kilometers of crustal shortening since India-Asia collision and eventually, juxtaposed different tectono-metamorphic rocks in their hanging wall. Field investigations r ...
Metamorphic Facies
... A metamorphic petrologist can decipher the times at which a metamorphic rocks of a region were subjected to different P-T conditions. In other words, the evolutionary history of such a region in terms of pressure-temp-time (P-T-t). 1893 George Barrow carried out field-based study in Scotland using m ...
... A metamorphic petrologist can decipher the times at which a metamorphic rocks of a region were subjected to different P-T conditions. In other words, the evolutionary history of such a region in terms of pressure-temp-time (P-T-t). 1893 George Barrow carried out field-based study in Scotland using m ...
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.