Post-collision, Shoshonitic Volcanism on the Tibetan Plateau
... provides the best modern example of continental greater than 10 km . The plateau is bounded to the collision plate tectonics. Associated with the north by the Tarim basin, and to the south by the development of this orogen, and formed as a con- Himalaya (extending to the west in Pakistan as the sequ ...
... provides the best modern example of continental greater than 10 km . The plateau is bounded to the collision plate tectonics. Associated with the north by the Tarim basin, and to the south by the development of this orogen, and formed as a con- Himalaya (extending to the west in Pakistan as the sequ ...
Guidebook
... have isotopic signatures characteristic of a mantle derivation. The isotopic signatures of younger plutons show evidence of an increasing crust to mantle ratio, with the latest magmas being entirely crustally derived. This evolution is interpreted as the result of arc thickening and lower arc meltin ...
... have isotopic signatures characteristic of a mantle derivation. The isotopic signatures of younger plutons show evidence of an increasing crust to mantle ratio, with the latest magmas being entirely crustally derived. This evolution is interpreted as the result of arc thickening and lower arc meltin ...
2. - Teacher Friendly Guides
... science is a subject to be explored in one’s own neighborhood, examining the detailed sequence of rocks for the history that has gone on under our feet. What is not possible from only one location is making sense of why this particular sequence of events took place when and where it did, particularl ...
... science is a subject to be explored in one’s own neighborhood, examining the detailed sequence of rocks for the history that has gone on under our feet. What is not possible from only one location is making sense of why this particular sequence of events took place when and where it did, particularl ...
The Cretaceous and Cenozoic tectonic evolution of
... zones give a glimpse of the older Meso- and Paleo-Tethyan oceanic domains (Seton et al., 2012). For example, the only preserved oceanic crust of the latest Jurassic seafloor spreading episode is contained in the obducted basement of the central ophiolite belt on New Guinea (Fig. 1b), likely preserve ...
... zones give a glimpse of the older Meso- and Paleo-Tethyan oceanic domains (Seton et al., 2012). For example, the only preserved oceanic crust of the latest Jurassic seafloor spreading episode is contained in the obducted basement of the central ophiolite belt on New Guinea (Fig. 1b), likely preserve ...
Wadhwan Formation of Western India
... single factor but a group of factors are responsible for detrital composition of a sandstone which include the types of source rocks, distance of transport, tectonism, palaeoclimate, paleogeography and depositional environments and diagenetic modifications of the original detrital constituents. Iden ...
... single factor but a group of factors are responsible for detrital composition of a sandstone which include the types of source rocks, distance of transport, tectonism, palaeoclimate, paleogeography and depositional environments and diagenetic modifications of the original detrital constituents. Iden ...
M116 Tuscarora text - University of Nevada, Reno
... The Tuscarora Quadrangle lies in the northern Tuscarora Mountains in western Elko County in northeastern Nevada (figs. 1, 2). The quadrangle covers the southeastern part of the Tuscarora volcanic field, which is the largest Eocene volcanic field in Nevada, and the southern part of Independence Valle ...
... The Tuscarora Quadrangle lies in the northern Tuscarora Mountains in western Elko County in northeastern Nevada (figs. 1, 2). The quadrangle covers the southeastern part of the Tuscarora volcanic field, which is the largest Eocene volcanic field in Nevada, and the southern part of Independence Valle ...
Multi-Stage Origin of the Coast Range Ophiolite, Supra-Subduction Zone Ophiolites
... interpretation that the Coast Range ophiolite formed to a large extent by rapid extension in the forearc region of a nascent subduction zone. Closer inspection of these data, however, along with detailed studies of field relationships at several locales, show that formation of the ophiolite was more ...
... interpretation that the Coast Range ophiolite formed to a large extent by rapid extension in the forearc region of a nascent subduction zone. Closer inspection of these data, however, along with detailed studies of field relationships at several locales, show that formation of the ophiolite was more ...
Thermal modelling of the Laramide orogeny: testing the £at
... uncertainties in the modelling of mantle wedge dynamics that this point is inconclusive. If frictional heating along the subduction interface, and/or a non-linear mantle wedge rheology are used in these models (e.g. [24]), the mantle wedge and subducting slab will be hotter, such that slab dehydrati ...
... uncertainties in the modelling of mantle wedge dynamics that this point is inconclusive. If frictional heating along the subduction interface, and/or a non-linear mantle wedge rheology are used in these models (e.g. [24]), the mantle wedge and subducting slab will be hotter, such that slab dehydrati ...
GSA Bulletin: Late Cenozoic tectonics of the central and southern
... Cruz Mountains, flowing out onto a coastal alluvial plain near Watsonville, and Alameda Creek crosses the East Bay Hills in a steep-sided canyon, debouching onto an alluvial fan that descends to San Francisco Bay. Because these streams flow upon aggraded surfaces before and after crossing the mounta ...
... Cruz Mountains, flowing out onto a coastal alluvial plain near Watsonville, and Alameda Creek crosses the East Bay Hills in a steep-sided canyon, debouching onto an alluvial fan that descends to San Francisco Bay. Because these streams flow upon aggraded surfaces before and after crossing the mounta ...
The Architecture, Chemistry, and Evolution of - Cin
... subduction magmatism where the upper plate is continental and/or accreted transitional lithosphere. The active-type example is the Andean arc of South America. Well-studied deeply exhumed analogs to the Andean volcanic arc occur as composite batholiths along western North America. The South and Nort ...
... subduction magmatism where the upper plate is continental and/or accreted transitional lithosphere. The active-type example is the Andean arc of South America. Well-studied deeply exhumed analogs to the Andean volcanic arc occur as composite batholiths along western North America. The South and Nort ...
Petrology and Geochemistry of the Nipissing Gabbro
... included in the report and users may wish to verify critical information. If you wish to reproduce any of the text, tables or illustrations in this report, please write for permission to the Manager, Publication Services Section, Ministry of Northern Development and Mines, 933 Ramsey Lake Road, Leve ...
... included in the report and users may wish to verify critical information. If you wish to reproduce any of the text, tables or illustrations in this report, please write for permission to the Manager, Publication Services Section, Ministry of Northern Development and Mines, 933 Ramsey Lake Road, Leve ...
Late Cretaceous and Paleogene tectonic evolution of
... complexities of the Chinook-Emperor trough region. Farrar and Dixon [25] suggested that the Emperor trough is part of a long northwest-southeast wrench fault system extending south through the Line Islands. The proposed fault was considered to be active during early Tertiary time and its presumed 17 ...
... complexities of the Chinook-Emperor trough region. Farrar and Dixon [25] suggested that the Emperor trough is part of a long northwest-southeast wrench fault system extending south through the Line Islands. The proposed fault was considered to be active during early Tertiary time and its presumed 17 ...
Structural control on present-day topography of a basement massif
... The Anti-Atlas basement massif extends South of the High Atlas, and, despite a very mild Cenozoic deformation, its altitude exceeds 1500m in large areas, reaching 3305m in Jbel Sirwa. Structural contours of the present elevation of a polygenic planation surface (the High Erosional surface) and of th ...
... The Anti-Atlas basement massif extends South of the High Atlas, and, despite a very mild Cenozoic deformation, its altitude exceeds 1500m in large areas, reaching 3305m in Jbel Sirwa. Structural contours of the present elevation of a polygenic planation surface (the High Erosional surface) and of th ...
A crustal transect across the Oman Mountains
... order to rectify this omission, we made a 255-km-long, southwesterly oriented crustal transect of the Oman Mountains from the Coastal Zone to the interior Foreland via the 3,000-m-high Jebel Akhdar. The model for the upper 8 km of the crust was constrained using 152 km of 2-D seismic reflection prof ...
... order to rectify this omission, we made a 255-km-long, southwesterly oriented crustal transect of the Oman Mountains from the Coastal Zone to the interior Foreland via the 3,000-m-high Jebel Akhdar. The model for the upper 8 km of the crust was constrained using 152 km of 2-D seismic reflection prof ...
loch loyal syenite complex
... Loyal mass and forms an imposing conical hill rising above the Moine rocks. On the early maps of the Geological Survey it is shown connected to the Ben Loyal intrusion in the poorly exposed ground at the head of Allt Torr an Tairbh, but mapping and geophysical work reported by Robertson and Parsons ...
... Loyal mass and forms an imposing conical hill rising above the Moine rocks. On the early maps of the Geological Survey it is shown connected to the Ben Loyal intrusion in the poorly exposed ground at the head of Allt Torr an Tairbh, but mapping and geophysical work reported by Robertson and Parsons ...
Yin and yang of continental crust creation and destruction by plate
... Figure 2. Estimated continental growth rates on a cumulative basis. Dashed lines show that either continuous production of 1.75 km3/y (lower line) attended by no recycling losses could produce all continental crust that presently exists (7.2 × 109 km3) or that continuous destruction at a rate of 2.6 ...
... Figure 2. Estimated continental growth rates on a cumulative basis. Dashed lines show that either continuous production of 1.75 km3/y (lower line) attended by no recycling losses could produce all continental crust that presently exists (7.2 × 109 km3) or that continuous destruction at a rate of 2.6 ...
Introduction to Metamorphism
... Deviatoric stresses come in three principal types: • Tension: σ3 is negative, and resulting strain is extension, or pulling apart • Compression: σ1 is dominant, results in folding or more homogenous flattening • Shear motion occurs along planes at an angle to σ1 ...
... Deviatoric stresses come in three principal types: • Tension: σ3 is negative, and resulting strain is extension, or pulling apart • Compression: σ1 is dominant, results in folding or more homogenous flattening • Shear motion occurs along planes at an angle to σ1 ...
Kinematic model for the Main Central thrust in Nepal
... detailed studies, the kinematic history of the fault and its relationship to the other structures in the Himalaya remain poorly understood. Particularly intriguing are geochronologic and thermochronologic data from central and eastern Nepal that suggest major reactivation of the Main Central thrust, ...
... detailed studies, the kinematic history of the fault and its relationship to the other structures in the Himalaya remain poorly understood. Particularly intriguing are geochronologic and thermochronologic data from central and eastern Nepal that suggest major reactivation of the Main Central thrust, ...
Crustal contributions to arc magmatism in the Andes of Central Chile
... in Table 1, which gives some essential compositional and morphological data for each. All are andesite-dacite stratovolcanoes, simple or compound, except that Tupungato is dominated by a dacite dome cluster having an apron of derivative block-and-ash flows, and the Planehon and Antuco cones are basa ...
... in Table 1, which gives some essential compositional and morphological data for each. All are andesite-dacite stratovolcanoes, simple or compound, except that Tupungato is dominated by a dacite dome cluster having an apron of derivative block-and-ash flows, and the Planehon and Antuco cones are basa ...
Relations between sedimentary basins and petroleum
... geodesy, earthquakes and magnetic anomalies for past movements. The flow of the plates, its westward polarization and the greater velocity of plates at low latitudes suggest that plate tectonics is influenced by the Earth’s rotation. The concentration of the mantle also seems to support this hypothe ...
... geodesy, earthquakes and magnetic anomalies for past movements. The flow of the plates, its westward polarization and the greater velocity of plates at low latitudes suggest that plate tectonics is influenced by the Earth’s rotation. The concentration of the mantle also seems to support this hypothe ...
9. Metasomatism and metasomatic rocks
... feldspar, sodic amphibole and sodic pyroxene; nepheline, calcite and biotite/phlogopite may also be present and typical accessories are titanite and apatite. Fenites occur as zoned aureoles around alkaline igneous complexes, forming in a wide range of host lithologies. They occur on the metre- to ki ...
... feldspar, sodic amphibole and sodic pyroxene; nepheline, calcite and biotite/phlogopite may also be present and typical accessories are titanite and apatite. Fenites occur as zoned aureoles around alkaline igneous complexes, forming in a wide range of host lithologies. They occur on the metre- to ki ...
Provenance of zircon of the lowermost sedimentary cover, Estonia
... KONSA, MARE and PUURA, VÄINÖ 1999. Provenance of zircon of the lowermost sedimentary cover, Estonia, East-European Craton. Bulletin of the Geological Society of Finland, Number 71, Part 2, 253-273. Bulk and accessory mineral composition of fresh and weathered crystalline rocks, and sedimentary depos ...
... KONSA, MARE and PUURA, VÄINÖ 1999. Provenance of zircon of the lowermost sedimentary cover, Estonia, East-European Craton. Bulletin of the Geological Society of Finland, Number 71, Part 2, 253-273. Bulk and accessory mineral composition of fresh and weathered crystalline rocks, and sedimentary depos ...
Leseane_okstate_0664M_13248
... Elevation Data (GTOPO30, 1 km spatial resolution) showing the different parts of the Southwestern Branch of the East African Rift System. A=Afar. MER=Main Ethiopian Rift. R. Rhino graben. AL=Albertine graben. TA=Tarkana rift. TD=Tanzania divergence. K. Kivu rift. T=Tanganyika rift. RU=Rukwa rift. M= ...
... Elevation Data (GTOPO30, 1 km spatial resolution) showing the different parts of the Southwestern Branch of the East African Rift System. A=Afar. MER=Main Ethiopian Rift. R. Rhino graben. AL=Albertine graben. TA=Tarkana rift. TD=Tanzania divergence. K. Kivu rift. T=Tanganyika rift. RU=Rukwa rift. M= ...
Mechanical (de-)coupling of the lithosphere in the Valencia Trough
... The rift basin started to open during Late Oligocene over an inverted Mesozoic basin that was subjected to non-deposition and erosion during most of the Paleogene [33]. It appears that the opening was not synchronous all over the basin [34], but that rifting commenced earlier in the northeast (Late ...
... The rift basin started to open during Late Oligocene over an inverted Mesozoic basin that was subjected to non-deposition and erosion during most of the Paleogene [33]. It appears that the opening was not synchronous all over the basin [34], but that rifting commenced earlier in the northeast (Late ...
Great Lakes tectonic zone
The Great Lakes tectonic zone is bounded by South Dakota at its tip and heads northeast to south of Duluth, Minnesota, then heads east through northern Wisconsin, Marquette, Michigan, and then trends more northeasterly to skim the northern-most shores of lakes Michigan and Huron before ending in the Sudbury, Ontario, Canada, area.During the Late Archean Era the Algoman orogeny added landmass to the Superior province by volcanic activity and continental collision along a boundary that stretches from present-day South Dakota, U.S., into the Lake Huron region near Sudbury, Ontario, Canada.This crustal boundary is the Great Lakes tectonic zone. It is 1,400 km (870 mi) long, and separates the older Archean gneissic terrane to the south from younger Late Archean greenstone-granite terrane to the north.The zone is characterized by active compression during the Algoman orogeny (about 2,700 million years ago), a pulling-apart (extensional) tectonics (2,450 to 2,100 million years ago), a second compression during the Penokean orogeny (1,900 to 1,850 million years ago), a second extension during Middle Proterozoic time (1,600 million years ago) and minor reactivation during Phanerozoic time (the past 500 million years).Collision began along the Great Lakes tectonic zone (GLTZ) with the Algoman mountain-building event and continued for tens of millions of years. During the formation of the GLTZ, the gneissic Minnesota River Valley subprovince was thrust up onto the Superior province's edge as it consumed the Superior province's oceanic crust. Fragmentation of the Kenorland supercontinent began 2,450 million years ago and was completed by 2,100 million years ago. The Wyoming province is the continental landmass that is hypothesized to have rifted away from the southern Superior province portion of Kenorland, before moving rapidly west and docking with the Laurentia supercontinent 1,850 to 1,715 million years ago. Sedimentation from the GLTZ-rifting environment continued into the Penokean orogeny, which is the next major tectonic event in the Great Lakes region. Several earthquakes have been documented in Minnesota, Michigan's Upper Peninsula and Sudbury in the last 120 years along the GLTZ.