physical, chemical, and chronological characteristics of
... of the convecting mantle across a broad transition region. This zone of velocity transition, in general not well resolved, ranges from 200 to perhaps 400 km deep beneath different cratons. The largest craton, the Superior Province of North America, also has the deepest seismically fast root into the ...
... of the convecting mantle across a broad transition region. This zone of velocity transition, in general not well resolved, ranges from 200 to perhaps 400 km deep beneath different cratons. The largest craton, the Superior Province of North America, also has the deepest seismically fast root into the ...
v. sulawesi - Vangorselslist
... Andreason, M.W., A.F. Chatfield, J.A. Curiale, M.V. Filewicz, E.D. Lumadyo et al. (2000)- Exploration in the gravity collapse rifts of the Salayar Basin, Indonesia. AAPG 2000 Ann. Mtg (Abstract only) (Salayar Basin offshore SW Sulawesi (S end Makassar Straits) gravity collapse rift formed in M Creta ...
... Andreason, M.W., A.F. Chatfield, J.A. Curiale, M.V. Filewicz, E.D. Lumadyo et al. (2000)- Exploration in the gravity collapse rifts of the Salayar Basin, Indonesia. AAPG 2000 Ann. Mtg (Abstract only) (Salayar Basin offshore SW Sulawesi (S end Makassar Straits) gravity collapse rift formed in M Creta ...
SOIL MAP OF AFRICA SCALE 1 TO 5000000 Explanatory
... precision, and the few common terms were not used consistently throughout. The first consideration of the Service was, therefore, to promote the production of new soils maps covering entire countries and territories. Very few suggestions were made concerning the choice of units, because it was thoug ...
... precision, and the few common terms were not used consistently throughout. The first consideration of the Service was, therefore, to promote the production of new soils maps covering entire countries and territories. Very few suggestions were made concerning the choice of units, because it was thoug ...
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... This workshop classifies differing styles of southwest Pacific rim gold-copper mineralization in an analysis of hydrothermal ore-forming processes. The magmatic arc geothermal systems in the Philippines are used as active analogues in the evaluation of the characteristics of intrusiverelated ore sys ...
... This workshop classifies differing styles of southwest Pacific rim gold-copper mineralization in an analysis of hydrothermal ore-forming processes. The magmatic arc geothermal systems in the Philippines are used as active analogues in the evaluation of the characteristics of intrusiverelated ore sys ...
GEOLOGY OF THE PURCELL SUPERGROUP SOUTHEASTERN
... The Purcell Supergroup comprises athick accumulation of clastic and carbonaterocks that are interpreted to have been deposited in a large intracratonic basin. The northeastern margin of the hasin is exposed in the northern part of the Fernie west-half sheet. It developed by growth faulting and is ch ...
... The Purcell Supergroup comprises athick accumulation of clastic and carbonaterocks that are interpreted to have been deposited in a large intracratonic basin. The northeastern margin of the hasin is exposed in the northern part of the Fernie west-half sheet. It developed by growth faulting and is ch ...
Workshop Report - Consortium for Ocean Leadership
... As illustrated by the many talks and posters at the meeting, our understanding of the processes of mantle melting, melt aggregation and transport have undergone large advances with the integration of mantle geochemistry and rock physics. There was considerable discussion of the origin and consequenc ...
... As illustrated by the many talks and posters at the meeting, our understanding of the processes of mantle melting, melt aggregation and transport have undergone large advances with the integration of mantle geochemistry and rock physics. There was considerable discussion of the origin and consequenc ...
PDF
... The Ueno Basalts of central Japan comprise a monogenetic volcanic cone complex that was active between 2·76 and 1·34 Ma. Basalts were erupted at more than 14 centers scattered over a region 40 km in diameter. Alkali basalt was erupted first, followed by sub-alkaline basalt. Quasi-concentric expansio ...
... The Ueno Basalts of central Japan comprise a monogenetic volcanic cone complex that was active between 2·76 and 1·34 Ma. Basalts were erupted at more than 14 centers scattered over a region 40 km in diameter. Alkali basalt was erupted first, followed by sub-alkaline basalt. Quasi-concentric expansio ...
2.03 Sampling Mantle Heterogeneity through Oceanic Basalts
... spinel, and plagioclase. Adding or subtracting such elements can change the phase assemblage. Trace elements, on the other hand just replace a few atoms of the major elements in the crystal structures without affecting the phase assemblage significantly. They are essentially blind passengers in many ...
... spinel, and plagioclase. Adding or subtracting such elements can change the phase assemblage. Trace elements, on the other hand just replace a few atoms of the major elements in the crystal structures without affecting the phase assemblage significantly. They are essentially blind passengers in many ...
Three lithospheric transects across the Alps and their forelands
... the “Western” and “Eastern” Alps, corresponding to the western limit of the Austroalpine nappes of the Eastern Alps (mapped as “Apulian Plate north of the Periadriatic Line” in Fig. 1) that runs almost perpendicular across the E-W-strike of the present-day Eastern Alps (Fig. 1). This most important ...
... the “Western” and “Eastern” Alps, corresponding to the western limit of the Austroalpine nappes of the Eastern Alps (mapped as “Apulian Plate north of the Periadriatic Line” in Fig. 1) that runs almost perpendicular across the E-W-strike of the present-day Eastern Alps (Fig. 1). This most important ...
ChemCam results from the Shaler outcrop in Gale crater, Mars
... The ‘‘Shaler’’ outcrop is located at 137.4488°E 4.5905°S (planetocentric), near the location in the Glenelg region where the three distinct terrain types meet. Shaler was first identified in panoramic images from the Rocknest aeolian drift. From this distance (40 m), it stood out as a unique thinly l ...
... The ‘‘Shaler’’ outcrop is located at 137.4488°E 4.5905°S (planetocentric), near the location in the Glenelg region where the three distinct terrain types meet. Shaler was first identified in panoramic images from the Rocknest aeolian drift. From this distance (40 m), it stood out as a unique thinly l ...
Chapter 7
... total melt content in sample 5249 was contained in the larger melt bodies (fig 3.7). In addition to the intergranular melt and deformation microstructures, the intragranular deformation structures were analysed (chapter 4). The creep strength during deformation provided indirect evidence that deform ...
... total melt content in sample 5249 was contained in the larger melt bodies (fig 3.7). In addition to the intergranular melt and deformation microstructures, the intragranular deformation structures were analysed (chapter 4). The creep strength during deformation provided indirect evidence that deform ...
Accuracy of plagioclase compositions from laboratory and Mars
... compositional ranges. This suggests that the linear deconvolution technique models plagioclase compositions as more sodic than median or measured ranges of plagioclase compositions. Here we use the term ‘‘sodic bias’’ to denote this potential modeling effect. Wyatt et al. [2001] suggested that the s ...
... compositional ranges. This suggests that the linear deconvolution technique models plagioclase compositions as more sodic than median or measured ranges of plagioclase compositions. Here we use the term ‘‘sodic bias’’ to denote this potential modeling effect. Wyatt et al. [2001] suggested that the s ...
document - OurEnergyPolicy.org
... (principally Ellenburger Dolomite). Contoured CO2 isograds given in percent contained gas and represents the CO2 source plume which charged Leads 1-8 (blue stippled area)........... 67 Exhibit 3-35 Map summarizes the Mesozoic and Cenozoic distribution of kimberlite, carbonatite and lamproite intru ...
... (principally Ellenburger Dolomite). Contoured CO2 isograds given in percent contained gas and represents the CO2 source plume which charged Leads 1-8 (blue stippled area)........... 67 Exhibit 3-35 Map summarizes the Mesozoic and Cenozoic distribution of kimberlite, carbonatite and lamproite intru ...
Plate dynamics, mantle structure and tectonic evolution of the
... South America plate are characterized by large transform-type fault systems [Molnar and Sykes, 1969]. Based on observations of bathymetric relief and gravity anomalies along the northern and eastern plate boundary, Hess [1933] suggested large relative eastward displacement of the Caribbean region. H ...
... South America plate are characterized by large transform-type fault systems [Molnar and Sykes, 1969]. Based on observations of bathymetric relief and gravity anomalies along the northern and eastern plate boundary, Hess [1933] suggested large relative eastward displacement of the Caribbean region. H ...
Magmatic Apatite: A Powerful, Yet Deceptive
... elongate). Equant apatite is generally defi ned by wellformed crystal faces (FIG. 1), and is often easily recognized by its hexagonal shape. This habit is interpreted to have grown under near-equilibrium conditions. Less commonly, equant apatite occurs with no well-formed crystal faces as an interst ...
... elongate). Equant apatite is generally defi ned by wellformed crystal faces (FIG. 1), and is often easily recognized by its hexagonal shape. This habit is interpreted to have grown under near-equilibrium conditions. Less commonly, equant apatite occurs with no well-formed crystal faces as an interst ...
STRUCTURE AND DEVONIAN STRATIGRAPHY OF
... Sequences of Devonian rocks are advantageously exposed along a unique 40mile-long east-west traverse in the greater Timpahute Range, southeastern Nevada. Study of these rocks casts light upon Devonian paleogeography, the Devonian Antler orogeny, an Upper Devonian cosmolite impact basin, this part of ...
... Sequences of Devonian rocks are advantageously exposed along a unique 40mile-long east-west traverse in the greater Timpahute Range, southeastern Nevada. Study of these rocks casts light upon Devonian paleogeography, the Devonian Antler orogeny, an Upper Devonian cosmolite impact basin, this part of ...
Petroleum Geology and Reservoirs of the Wessex Basin
... They give the impression of lines of relative movement between the intervenig stable regions, and clearly represents a basement influence on the sedimentary layers, probably reactivating earlier features. ...
... They give the impression of lines of relative movement between the intervenig stable regions, and clearly represents a basement influence on the sedimentary layers, probably reactivating earlier features. ...
View - Mid Wales Geology Club
... nearly six hundred letters, and there are many relevant old technical papers about the subject. A splendid book by James Secord, Controversy in Victorian Geology, is a detailed account, widely and meticulously sourced.2 Though twenty five years old, nobody can now work on this subject without Secord ...
... nearly six hundred letters, and there are many relevant old technical papers about the subject. A splendid book by James Secord, Controversy in Victorian Geology, is a detailed account, widely and meticulously sourced.2 Though twenty five years old, nobody can now work on this subject without Secord ...
Crustal thickness anomalies in the North Atlantic Ocean Tingting Wang
... [1] Gravity‐derived crustal thickness models were calculated for the North Atlantic Ocean between 76°N and the Chain Fracture Zone and calibrated using seismically determined crustal thickness. About 7% of the ocean crust is <4 km thick (designated as thin crust), and 58% is 4–7 km thick (normal cru ...
... [1] Gravity‐derived crustal thickness models were calculated for the North Atlantic Ocean between 76°N and the Chain Fracture Zone and calibrated using seismically determined crustal thickness. About 7% of the ocean crust is <4 km thick (designated as thin crust), and 58% is 4–7 km thick (normal cru ...
.USGS
... because they because they function function as of unconsolidated unconsolidated sediments sediments compose compose the the surficial surficial aquifer aquifer system. system. The The Two principal Two principal types types of of sediments sediments deposited deposited by by Pleistocene Pleistocene ...
... because they because they function function as of unconsolidated unconsolidated sediments sediments compose compose the the surficial surficial aquifer aquifer system. system. The The Two principal Two principal types types of of sediments sediments deposited deposited by by Pleistocene Pleistocene ...
Adakitic Dacites Formed by Intracrustal Crystal Fractionation of
... contents. An origin by partial melting of high-pressure crustal sources seems unlikely from isotopic and trace element considerations. Mafic enclaves quenched into one of the dacites, on the other hand, constitute plausible parental magmas. Dacites and mafic enclaves share several characteristics su ...
... contents. An origin by partial melting of high-pressure crustal sources seems unlikely from isotopic and trace element considerations. Mafic enclaves quenched into one of the dacites, on the other hand, constitute plausible parental magmas. Dacites and mafic enclaves share several characteristics su ...
The Central Asia collision zone: numerical present-day kinematics
... the western Himalaya and Tibetan Plateau, Tian Shan and Altai Range, and it shallows to ~230 km depth below the southern Tarim Basin and to ~170 km below the Junggar region. The north-eastern Tibetan Plateau is underlined by a thinner lithosphere (LAB depth at ~120 km) with respect to its southern s ...
... the western Himalaya and Tibetan Plateau, Tian Shan and Altai Range, and it shallows to ~230 km depth below the southern Tarim Basin and to ~170 km below the Junggar region. The north-eastern Tibetan Plateau is underlined by a thinner lithosphere (LAB depth at ~120 km) with respect to its southern s ...
state of knowledge of the geothermal provinces of the
... tectonic movements in the last 25-30 Ma. Adolei basalts characterize the first rupture movement within the Arabo-Nubian block which occurred during the later Miocene period (Figure 1). During these first movements the area is under an Ethiopian rift tectonic pattern with N-S extension faults system ...
... tectonic movements in the last 25-30 Ma. Adolei basalts characterize the first rupture movement within the Arabo-Nubian block which occurred during the later Miocene period (Figure 1). During these first movements the area is under an Ethiopian rift tectonic pattern with N-S extension faults system ...
u series disequilibria: insights into mantle melting and
... extent of disequilibrium and the precision of the measurements. For example, if 230Th-238U disequilibrium is measured in a sample (i.e., activity of 230Th does not equal activity of 238U), then this indicates that an event that chemically fractionated U from Th took place less than 380 kyr ago as th ...
... extent of disequilibrium and the precision of the measurements. For example, if 230Th-238U disequilibrium is measured in a sample (i.e., activity of 230Th does not equal activity of 238U), then this indicates that an event that chemically fractionated U from Th took place less than 380 kyr ago as th ...
Crystal Fractionation processes at Baru Volcano from the Deep to
... lower temperature and higher water content [Bachmann et al., 2002]. Most studies in these terranes have concluded that the intercumulus crystallization of amphibole from hydrous magmas has controlled the compositions of derivative liquids until the onset of plagioclase crystallization [Jan and Howie ...
... lower temperature and higher water content [Bachmann et al., 2002]. Most studies in these terranes have concluded that the intercumulus crystallization of amphibole from hydrous magmas has controlled the compositions of derivative liquids until the onset of plagioclase crystallization [Jan and Howie ...
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.