Provenance and correlation of sediments in Telemark, South Norway
... area is structurally complex, including several Precambrian fault- and shear zones that strike in a general N-S direction and that subdivide the area into several structural domains (Fig. 1). In the literature, the Precambrian bedrock areas bordered by these fault and shear zones have been called se ...
... area is structurally complex, including several Precambrian fault- and shear zones that strike in a general N-S direction and that subdivide the area into several structural domains (Fig. 1). In the literature, the Precambrian bedrock areas bordered by these fault and shear zones have been called se ...
Origin of the concentrated deformation zone in the Japanese Islands... accumulation process of intraplate earthquakes
... that the plastic flow is uniformly distributed below the seismogenic zone. However, they found that the cut-off depth could be attributed to the transition depth if the strain rate is greater than 10−13 /s, indicating that deformation should be localized in a narrow fault zone below the seismogenic ...
... that the plastic flow is uniformly distributed below the seismogenic zone. However, they found that the cut-off depth could be attributed to the transition depth if the strain rate is greater than 10−13 /s, indicating that deformation should be localized in a narrow fault zone below the seismogenic ...
3.20 Trace Element and Isotopic Fluxes
... diagenesis (and for mafic rocks, possibly hydration). Discussion of the metamorphic record is focused primarily on HP and UHP suites in the circum-Pacific, Cyclades, and European Alps, which have seen the most geochemical study focused on issues of ocean-to-mantle cycling. This review is meant to comp ...
... diagenesis (and for mafic rocks, possibly hydration). Discussion of the metamorphic record is focused primarily on HP and UHP suites in the circum-Pacific, Cyclades, and European Alps, which have seen the most geochemical study focused on issues of ocean-to-mantle cycling. This review is meant to comp ...
Papers presented to the Conference on Heat and Detachment in
... on the Sonora-Arizona border. Deformed rocks do not crop out continuously within this band but occur as domains segmented by sharp or transitional boundaries. In northern Sonora extensive outcrops of Tgn-s exist between the Mojave-Sonora megashear and a series of straight, northwesterly-trending lin ...
... on the Sonora-Arizona border. Deformed rocks do not crop out continuously within this band but occur as domains segmented by sharp or transitional boundaries. In northern Sonora extensive outcrops of Tgn-s exist between the Mojave-Sonora megashear and a series of straight, northwesterly-trending lin ...
The strength of faults in the crust in the western
... and T is temperature. In the model frictional sliding and dislocation creep compete at faults: friction dominates in the upper part, where the normal force is small, while dislocation creep dominates at depth, where the temperature is high enough to achieve substantial sliprates. The depth of the tr ...
... and T is temperature. In the model frictional sliding and dislocation creep compete at faults: friction dominates in the upper part, where the normal force is small, while dislocation creep dominates at depth, where the temperature is high enough to achieve substantial sliprates. The depth of the tr ...
Basaltic and Gabbroic Rocks
... 1. Oceanic Ridges - these are the oceanic spreading centers where a relatively small range of chemical compositions of basalts are erupted to form the basaltic layer of the oceanic crust. This chemical type of basalt is referred to as Mid Ocean Ridge Basalts (MORBs). In some areas, particularly Icel ...
... 1. Oceanic Ridges - these are the oceanic spreading centers where a relatively small range of chemical compositions of basalts are erupted to form the basaltic layer of the oceanic crust. This chemical type of basalt is referred to as Mid Ocean Ridge Basalts (MORBs). In some areas, particularly Icel ...
glossary of terms in engineering geology
... Coarse-grained sedimentary rock composed of rounded to subangular fragments larger than 2mm average dimension set in a sand or finer-grained matrix which is often cemented. (Contrast with "sedimentary breccia"). ...
... Coarse-grained sedimentary rock composed of rounded to subangular fragments larger than 2mm average dimension set in a sand or finer-grained matrix which is often cemented. (Contrast with "sedimentary breccia"). ...
New data on the deposition age of the volcano
... deposited in a widespread epicratonic basin that extends to southern of the Lubango region in SW of Angola. The basement rocks of the Chela Group integrate the Eburnean belt, consisting mainly of gneisses and migmatites, syntectonic foliated peraluminous granites, and late-tectonic metaluminous gran ...
... deposited in a widespread epicratonic basin that extends to southern of the Lubango region in SW of Angola. The basement rocks of the Chela Group integrate the Eburnean belt, consisting mainly of gneisses and migmatites, syntectonic foliated peraluminous granites, and late-tectonic metaluminous gran ...
Geological characteristics of hydrocarbon reservoirs
... The reservoir rock, which is porous and permeable, contains the hydrocarbons; determining the nature of this rock and its geometry is the goal of hydrocarbon exploration. The boundaries of the rock may coincide with the actual accumulation of hydrocarbons, although the latter are usually concentrate ...
... The reservoir rock, which is porous and permeable, contains the hydrocarbons; determining the nature of this rock and its geometry is the goal of hydrocarbon exploration. The boundaries of the rock may coincide with the actual accumulation of hydrocarbons, although the latter are usually concentrate ...
the origin of the strjugsskarð andesite, skagi peninsula, north
... Petrography & Electron Microprobe Analysis The megacrysts of all samples show a wide range of degree of sieve texturing and the edges are usually rough and ragged, indicating disequilibrium (Fig. 3). Some megacrysts have a coarser matrix thinly surrounding the crystal, suggesting a mixing origin for ...
... Petrography & Electron Microprobe Analysis The megacrysts of all samples show a wide range of degree of sieve texturing and the edges are usually rough and ragged, indicating disequilibrium (Fig. 3). Some megacrysts have a coarser matrix thinly surrounding the crystal, suggesting a mixing origin for ...
Volcanic Activity
... So viscosity, and hence the violence of eruptions, is determined by composition, but what controls composition? Volcanic activity is linked to the plate tectonic cycle with mild eruptions occurring in plate interiors and along oceanic ridges, and more violent eruptions associated with convergent pla ...
... So viscosity, and hence the violence of eruptions, is determined by composition, but what controls composition? Volcanic activity is linked to the plate tectonic cycle with mild eruptions occurring in plate interiors and along oceanic ridges, and more violent eruptions associated with convergent pla ...
An Overview of the Structure and Evolution of the Ouachita Orogenic
... of the colliding terranes but caused modest foreland deformation. The converse seems true for the Ouachita and Variscan (?) orogenies. The Ancestral Rocky Mountains orogeny that is best documented along the Wichita-Amarillo uplift is a puzzling case of major intraplate deformation. There are many po ...
... of the colliding terranes but caused modest foreland deformation. The converse seems true for the Ouachita and Variscan (?) orogenies. The Ancestral Rocky Mountains orogeny that is best documented along the Wichita-Amarillo uplift is a puzzling case of major intraplate deformation. There are many po ...
Empplacement Of The Bibai And Gogai Nappes, Northeast Of Quetta
... nappe suggesl that these rocks were deposited on the continental slope while the same foxmation is well bedded at the base of Bibai nappe indicating deposition on continental shelf. All these observations indicate that a considerable tectonic transport was involved in the emplacement of Gogai nappe ...
... nappe suggesl that these rocks were deposited on the continental slope while the same foxmation is well bedded at the base of Bibai nappe indicating deposition on continental shelf. All these observations indicate that a considerable tectonic transport was involved in the emplacement of Gogai nappe ...
Geology of the Gorny Altai subduction–accretion complex, southern
... plate tectonic framework since Dewey and Bird (1970). The former, also called Pacific-type (Matsuda and Uyeda, 1971) or Miyashiro-type (Maruyama, 1997), sis characterized by the formation of subduction–accretion complexes involving high-P/T metamorphic (HP) rocks, and extensive calc-alkaline magmatis ...
... plate tectonic framework since Dewey and Bird (1970). The former, also called Pacific-type (Matsuda and Uyeda, 1971) or Miyashiro-type (Maruyama, 1997), sis characterized by the formation of subduction–accretion complexes involving high-P/T metamorphic (HP) rocks, and extensive calc-alkaline magmatis ...
Lecture10 File
... Surface features: Maps showing global topography of the Earth show that elevations fall into two main areas (see next page). The oceans are generally low in elevation whilst the continents are higher in elevation. The reason for this is that the crust has a different composition and thickness in the ...
... Surface features: Maps showing global topography of the Earth show that elevations fall into two main areas (see next page). The oceans are generally low in elevation whilst the continents are higher in elevation. The reason for this is that the crust has a different composition and thickness in the ...
Ore Bin / Oregon Geology magazine / journal
... en echelon faults. It extends across central Oregon on a general N. 75° W. course from the Harney Basin to Newberry Volcano, a distance of more than 100 miles. Along its southern margin, the large north-south faults that define Steens Mountain, Abert Rim, and other young fault blocks of the Basin an ...
... en echelon faults. It extends across central Oregon on a general N. 75° W. course from the Harney Basin to Newberry Volcano, a distance of more than 100 miles. Along its southern margin, the large north-south faults that define Steens Mountain, Abert Rim, and other young fault blocks of the Basin an ...
The Earth
... 4.0 The properties of rocks and minerals reflect the processes that formed them. As a basis for understanding this concept: a. Students know how to differentiate among igneous, sedimentary, and metamorphic rocks by referring to their properties and methods of formation (the rock cycle). b. Students ...
... 4.0 The properties of rocks and minerals reflect the processes that formed them. As a basis for understanding this concept: a. Students know how to differentiate among igneous, sedimentary, and metamorphic rocks by referring to their properties and methods of formation (the rock cycle). b. Students ...
The global range of subduction zone thermal structures from
... The assumption of full coupling of subducting slab and convecting overlying mantle at 80 km depth with no mantle convection at shallower levels results in a “shelf” in the P–T paths at 80 km (between ∼2 and 2.5 GPa) in which there is an isobaric temperature increase. An average D80 P–T path was calc ...
... The assumption of full coupling of subducting slab and convecting overlying mantle at 80 km depth with no mantle convection at shallower levels results in a “shelf” in the P–T paths at 80 km (between ∼2 and 2.5 GPa) in which there is an isobaric temperature increase. An average D80 P–T path was calc ...
Simonson_2003.pdf
... determined from strain analysis; b.) Shapes of feldspar grains measured in threedimensional feldspar strain analysis……………………………………………………..80 ...
... determined from strain analysis; b.) Shapes of feldspar grains measured in threedimensional feldspar strain analysis……………………………………………………..80 ...
clay, mudstone, shale and slate
... or red mudstones and shales may contain oxidized ferric iron minerals such as hematite (Fe2O3). Organic-rich shales are dark-grey or black, whereas pale-grey, pale-green or white mudstones may have a high content of one type of clay mineral (e.g. bentonite). Minute brassy crystals are usually pyrite ...
... or red mudstones and shales may contain oxidized ferric iron minerals such as hematite (Fe2O3). Organic-rich shales are dark-grey or black, whereas pale-grey, pale-green or white mudstones may have a high content of one type of clay mineral (e.g. bentonite). Minute brassy crystals are usually pyrite ...
Tectonic controls on the distribution of large
... below thin crust of SE Asia. The oblique vector of this subduction results in the formation of an important dextral shear zone on Sumatra, the Sumatran Fault Zone. No significant porphyry systems are known in western Indonesia. The subducting oceanic plate in this region comprises cold Eocene crust, ...
... below thin crust of SE Asia. The oblique vector of this subduction results in the formation of an important dextral shear zone on Sumatra, the Sumatran Fault Zone. No significant porphyry systems are known in western Indonesia. The subducting oceanic plate in this region comprises cold Eocene crust, ...
Shock metamorphism of siliceous volcanic rocks of the El`gygytgyn
... (1983), and Gurov and Yamnichenko (1995). The crater is surrounded by an uplifted rim that has an asymmetrical cross section, with steep inner walls and gentle outer slopes. The average height of the rim, ~180 m above the lake level and 140 m above the surrounding area, was calculated from 24 radial ...
... (1983), and Gurov and Yamnichenko (1995). The crater is surrounded by an uplifted rim that has an asymmetrical cross section, with steep inner walls and gentle outer slopes. The average height of the rim, ~180 m above the lake level and 140 m above the surrounding area, was calculated from 24 radial ...
SGES 1302 Lecture3
... Since the average density of surface material is only around 3000 kg/m3, we must conclude that denser materials exist within Earth's core. Further evidence for the high density core comes from the study of seismology. In its earliest stages, about 4.5 billion years ago, melting would have caused den ...
... Since the average density of surface material is only around 3000 kg/m3, we must conclude that denser materials exist within Earth's core. Further evidence for the high density core comes from the study of seismology. In its earliest stages, about 4.5 billion years ago, melting would have caused den ...
4. Structure of the Peru Forearc from Multichannel Seismic
... axis is approximately 2 km wide on line 14, but ranges up to 3 km wide on other Lima Basin seismic lines. A 400- to 500-mthick wedge of trench fill sediments overlies and onlaps the underlying hemipelagic sediments. The horizontally stratified, laterally continuous nature of the trench strata sugges ...
... axis is approximately 2 km wide on line 14, but ranges up to 3 km wide on other Lima Basin seismic lines. A 400- to 500-mthick wedge of trench fill sediments overlies and onlaps the underlying hemipelagic sediments. The horizontally stratified, laterally continuous nature of the trench strata sugges ...
How Old Is It? How Do We Know? A Review of Dating Methods
... The principle of original horizontality takes its clue from the observation that modern sediment layers, with exceptions such as the dipping sand layers in dunes and sediments that accumulate on moderate slopes, are commonly deposited very close to the horizontal. In applying this principle to layer ...
... The principle of original horizontality takes its clue from the observation that modern sediment layers, with exceptions such as the dipping sand layers in dunes and sediments that accumulate on moderate slopes, are commonly deposited very close to the horizontal. In applying this principle to layer ...
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.