Tectonic Setting and Regional Geology of the KSZ
... the metasediments in the southern sector of the shear zone indicate metamorphic conditions of c. 700° C and 20 km crustal depth. In the northern part of the KSZ lithologies preserve most of their primary compositions, textures and structures. Sedimentary structures and textures (cross and graded bed ...
... the metasediments in the southern sector of the shear zone indicate metamorphic conditions of c. 700° C and 20 km crustal depth. In the northern part of the KSZ lithologies preserve most of their primary compositions, textures and structures. Sedimentary structures and textures (cross and graded bed ...
geology of the virginia city quadrangle
... monitor. All samples except sanidine and alunite were heated incrementally in a low-blank, resistance furnace, generally in ten to twelve 8-minute increments between about 700°C and 1650°C. Individual sanidine grains were fused with a CO2 laser. Alunite was heated incrementally with the CO2 laser us ...
... monitor. All samples except sanidine and alunite were heated incrementally in a low-blank, resistance furnace, generally in ten to twelve 8-minute increments between about 700°C and 1650°C. Individual sanidine grains were fused with a CO2 laser. Alunite was heated incrementally with the CO2 laser us ...
The East African rift system - Department of Earth and Planetary
... This overview paper considers the East African rift system (EARS) as an intra-continental ridge system, comprising an axial rift. It describes the structural organization in three branches, the overall morphology, lithospheric cross-sections, the morphotectonics, the main tectonic features—with emph ...
... This overview paper considers the East African rift system (EARS) as an intra-continental ridge system, comprising an axial rift. It describes the structural organization in three branches, the overall morphology, lithospheric cross-sections, the morphotectonics, the main tectonic features—with emph ...
GSA TODAY - Geological Society of America
... The three concepts have quite different implications for details of tectonic history. For example, models 1 and 3 both involve varieties of so-called supra–subduction-zone ophiolite forming the floors of interarc basins, whereas model 2 envisions only “normal” seafloor spreading in an open ocean bas ...
... The three concepts have quite different implications for details of tectonic history. For example, models 1 and 3 both involve varieties of so-called supra–subduction-zone ophiolite forming the floors of interarc basins, whereas model 2 envisions only “normal” seafloor spreading in an open ocean bas ...
Metamorphic Intro
... – Lag time between the creation of the magma at depth during T maximum, and its migration to the lower grade rocks above – Plutonism may reflect a separate phase of postorogenic collapse magmatism ...
... – Lag time between the creation of the magma at depth during T maximum, and its migration to the lower grade rocks above – Plutonism may reflect a separate phase of postorogenic collapse magmatism ...
McLelland, JM, Selleck, BW, and Bickford, ME, 2010
... between its various components and their plate-tectonic evolution. In recent years, an expanding database derived from modern geophysics, petrology, tectonics, numerical modeling, field investigations, and geochronology has led to substantial clarification of these issues. Most geochronological stud ...
... between its various components and their plate-tectonic evolution. In recent years, an expanding database derived from modern geophysics, petrology, tectonics, numerical modeling, field investigations, and geochronology has led to substantial clarification of these issues. Most geochronological stud ...
Makhtesh Ramon Geological Window, hyper
... Upper Jurassic, 1600 m long and 750 m wide (Fig. 68). 20. The Ramon tectonic lineament. The Ramon anticline is bounded along its SE flank by a complex regional fault system (Fig. 55), which drew the attention of many researchers. 21. The Karney Ramon volcanic basanite complex (Lower Cretaceous) at t ...
... Upper Jurassic, 1600 m long and 750 m wide (Fig. 68). 20. The Ramon tectonic lineament. The Ramon anticline is bounded along its SE flank by a complex regional fault system (Fig. 55), which drew the attention of many researchers. 21. The Karney Ramon volcanic basanite complex (Lower Cretaceous) at t ...
Chapter 11 Notes
... Strike-Slip Faults • In a strike-slip fault, the rock on either side of the fault plane slides horizontally in response to shear stress. ...
... Strike-Slip Faults • In a strike-slip fault, the rock on either side of the fault plane slides horizontally in response to shear stress. ...
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... with direct interaction between the magmas or incorporation of enclaves into the crustal melt, with diffusion across contacts, and phenocryst transfer between mafic and felsic magmas. In addition to interacting, such melts can evolve independently as well. Dehydration melting of crustal sources is co ...
... with direct interaction between the magmas or incorporation of enclaves into the crustal melt, with diffusion across contacts, and phenocryst transfer between mafic and felsic magmas. In addition to interacting, such melts can evolve independently as well. Dehydration melting of crustal sources is co ...
Section 1 What Are Earthquakes?
... of the 20th century, seismologists used a scale created by Charles Richter to measure the strength of earthquakes. • Earthquake Ground Motion A measure of the strength of an earthquake is called magnitude. The Richter scale measures the ground motion from an earthquake and adjusts for distance to fi ...
... of the 20th century, seismologists used a scale created by Charles Richter to measure the strength of earthquakes. • Earthquake Ground Motion A measure of the strength of an earthquake is called magnitude. The Richter scale measures the ground motion from an earthquake and adjusts for distance to fi ...
KoreaTaejonLetters
... aftershocks, would happen near the area where the quite considerable earthquakes had happened. Also, other coming earthquakes would also be near the recent earthquakes, because interaction of plates (pieces of outer layer of crust) causes stress. So, almost all of the earthquakes happen near plate b ...
... aftershocks, would happen near the area where the quite considerable earthquakes had happened. Also, other coming earthquakes would also be near the recent earthquakes, because interaction of plates (pieces of outer layer of crust) causes stress. So, almost all of the earthquakes happen near plate b ...
Interpretation of an Aeromagnetic Survey of the Amchitka Island
... the steeper gradients of theoretical anomalies a r e positioned near the ends of flows or sills that have been terminated by faulting. Drill sites were selected in areas away from gradients considered to be fault related. Nearly all prominent anomalies over land and many over water can be reasonably ...
... the steeper gradients of theoretical anomalies a r e positioned near the ends of flows or sills that have been terminated by faulting. Drill sites were selected in areas away from gradients considered to be fault related. Nearly all prominent anomalies over land and many over water can be reasonably ...
Geological Society of America Bulletin - UCLA
... plain the low-angle domal and basinal detachment-fault geometry, each predicting a specific geologic relationship between the detachment fault and the structures above and below it. Most workers concluded that the domal and basinal detachment-fault geometry is related to superposition of two mechani ...
... plain the low-angle domal and basinal detachment-fault geometry, each predicting a specific geologic relationship between the detachment fault and the structures above and below it. Most workers concluded that the domal and basinal detachment-fault geometry is related to superposition of two mechani ...
Geomorphic analysis of transient landscapes in the Sierra
... Correa-Mora et al., 2009). Using GPS data (Fig. 3b), LyonCaen et al. (2006) proposed a model of the plate boundary which took into account both the extensional province and the forearc sliver. They suggested that the eastward escape of the Caribbean Plate was accommodated by dextral slip along the J ...
... Correa-Mora et al., 2009). Using GPS data (Fig. 3b), LyonCaen et al. (2006) proposed a model of the plate boundary which took into account both the extensional province and the forearc sliver. They suggested that the eastward escape of the Caribbean Plate was accommodated by dextral slip along the J ...
Cenozoic tectonic evolution in the Central Andes in northern Chile
... multidisciplinary groups working in that region. In this article, we synthesize available stratigraphic, sedimentologic, structural, and chronologic evidence for the late Paleogene to present evolution on both sides of the Andes in northern Chile, southern Peru, western Bolivia and northwestern Arge ...
... multidisciplinary groups working in that region. In this article, we synthesize available stratigraphic, sedimentologic, structural, and chronologic evidence for the late Paleogene to present evolution on both sides of the Andes in northern Chile, southern Peru, western Bolivia and northwestern Arge ...
Unit 1 The Ocean Basins
... According to fossil and rock records, oceans have existed on Earth for at least 3.8 billion years. It is easy to think that they are permanent features, ancient and unchanging. However, the only thing that is truly constant about ocean basins — and continents — is that they are always moving and cha ...
... According to fossil and rock records, oceans have existed on Earth for at least 3.8 billion years. It is easy to think that they are permanent features, ancient and unchanging. However, the only thing that is truly constant about ocean basins — and continents — is that they are always moving and cha ...
The life cycle of suprasubduction zone ophiolites
... active spreading and ophiolite-related volcanism, which in many (but not all) cases is linked to collision with an active spreading center, and its partial or complete subduction by the over-riding plate (Figure 2d); 5. Resurrection, which is the emplacement of the ophiolite onto a passive continent ...
... active spreading and ophiolite-related volcanism, which in many (but not all) cases is linked to collision with an active spreading center, and its partial or complete subduction by the over-riding plate (Figure 2d); 5. Resurrection, which is the emplacement of the ophiolite onto a passive continent ...
the complex tectonic events and their influence on formation
... 1500-1700 m a.s.l. spread along the Da River from the Chinese border to the South China Sea coast. Narrow canyons or very deep river valleys separate the plateaus and ridges. These Sin Chai, Son La, and Moc Chau plateaus are made up by Devonian and Triassic limestones. They contain spectacular areas ...
... 1500-1700 m a.s.l. spread along the Da River from the Chinese border to the South China Sea coast. Narrow canyons or very deep river valleys separate the plateaus and ridges. These Sin Chai, Son La, and Moc Chau plateaus are made up by Devonian and Triassic limestones. They contain spectacular areas ...
geologic time, concepts, and principles
... Gould argued that Hutton's interpretation of uniformitarianism actually included a cyclical series of events in which all of Earth history was repeated with "repair" of the earlier age, much as many primal societies view time as a cyclical, rather than linear, phenomenon. Furthermore, the rates of g ...
... Gould argued that Hutton's interpretation of uniformitarianism actually included a cyclical series of events in which all of Earth history was repeated with "repair" of the earlier age, much as many primal societies view time as a cyclical, rather than linear, phenomenon. Furthermore, the rates of g ...
Shervais, J.W., 2001, Birth, Death, and Resurrection: The Life Cycle
... active spreading and ophiolite-related volcanism, which in many (but not all) cases is linked to collision with an active spreading center, and its partial or complete subduction by the over-riding plate (Figure 2d); 5. Resurrection, which is the emplacement of the ophiolite onto a passive continent ...
... active spreading and ophiolite-related volcanism, which in many (but not all) cases is linked to collision with an active spreading center, and its partial or complete subduction by the over-riding plate (Figure 2d); 5. Resurrection, which is the emplacement of the ophiolite onto a passive continent ...
New Hypothesis for the Formation of the Catalina
... believed by some to also represent a product of Middle Jurassic nascent subduction (e.g., Stern and Bloomer, 1992). Although the nascent subduction model may generally explain the genesis of Middle Jurassic high-grade rocks within the Franciscan Complex, initiation of a new subduction zone off the ...
... believed by some to also represent a product of Middle Jurassic nascent subduction (e.g., Stern and Bloomer, 1992). Although the nascent subduction model may generally explain the genesis of Middle Jurassic high-grade rocks within the Franciscan Complex, initiation of a new subduction zone off the ...
alleghanian plutonism in the eastern blue ridge
... Historically, researchers believed that Alleghanian magmatism occurred during or after continental collision without any subduction-induced melting (Price 1969, Speer et al. 1994, Samson et al. 1995a, Hatcher 2005). With the exception of the EBR plutons - which predate the 330 Ma estimated collision ...
... Historically, researchers believed that Alleghanian magmatism occurred during or after continental collision without any subduction-induced melting (Price 1969, Speer et al. 1994, Samson et al. 1995a, Hatcher 2005). With the exception of the EBR plutons - which predate the 330 Ma estimated collision ...
BANDED GNEISSES OF EIGHT LOCALITIES G eneral S tatemen t.
... The "banded diorite of Helsinki" consists of alternating bands of amphibolites, amphibole gneisses, granodioritic-composition gneisses, granitic-composition gneisses, impure quartzites, and metagraywackes. There is evidence of local mobilization (possibly tectonic), injection, and mineralogical chan ...
... The "banded diorite of Helsinki" consists of alternating bands of amphibolites, amphibole gneisses, granodioritic-composition gneisses, granitic-composition gneisses, impure quartzites, and metagraywackes. There is evidence of local mobilization (possibly tectonic), injection, and mineralogical chan ...
Large igneous province
A large igneous province (LIP) is an extremely large accumulation of igneous rocks, including liquid rock (intrusive) or volcanic rock formations (extrusive), when hot magma extrudes from inside the Earth and flows out. The source of many or all LIPs is variously attributed to mantle plumes or to processes associated with plate tectonics. Types of LIPs can include large volcanic provinces (LVP), created through flood basalt and large plutonic provinces (LPP). Eleven distinct flood basalt episodes occurred in the past 250 million years, creating volcanic provinces, which coincided with mass extinctions in prehistoric times. Formation depends on a range of factors, such as continental configuration, latitude, volume, rate, duration of eruption, style and setting (continental vs. oceanic), the preexisting climate state, and the biota resilience to change.