Geomorphic constraints on fault throw rates and linkage times
... The active tectonic and geodynamic setting of Greece has been widely reviewed [e.g., Billiris et al., 1991; Clarke et al., 1998; Davies et al., 1997; Hollenstein et al., 2008; Roberts and Jackson, 1991; Le Pichon and Angelier, 1979; Jackson, 1994], so only a brief summary is given here. Seismicity a ...
... The active tectonic and geodynamic setting of Greece has been widely reviewed [e.g., Billiris et al., 1991; Clarke et al., 1998; Davies et al., 1997; Hollenstein et al., 2008; Roberts and Jackson, 1991; Le Pichon and Angelier, 1979; Jackson, 1994], so only a brief summary is given here. Seismicity a ...
Possible density segregation of subducted oceanic
... a dip angle of 60°, common for most modern subduction zones [34], such a slab would surely have entered the mantle transition zone or even possibly the lower mantle. Thus, if serpentinization can extend ∼ 20–30 km into the oceanic lithosphere, a hydrated zone, made up of serpentine (at low pressure) ...
... a dip angle of 60°, common for most modern subduction zones [34], such a slab would surely have entered the mantle transition zone or even possibly the lower mantle. Thus, if serpentinization can extend ∼ 20–30 km into the oceanic lithosphere, a hydrated zone, made up of serpentine (at low pressure) ...
Incipient shortening of a passive margin: the mechanical roles of
... Key words: analogue modelling, incipient shortening, obduction, passive margin, post-breakup, strength profiles, subduction. ...
... Key words: analogue modelling, incipient shortening, obduction, passive margin, post-breakup, strength profiles, subduction. ...
Physics and Chemistry of Deep Continental Crust
... margins. Examples include epirogenic uplift (e.g., the Colorado Plateau in southwestern United States and the Hangay Dome in Mongolia, both far from plate boundaries) as well as the magmatism and enhanced surface heat flow often associated with these anomalous uplifts. Bird (1979) may have been the ...
... margins. Examples include epirogenic uplift (e.g., the Colorado Plateau in southwestern United States and the Hangay Dome in Mongolia, both far from plate boundaries) as well as the magmatism and enhanced surface heat flow often associated with these anomalous uplifts. Bird (1979) may have been the ...
Origin of Archean subcontinental lithospheric mantle: Some
... crustal portion is also stratified, from gabbros and Fe-rich olivinepyroxene cumulates in the lower part, to basalt in the upper part. The fraction of harzburgite and dunite is low (b10%) and material with the composition of Fe-poor cratonic peridotite is absent. In modern lithosphere, the proportion ...
... crustal portion is also stratified, from gabbros and Fe-rich olivinepyroxene cumulates in the lower part, to basalt in the upper part. The fraction of harzburgite and dunite is low (b10%) and material with the composition of Fe-poor cratonic peridotite is absent. In modern lithosphere, the proportion ...
Moho and magmatic underplating
... regions. Clearly, plate boundary processes, at both subduction and rift zones, play major roles in the shaping of the continental crust by tectonic and magmatic processes. These processes and their importance for forming the continental lithosphere have been widely discussed with focus on the variou ...
... regions. Clearly, plate boundary processes, at both subduction and rift zones, play major roles in the shaping of the continental crust by tectonic and magmatic processes. These processes and their importance for forming the continental lithosphere have been widely discussed with focus on the variou ...
univERsity oF copEnhAGEn
... regions. Clearly, plate boundary processes, at both subduction and rift zones, play major roles in the shaping of the continental crust by tectonic and magmatic processes. These processes and their importance for forming the continental lithosphere have been widely discussed with focus on the variou ...
... regions. Clearly, plate boundary processes, at both subduction and rift zones, play major roles in the shaping of the continental crust by tectonic and magmatic processes. These processes and their importance for forming the continental lithosphere have been widely discussed with focus on the variou ...
GEOLOGIC STRUCTURE OF THE UPPERMOST OCEANIC CRUST
... intermediate- to fast-spreading ridges, which are commonly perceived as the simplest types of spreading centers—ones that are likely to conform to traditional models and to generate a geologically simple layered crust. The details of the geology of a few key areas have been accumulating over the pas ...
... intermediate- to fast-spreading ridges, which are commonly perceived as the simplest types of spreading centers—ones that are likely to conform to traditional models and to generate a geologically simple layered crust. The details of the geology of a few key areas have been accumulating over the pas ...
TROPICS Continent-Building in Costa Rica
... Southern Central America - and especially Costa Rica - is a region of thick crust of oceanic origin that is undergoing both subduction and underthrusting and that is also developing features characteristic of continents, including the emplacement of arc magmas that are unusually similar in compositi ...
... Southern Central America - and especially Costa Rica - is a region of thick crust of oceanic origin that is undergoing both subduction and underthrusting and that is also developing features characteristic of continents, including the emplacement of arc magmas that are unusually similar in compositi ...
Rudnick and Lee.fm - Cin
... replacement by upwelling convecting mantle that cooled against the surrounding lithosphere. The timing of this replacement is not well constrained by Os systematics, but probably occurred during development of the Mesozoic arc. A second deep lithosphere removal event is suggested by the presence of ...
... replacement by upwelling convecting mantle that cooled against the surrounding lithosphere. The timing of this replacement is not well constrained by Os systematics, but probably occurred during development of the Mesozoic arc. A second deep lithosphere removal event is suggested by the presence of ...
mantle plumes and hot spots - The Centre for Earth Evolution and
... is underlain by a broad upwelling or that widespread flow from a plume is occurring beneath the lithosphere, with locations of volcanism controlled by lithospheric stresses. Geometry and radiometric age data of hotspot tracks indicate that the relative motion of hotspots is typically slow compared t ...
... is underlain by a broad upwelling or that widespread flow from a plume is occurring beneath the lithosphere, with locations of volcanism controlled by lithospheric stresses. Geometry and radiometric age data of hotspot tracks indicate that the relative motion of hotspots is typically slow compared t ...
Use of Hydrothermal Mineralogy and Geological Structures in
... Stage 2; the trachyte eruption was followed by the caldera collapse forming a depression 11 km x 7.5 km across (Clarke et al., 1990). The collapse is evidenced by the presence of a ring of rhyolite domes inferred to have intruded along a ring fault. Further evidence of collapse includes pyroclastic ...
... Stage 2; the trachyte eruption was followed by the caldera collapse forming a depression 11 km x 7.5 km across (Clarke et al., 1990). The collapse is evidenced by the presence of a ring of rhyolite domes inferred to have intruded along a ring fault. Further evidence of collapse includes pyroclastic ...
Geodynamic models of Cordilleran orogens
... The central Andes represents the type example of a Cordilleran orogen, in which crustal shortening has produced a continental mountain belt above an active subduction zone. Geological studies indicate that the central Andes was primarily built through 200 to >500 km of shortening of the western Sout ...
... The central Andes represents the type example of a Cordilleran orogen, in which crustal shortening has produced a continental mountain belt above an active subduction zone. Geological studies indicate that the central Andes was primarily built through 200 to >500 km of shortening of the western Sout ...
eastern european alpine system and the carpathian
... mountain terranes their internal structural development is conspicuously diachronous and is dependent upon the relative motion of at least three fragments of continental crust which lay between the European and African plate. In Late Jurassic time the three fragments of continental crust were separa ...
... mountain terranes their internal structural development is conspicuously diachronous and is dependent upon the relative motion of at least three fragments of continental crust which lay between the European and African plate. In Late Jurassic time the three fragments of continental crust were separa ...
The origin of Mount St. Helens andesites
... features of representative lavas erupted during the past 2200 years can distinguish three basaltic and three andesitic variants. The mafic lavas include: (a) transitional, olivine + plagioclase basalts with low K2O and incompatible trace-element abundances: (b) calc-alkaline, olivine + plagioclase ± ...
... features of representative lavas erupted during the past 2200 years can distinguish three basaltic and three andesitic variants. The mafic lavas include: (a) transitional, olivine + plagioclase basalts with low K2O and incompatible trace-element abundances: (b) calc-alkaline, olivine + plagioclase ± ...
Rheological heterogeneity, mechanical anisotropy
... the tectonic behaviour of the lithosphere. Lateral rheological heterogeneity of the continental lithosphere may result from various sources, with variations in geothermal gradient being the principal one. The oldest domains of continents, the cratonic nuclei, are characterized by a relatively cold, ...
... the tectonic behaviour of the lithosphere. Lateral rheological heterogeneity of the continental lithosphere may result from various sources, with variations in geothermal gradient being the principal one. The oldest domains of continents, the cratonic nuclei, are characterized by a relatively cold, ...
Roberts et al., 2013, Basin Modeling
... The gravity inversion methodology and workflow is summarized in Figure 1a (adapted from Alvey 2010). Key to the success of the gravity inversion method are two geological corrections, made in order to account for the highly attenuated nature of the continental crust at rifted margins. The two correc ...
... The gravity inversion methodology and workflow is summarized in Figure 1a (adapted from Alvey 2010). Key to the success of the gravity inversion method are two geological corrections, made in order to account for the highly attenuated nature of the continental crust at rifted margins. The two correc ...
Mechanisms of crustal growth in large igneous
... asthenospheric mantle) because of the contamination of the melts by various crustal lithologies as illustrated by the Scottish Tertiary volcanics (e.g., Dickin et al., 1987, among others). Another approach to discuss the origin of the igneous activity is to establish the pattern of magma flow within ...
... asthenospheric mantle) because of the contamination of the melts by various crustal lithologies as illustrated by the Scottish Tertiary volcanics (e.g., Dickin et al., 1987, among others). Another approach to discuss the origin of the igneous activity is to establish the pattern of magma flow within ...
Metamorphic reworking of a high pressure–low temperature
... The Guatemala suture zone is a major east–west left-lateral strike slip boundary that separates the North American and Caribbean plates in Guatemala. The Motagua fault, the central active strand of the suture zone, underwent two major collisional events within a system otherwise dominated by strike– ...
... The Guatemala suture zone is a major east–west left-lateral strike slip boundary that separates the North American and Caribbean plates in Guatemala. The Motagua fault, the central active strand of the suture zone, underwent two major collisional events within a system otherwise dominated by strike– ...
ž / Evidence from mantle xenoliths for relatively thin -100
... Received 6 April 1998; received in revised form 8 February 1999; accepted 9 February 1999 ...
... Received 6 April 1998; received in revised form 8 February 1999; accepted 9 February 1999 ...
Lower crustal earthquakes near the Ethiopian rift induced by
... and are especially concentrated near zones with the largest fraction of partial melt, likely sourced from the mantle. Although magmatism outside the MER rift axis may currently be particularly concentrated near volcanic centers, geophysical data suggest a small fraction of aligned partial melt is wi ...
... and are especially concentrated near zones with the largest fraction of partial melt, likely sourced from the mantle. Although magmatism outside the MER rift axis may currently be particularly concentrated near volcanic centers, geophysical data suggest a small fraction of aligned partial melt is wi ...
Pb composition of Mesozoic Pacific oceanic crust
... are the exclusive occurrence of a 200 m thick volcaniclastic layer in front of the Mariana arc and the restriction of carbonate-rich lithologies in front of the Izu arc. These differences are due to differences in the plate evolution such as the proximity of Site 801 to the Magellan Seamounts, a dom ...
... are the exclusive occurrence of a 200 m thick volcaniclastic layer in front of the Mariana arc and the restriction of carbonate-rich lithologies in front of the Izu arc. These differences are due to differences in the plate evolution such as the proximity of Site 801 to the Magellan Seamounts, a dom ...
The American Cordillera: Part III, The North American Taphrogen
... Campanian—Maastrichtian time. This extension produced no known surface-breaking faults, and may have been restricted to mid-crustal rocks. Coeval with extension in the hinterland region, major thinskinned thrust systems propagated eastward into Wyoming in the frontal Sevier belt. The contemporaneity ...
... Campanian—Maastrichtian time. This extension produced no known surface-breaking faults, and may have been restricted to mid-crustal rocks. Coeval with extension in the hinterland region, major thinskinned thrust systems propagated eastward into Wyoming in the frontal Sevier belt. The contemporaneity ...
A geological model for the structure of ridge segments in slow
... The axes of mid-oceanridges are offset by discontinuities and Laughton, 1977], and adjacentspreadingaxes often overwhich divide the oceancrust into spreadingsegments(Figure lap, with crustal ridges or septa cutting acrossthe discontinu1) [Macdonald et al., 1991]. First-order discontinuities in ities ...
... The axes of mid-oceanridges are offset by discontinuities and Laughton, 1977], and adjacentspreadingaxes often overwhich divide the oceancrust into spreadingsegments(Figure lap, with crustal ridges or septa cutting acrossthe discontinu1) [Macdonald et al., 1991]. First-order discontinuities in ities ...
Metamorphic reworking of a high - Lamont
... The Guatemala suture zone is a major east–west left-lateral strike slip boundary that separates the North American and Caribbean plates in Guatemala. The Motagua fault, the central active strand of the suture zone, underwent two major collisional events within a system otherwise dominated by strike– ...
... The Guatemala suture zone is a major east–west left-lateral strike slip boundary that separates the North American and Caribbean plates in Guatemala. The Motagua fault, the central active strand of the suture zone, underwent two major collisional events within a system otherwise dominated by strike– ...
Northern Cordilleran Volcanic Province
The Northern Cordilleran Volcanic Province (NCVP), formerly known as the Stikine Volcanic Belt, is a geologic province defined by the occurrence of Miocene to Holocene volcanoes in the Pacific Northwest of North America. This belt of volcanoes extends roughly north-northwest from northwestern British Columbia and the Alaska Panhandle through Yukon to the Southeast Fairbanks Census Area of far eastern Alaska, in a corridor hundreds of kilometres wide. It is the most recently defined volcanic province in the Western Cordillera. It has formed due to extensional cracking of the North American continent—similar to other on-land extensional volcanic zones, including the Basin and Range Province and the East African Rift. Although taking its name from the Western Cordillera, this term is a geologic grouping rather than a geographic one. The southmost part of the NCVP has more, and larger, volcanoes than does the rest of the NCVP; further north it is less clearly delineated, describing a large arch that sways westward through central Yukon.At least four large volcanoes are grouped with the Northern Cordilleran Volcanic Province, including Hoodoo Mountain in the Boundary Ranges, the Mount Edziza volcanic complex on the Tahltan Highland, and Level Mountain and Heart Peaks on the Nahlin Plateau. These four volcanoes have volumes of more than 15 km3 (3.6 cu mi), the largest and oldest which is Level Mountain with an area of 1,800 km2 (690 sq mi) and a volume of more than 860 km3 (210 cu mi). Apart from the large volcanoes, several smaller volcanoes exist throughout the Northern Cordilleran Volcanic Province, including cinder cones which are widespread throughout the volcanic zone. Most of these small cones have been sites of only one volcanic eruption; this is in contrast to the larger volcanoes throughout the volcanic zone, which have had more than one volcanic eruption throughout their history.The Northern Cordilleran Volcanic Province is part of an area of intensive earthquake and volcanic activity around the Pacific Ocean called the Pacific Ring of Fire. However, the Northern Cordilleran Volcanic Province is commonly interpreted to be part of a gap in the Pacific Ring of Fire between the Cascade Volcanic Arc further south and the Aleutian Arc further north. But the Northern Cordilleran Volcanic Province is recognized to include over 100 independent volcanoes that have been active in the past 1.8 million years. At least three of them have erupted in the past 360 years, making it the most active volcanic area in Canada. Nevertheless, the dispersed population within the volcanic zone has witnessed few eruptions due to remoteness and the infrequent volcanic activity.