Seismic reflection profiling in the Proterozoic Arunta Block, central
... greenschist facies. The Ngalia Basin (Wells and Moss, 1983) lies within the Arunta Block (Fig. la). and its northern margin is also fault-controlled; it is not an important feature on the seismic reflection section because the ma~mum sedimentary thickness along the profile A-A’ does not exceed 1 km. ...
... greenschist facies. The Ngalia Basin (Wells and Moss, 1983) lies within the Arunta Block (Fig. la). and its northern margin is also fault-controlled; it is not an important feature on the seismic reflection section because the ma~mum sedimentary thickness along the profile A-A’ does not exceed 1 km. ...
Long-Term Volumetric Eruption Rates and Magma Budgets Scott M
... volcano; longer periods are generally required for volcanic centers erupting more compositionally-evolved magma due to lower eruption recurrence interval. Thus, a period of ~103 years may be a long time for a basaltic shield volcano (e.g., Kilauea, Hawaii) but captures only an insignificant fraction ...
... volcano; longer periods are generally required for volcanic centers erupting more compositionally-evolved magma due to lower eruption recurrence interval. Thus, a period of ~103 years may be a long time for a basaltic shield volcano (e.g., Kilauea, Hawaii) but captures only an insignificant fraction ...
Shallow-crustal magma chamber beneath the axial high of the
... Fuca Ridge extends from ;5 to ;80 km north from the summit caldera of Axial volcano, the most recent of the Cobb-Eickelberg chain of volcanoes (Fig. 1). The Coaxial segment occupies an en echelon position with respect to the north rift of Axial volcano. Magmatism and resulting crustal accretion of t ...
... Fuca Ridge extends from ;5 to ;80 km north from the summit caldera of Axial volcano, the most recent of the Cobb-Eickelberg chain of volcanoes (Fig. 1). The Coaxial segment occupies an en echelon position with respect to the north rift of Axial volcano. Magmatism and resulting crustal accretion of t ...
Seismic and aseismic deformation along the East African Rift
... activity (Ebinger 1989a,b; Ebinger et al. 1993; Hayward & Ebinger 1996; Delvaux & Khan (1998); Kurz et al. 2007). The complexity of the boundary therefore makes both the short-term and the longterm kinematics of the EARS difficult to understand. The recent geodetic data offer a good opportunity to m ...
... activity (Ebinger 1989a,b; Ebinger et al. 1993; Hayward & Ebinger 1996; Delvaux & Khan (1998); Kurz et al. 2007). The complexity of the boundary therefore makes both the short-term and the longterm kinematics of the EARS difficult to understand. The recent geodetic data offer a good opportunity to m ...
Seismic Monitoring - K-UTEC
... A rather quick and also more intense reaction on the flooding could be observed in area D, which is characterised by a more complex tectonic situation. The period of high energy release was limited to a few month, where seismic events with magnitudes larger than M L=1.0 were registered at very short ...
... A rather quick and also more intense reaction on the flooding could be observed in area D, which is characterised by a more complex tectonic situation. The period of high energy release was limited to a few month, where seismic events with magnitudes larger than M L=1.0 were registered at very short ...
V structural models associated with
... supplied from the hot upper mantle beneath the thin oceanic crust to the east, from the surrounding hotter upper mantle beneath the thickened continental crust, and from shear heating during active collision. The collision zone in eastern Taiwan is characterized by an active and steeply eastward dip ...
... supplied from the hot upper mantle beneath the thin oceanic crust to the east, from the surrounding hotter upper mantle beneath the thickened continental crust, and from shear heating during active collision. The collision zone in eastern Taiwan is characterized by an active and steeply eastward dip ...
Episodic Tremor and Slip
... subduction zone. (top panel) Cross-section through a subduction zone illustrating 3 types of fault behavior: locked (solid), episodic tremor and slip (ETS, dashed), and creep (dotted). Boxes A through D show locations of seismic and GPS instruments above each of these 3 zones of the plate interface ...
... subduction zone. (top panel) Cross-section through a subduction zone illustrating 3 types of fault behavior: locked (solid), episodic tremor and slip (ETS, dashed), and creep (dotted). Boxes A through D show locations of seismic and GPS instruments above each of these 3 zones of the plate interface ...
Thermal state of the lithosphere in the Danube Basin and its relation
... thermo-physical parameters. The data from Slovakia were published in plenty of partial studies and were summarized mainly in Král et al. (1985) and in Franko et al. (1995). These publications also contain interpretations of geothermic data in the form of terrestrial heat flow density distribution, t ...
... thermo-physical parameters. The data from Slovakia were published in plenty of partial studies and were summarized mainly in Král et al. (1985) and in Franko et al. (1995). These publications also contain interpretations of geothermic data in the form of terrestrial heat flow density distribution, t ...
Karson, J.A., and Lawrence, R.M., 1997. Tectonic setting of
... Seafloor spreading is accomplished by a combination of mechanical extension and magmatic construction. Along fast-spreading ridges, where nearly continuous axial magma chambers have been identified (Detrick et al., 1987; Toomey et al., 1990), the extrusion of lavas, injection of dikes, and accretion ...
... Seafloor spreading is accomplished by a combination of mechanical extension and magmatic construction. Along fast-spreading ridges, where nearly continuous axial magma chambers have been identified (Detrick et al., 1987; Toomey et al., 1990), the extrusion of lavas, injection of dikes, and accretion ...
The Petrogenetic Evolution of Lavas from Easter
... Intraplate volcanoes are widespread on Earth and make up large parts of the oceanic crust in many regions such as the East Pacific (Abers et al., 1988). Oceanic islands and seamounts have received much attention because their chemistry is not directly affected by contributions from continental mater ...
... Intraplate volcanoes are widespread on Earth and make up large parts of the oceanic crust in many regions such as the East Pacific (Abers et al., 1988). Oceanic islands and seamounts have received much attention because their chemistry is not directly affected by contributions from continental mater ...
Accreted oceanic terranes in Ecuador: Southern edge of the
... magmatism immediately followed the formation of the Piñón oceanic plateau, since 1 or 2 Ma are necessary before the downgoing slab reaches the magma generation depth. On the other hand, since the overlying deposits do not bear any evidence of arc activity, subduction-related magmatism would have cea ...
... magmatism immediately followed the formation of the Piñón oceanic plateau, since 1 or 2 Ma are necessary before the downgoing slab reaches the magma generation depth. On the other hand, since the overlying deposits do not bear any evidence of arc activity, subduction-related magmatism would have cea ...
Shallow crustal magma chamber of Coaxial Segment
... Finally, the Coaxial and Axial magma chambers appear to be unconnected on the seismic images. We are therefore led to conclude that the Coaxial magma chamber is being recharged from a mantle source below. The mantle sources of the hotspot-related Axial volcano and Coaxial segment of the Juan de Fuca ...
... Finally, the Coaxial and Axial magma chambers appear to be unconnected on the seismic images. We are therefore led to conclude that the Coaxial magma chamber is being recharged from a mantle source below. The mantle sources of the hotspot-related Axial volcano and Coaxial segment of the Juan de Fuca ...
Australian Journal of Earth Sciences - ePIC
... (green) predicts extension for the entire rift system, whereas Davey et al.’s (2006) model (magenta) predicts compression southeast of the DGGA, and our model (red) predicts right lateral strike-slip along the eastern branch of the rift system. Platemotion arrows with arrowheads are symbolic for ill ...
... (green) predicts extension for the entire rift system, whereas Davey et al.’s (2006) model (magenta) predicts compression southeast of the DGGA, and our model (red) predicts right lateral strike-slip along the eastern branch of the rift system. Platemotion arrows with arrowheads are symbolic for ill ...
7. Early Evolution of the South Atlantic Ocean: Role of the Rifting
... which resulted in the formation of the continental margin. The sediments may be deposited in depressions created in an early stage of development, as is the case for the Bay of Biscay where there was a tensional episode during the Permian-Liassic at the site of the future break-up of continents befo ...
... which resulted in the formation of the continental margin. The sediments may be deposited in depressions created in an early stage of development, as is the case for the Bay of Biscay where there was a tensional episode during the Permian-Liassic at the site of the future break-up of continents befo ...
Spatial, temporal and geochemical evolution of
... and Sr–Nd isotopic compositions, indicating common mantle melt sources and magmatic evolutionary trends. The isotopic signatures and trace element characteristics of these granitoids indicate that both lithospheric and asthenospheric mantle melts appear to have contributed to source region of the RM ...
... and Sr–Nd isotopic compositions, indicating common mantle melt sources and magmatic evolutionary trends. The isotopic signatures and trace element characteristics of these granitoids indicate that both lithospheric and asthenospheric mantle melts appear to have contributed to source region of the RM ...
THE EARTH`S GRAVITY OUTLINE The Earth`s gravitational field
... Some basic rules for gravity interpretation • Localised, short wavelength, anomalies can originate only from shallow density inhomogeneities. • Gravity alone cannot distinguish between a strong density contrast at depth and a more diffuse contrast shallow. Nevertheless large–scale gravity anomalies, ...
... Some basic rules for gravity interpretation • Localised, short wavelength, anomalies can originate only from shallow density inhomogeneities. • Gravity alone cannot distinguish between a strong density contrast at depth and a more diffuse contrast shallow. Nevertheless large–scale gravity anomalies, ...
u series disequilibria: insights into mantle melting and
... rocks are both expected and usually observed to have (234U/238U) = 1, then 238U can essentially be treated as the parent of 230Th. It is important to remember that for all these U series nuclide pairs both the parent and daughter nuclides are unstable and will undergo radioactive decay at different ...
... rocks are both expected and usually observed to have (234U/238U) = 1, then 238U can essentially be treated as the parent of 230Th. It is important to remember that for all these U series nuclide pairs both the parent and daughter nuclides are unstable and will undergo radioactive decay at different ...
pdf file - University of Victoria
... Lower crust flow has previously been concluded for several areas of tectonically thickened orogenic crust. The most studied currently active case is the Tibet high plateau and its flanks (e.g., Clark and Royden, 2000; Beaumont et al., 2001; 2004; 2006; Godin et al., 2006; Klemperer, 2006; Harris, 20 ...
... Lower crust flow has previously been concluded for several areas of tectonically thickened orogenic crust. The most studied currently active case is the Tibet high plateau and its flanks (e.g., Clark and Royden, 2000; Beaumont et al., 2001; 2004; 2006; Godin et al., 2006; Klemperer, 2006; Harris, 20 ...
Crystal preferred orientation of an amphibole experimentally
... mphibolites are considered one of the dominant rocks in the middle crust1, lower crust2 and deep crust of continental arcs3, where hydrous fluids are fluxed from the subducting slab and the water contents of underplating magmas are high2. As the primary anisotropic phase of amphibolite, amphibole is a ...
... mphibolites are considered one of the dominant rocks in the middle crust1, lower crust2 and deep crust of continental arcs3, where hydrous fluids are fluxed from the subducting slab and the water contents of underplating magmas are high2. As the primary anisotropic phase of amphibolite, amphibole is a ...
Thermal state of the lithosphere in the Danube Basin and its relation
... thermo-physical parameters. The data from Slovakia were published in plenty of partial studies and were summarized mainly in Král et al. (1985) and in Franko et al. (1995). These publications also contain interpretations of geothermic data in the form of terrestrial heat flow density distribution, t ...
... thermo-physical parameters. The data from Slovakia were published in plenty of partial studies and were summarized mainly in Král et al. (1985) and in Franko et al. (1995). These publications also contain interpretations of geothermic data in the form of terrestrial heat flow density distribution, t ...
Mantle plume
A mantle plume is a mechanism proposed in 1971 to explain volcanic regions of the earth that were not thought to be explicable by the then-new theory of plate tectonics. Some such volcanic regions lie far from tectonic plate boundaries, for example, Hawaii. Others represent unusually large-volume volcanism, whether on plate boundaries, e.g. Iceland, or basalt floods such as the Deccan or Siberian traps.A mantle plume is posited to exist where hot rock nucleates at the core-mantle boundary and rises through the Earth's mantle becoming a diapir in the Earth's crust. The currently active volcanic centers are known as ""hot spots"". In particular, the concept that mantle plumes are fixed relative to one another, and anchored at the core-mantle boundary, was thought to provide a natural explanation for the time-progressive chains of older volcanoes seen extending out from some such hot spots, such as the Hawaiian–Emperor seamount chain.The hypothesis of mantle plumes from depth is not universally accepted as explaining all such volcanism. It has required progressive hypothesis-elaboration leading to variant propositions such as mini-plumes and pulsing plumes. Another hypothesis for unusual volcanic regions is the ""Plate model"". This proposes shallower, passive leakage of magma from the mantle onto the Earth's surface where extension of the lithosphere permits it, attributing most volcanism to plate tectonic processes, with volcanoes far from plate boundaries resulting from intraplate extension.