20 Transform Plate Boundaries - North Coast Distance Education
... The Romanche fracture zone is a series of deep valleys separated by ridges. One narrow ridge rises above sea level to make cluster of small islands—St. Peter and St. Paul’s Rocks, one of the few oceanic island groups that did not form by volcanism. The floor of this zone is fractured and grooved and ...
... The Romanche fracture zone is a series of deep valleys separated by ridges. One narrow ridge rises above sea level to make cluster of small islands—St. Peter and St. Paul’s Rocks, one of the few oceanic island groups that did not form by volcanism. The floor of this zone is fractured and grooved and ...
Seismogeodynamics of Lineament Structures in the Mountainous
... sutures was supposed to play a certain role in the occurrence of the Gazli earthquakes because it is known that the largest earthquakes occur precisely at such fault nodes. A hypothetical seismic source on the Mangyshlak Peninsula identified from ancient faults and possibly also confined to the inte ...
... sutures was supposed to play a certain role in the occurrence of the Gazli earthquakes because it is known that the largest earthquakes occur precisely at such fault nodes. A hypothetical seismic source on the Mangyshlak Peninsula identified from ancient faults and possibly also confined to the inte ...
P-and S-wave velocities of the lowermost crustal rocks from the
... granulite) were collected around the lithological boundary and showed similar major element compositions (Table 1). The Vp and Vs results suggest that garnet granulite formation from two-pyroxene granulite causes a marked increase in Vp (+0.31 km/s) and Vs (+0.27 km/s). Figure 6 shows the Vp and Vs ...
... granulite) were collected around the lithological boundary and showed similar major element compositions (Table 1). The Vp and Vs results suggest that garnet granulite formation from two-pyroxene granulite causes a marked increase in Vp (+0.31 km/s) and Vs (+0.27 km/s). Figure 6 shows the Vp and Vs ...
Subduction erosion modes: Comparing finite
... margins; however the underlying causes are not well constrained. Finite-element numerical models of ocean–continent subduction are used to investigate the roles of crustal frictional strength, subduction angle, and convergence rate in subduction erosion processes. Subduction erosion occurs in models ...
... margins; however the underlying causes are not well constrained. Finite-element numerical models of ocean–continent subduction are used to investigate the roles of crustal frictional strength, subduction angle, and convergence rate in subduction erosion processes. Subduction erosion occurs in models ...
lithosphere 2006 - Helsingin yliopisto
... T. Stålfors, C. Ehlers and A. Johnson. The granite-migmatite zone of southern Finland – A history of structural control and intrusions I.T. Kukkonen and L.S. Lauri. Modelling the thermal evolution of a Precambrian orogen: high heat production migmatitic granites of southern Finland L.S. Lauri, M. Cu ...
... T. Stålfors, C. Ehlers and A. Johnson. The granite-migmatite zone of southern Finland – A history of structural control and intrusions I.T. Kukkonen and L.S. Lauri. Modelling the thermal evolution of a Precambrian orogen: high heat production migmatitic granites of southern Finland L.S. Lauri, M. Cu ...
Crystal Fractionation processes at Baru Volcano from the Deep to
... amphibole-bearing cumulates that provide an opportunity to probe the magma plumbing system of an active arc volcano. In this study, we use amphibole compositions from crystals hosted in the most recent products of Baru volcanism along with whole rock major and trace element analyses to evaluate Baru ...
... amphibole-bearing cumulates that provide an opportunity to probe the magma plumbing system of an active arc volcano. In this study, we use amphibole compositions from crystals hosted in the most recent products of Baru volcanism along with whole rock major and trace element analyses to evaluate Baru ...
Seamounts – characteristics, formation, mineral deposits and
... year, these represent >80% of the roughly 5,350 eruptions recorded in historic times (Schmincke, 2004). Depending on the nature of seismic layer 3 (gabbros) volcanism at the MOR varies between <5km3/year and >20km3/year and contrasts with volumes of 1.5 and 1.7km3/year computed for hotspot and islan ...
... year, these represent >80% of the roughly 5,350 eruptions recorded in historic times (Schmincke, 2004). Depending on the nature of seismic layer 3 (gabbros) volcanism at the MOR varies between <5km3/year and >20km3/year and contrasts with volumes of 1.5 and 1.7km3/year computed for hotspot and islan ...
PDF version - Western Washington University
... D. Brown and P.D. Ryan (eds.), Arc-Continent Collision, Frontiers in Earth Sciences, DOI 10.1007/978-3-540-88558-0_5, # Springer-Verlag Berlin Heidelberg 2011 ...
... D. Brown and P.D. Ryan (eds.), Arc-Continent Collision, Frontiers in Earth Sciences, DOI 10.1007/978-3-540-88558-0_5, # Springer-Verlag Berlin Heidelberg 2011 ...
Mantle Convection in the Earth and Planets - U
... convection is the primary mechanism for the transport of heat from the Earth’s deep interior to its surface, it is the underlying cause of plate tectonics, formation and drift of continents, volcanism, earthquakes, and mountain building processes. It also shapes the gravitational and magnetic fields ...
... convection is the primary mechanism for the transport of heat from the Earth’s deep interior to its surface, it is the underlying cause of plate tectonics, formation and drift of continents, volcanism, earthquakes, and mountain building processes. It also shapes the gravitational and magnetic fields ...
5. Structure of the Outer Izu-Bonin Forearc from Seismic
... geophysical surveys were made over the Izu-Bonin arc. These surveys include the 96-trace multichannel seismic-reflection (MCS) data collected using the Fred H. Moore of the University of Texas Institute for Geophysics. In this chapter, we present and interpret the MCS data as well as model marine gr ...
... geophysical surveys were made over the Izu-Bonin arc. These surveys include the 96-trace multichannel seismic-reflection (MCS) data collected using the Fred H. Moore of the University of Texas Institute for Geophysics. In this chapter, we present and interpret the MCS data as well as model marine gr ...
Dyke swarm emplacement in the Ethiopian Large Igneous Province
... and Head, 1994; Me'ge and Masson, 1996). Dyke swarms are thus key contributors to plume tectonics analysis. As far as the Ethiopian LIP is concerned, the term £ood basalt province should be avoided because it incorrectly re£ects the composition and emplacement of the lavas erupted in response to the ...
... and Head, 1994; Me'ge and Masson, 1996). Dyke swarms are thus key contributors to plume tectonics analysis. As far as the Ethiopian LIP is concerned, the term £ood basalt province should be avoided because it incorrectly re£ects the composition and emplacement of the lavas erupted in response to the ...
The lunar moho and the internal structure of the Moon
... on the origin of the solar system or even the Moon until comparatively recently, given the complexity in having to assimilate a vast amount of data from differing fields. In pre-Apollo times it was commonly believed that the Moon compared to Earth is geologically an inactive planet and exactly for th ...
... on the origin of the solar system or even the Moon until comparatively recently, given the complexity in having to assimilate a vast amount of data from differing fields. In pre-Apollo times it was commonly believed that the Moon compared to Earth is geologically an inactive planet and exactly for th ...
- ERA - University of Alberta
... in a mid-crustal channel will smooth the surface subsidence caused by the dense lithosphere; crustal flow in a lower-crust channel can cause the surface to invert to become a topographic high. Magmatism caused by lithosphere removal depends on the removal style and the initial thermal structure of ...
... in a mid-crustal channel will smooth the surface subsidence caused by the dense lithosphere; crustal flow in a lower-crust channel can cause the surface to invert to become a topographic high. Magmatism caused by lithosphere removal depends on the removal style and the initial thermal structure of ...
Downdip landward limit of Cascadia great earthquake rupture
... of fully seismic rupture is expected to be somewhat seaward of the limit for the modeled interseismic locked zone because some release of the locked zone strain buildup, especially the deep part, is in postseismic slip [e.g., Wang, 2007; Hu and Wang, 2012; Wang et al., 2012], so the limit from the g ...
... of fully seismic rupture is expected to be somewhat seaward of the limit for the modeled interseismic locked zone because some release of the locked zone strain buildup, especially the deep part, is in postseismic slip [e.g., Wang, 2007; Hu and Wang, 2012; Wang et al., 2012], so the limit from the g ...
IODP Proposal Cover Sheet
... This proposal is for the ultra-deep drilling site of a series of IODP proposals in the Izu-Bonin-Mariana (IBM) arc that aim at comprehensive understanding of arc evolution and continental crust formation. We propose to drill a deep hole that penetrates through a complete sequence of intra-oceanic ar ...
... This proposal is for the ultra-deep drilling site of a series of IODP proposals in the Izu-Bonin-Mariana (IBM) arc that aim at comprehensive understanding of arc evolution and continental crust formation. We propose to drill a deep hole that penetrates through a complete sequence of intra-oceanic ar ...
Important Notice
... pairs to estimate empirical Green’s Functions. This thesis is made up of there separate studies. The first is an isotropic application of the ambient-noise tomography method to image crustal structure beneath Hudson Bay. Results show crustal thinning beneath the Bay, allowing us to reject a hypothes ...
... pairs to estimate empirical Green’s Functions. This thesis is made up of there separate studies. The first is an isotropic application of the ambient-noise tomography method to image crustal structure beneath Hudson Bay. Results show crustal thinning beneath the Bay, allowing us to reject a hypothes ...
Mapping the Moho with seismic surface waves: A review, resolution
... Regional crustal models and Moho maps have also been constructed using combinations of both active-source and passive seismic data, as well as other geophysical and geological data (e.g., Grad et al., 2009; Kissling, 1993; Molinari and Morelli, 2011; Tesauro et al., 2008; Thybo, 2001). Seismic surfa ...
... Regional crustal models and Moho maps have also been constructed using combinations of both active-source and passive seismic data, as well as other geophysical and geological data (e.g., Grad et al., 2009; Kissling, 1993; Molinari and Morelli, 2011; Tesauro et al., 2008; Thybo, 2001). Seismic surfa ...
The ocean-continent boundary in the Gulf of Lion from analysis of
... appear typically oceanic in nature, (c) quite typical oceanic crust up to the Sardinian margin. Gravity modelling is consistent with the seismic results. The OCB (ocean-continent boundary) could be placed north of that postulated by previous authors, where the data indicate a remarkably narrow trans ...
... appear typically oceanic in nature, (c) quite typical oceanic crust up to the Sardinian margin. Gravity modelling is consistent with the seismic results. The OCB (ocean-continent boundary) could be placed north of that postulated by previous authors, where the data indicate a remarkably narrow trans ...
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.