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Showing 1 to 10 of 10 for “"lower oceanic crust"”.
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The accretion of lower oceanic crust
… control on the composition of the oceans, ocean crust, and upper mantle. Two complementary approaches are used to investigate the thermal implications of endmember theoretical models that describe the accretion of the lower oceanic crust at fast spreading rates. The first approach uses the record …
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Fracture Analysis of the Lower Oceanic Crust, Atlantis Bank, Southwest Indian Ridge
<p>Atlantis Bank (AB) is an oceanic core complex (OCC), formed at the slow-spreading (spreading rate/yr) Southwest Indian Ridge (SWIR)-Atlantis II transform junction. AB is a domal massif composed of lower crustal and upper mantle rocks exhumed along a normal-sense detachment shear zone/fault. OCCs …
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Deciphering the signature of fluid/rock reactions in the lower oceanic crust: The Oman ophiolite analogue
… moderating elemental and heat transfers between oceanic lithosphere and the hydrosphere. The characterization and quantification of fluid/rock reactions and fluid fluxes in fast-spreading mid-ocean ridges has been a long-term ambition given these ridges are responsible for formation of two thirds …
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The primary structures and fabrics of the upper mantle and lower oceanic crust from ophiolite complexes
The structures and textures of areas from the lower sequences of the Oman Ophiolite, the Troodos Ophiolite, Cyprus, and the Shetland Ophiolite have been studies in order to gain an understanding of the structural and kinematic history of the upper mantle and lowermost oceanic crust at accretionary …
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Structural Re-orientation of Magmatic Fabrics and Layering in the Lower Oceanic Crust: Hole GT1, Wadi Tayin Massif, Samail Ophiolite
… Drilling Project to better constrain models of crustal accretion. The gabbro glacier model proposes that crystallized basalt flows down and away from the crystallization site to form the lower crust while the sheeted sill model proposes that basaltic melt crystallizes at multiple levels in the …
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The Impact of Fe-Ti Oxide Concentration on the Structural Ridgity of the Lower Oceanic Crust, Atlantis Bank, Southwest Indian Ridge
<p>Fe-Ti oxides are important components of oceanic core complexes (OCC) formed at slow-spreading mid-ocean ridges since Fe-Ti oxides are more susceptible to crystal-plastic deformation than silicate minerals. This study investigated the predicted relationship between the presence and concentration …
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The Effects of Amphibole- and Sulfide-Producing Melts on Crustal Strength in Gabbros of Lower Oceanic Crust in Oceanic Core Complexes, Mid-Atlantic and Southwest Indian Ridges
<p>This study investigates gabbro-cored oceanic core complexes in the slow-spreading Mid-Atlantic Ridge (MAR) and the ultraslow spreading Southwest Indian Ridge (SWIR). Dikelets are a texture found in thin section samples from these systems that form as a result of crystal-plastic deformation. Thin …
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The evolution of oceanic gabbros : in-situ and ancient examples
… geochemical investigation into the accretion of lower oceanic crust and processes of shallow melt-rock reaction at mid-ocean ridges. Major-, trace-elements, and isotopes from whole-rocks and minerals from the Lyngen Gabbro, a 480-My old dismembered ophiolite from the Scandinavian Caledonides, …
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Evolution of oceanic gabbros : in-situ and ancient examples
… geochemical investigation into the accretion of lower oceanic crust and processes of shallow melt-rock reaction at mid-ocean ridges. Major-, trace-elements, and isotopes from whole-rocks and minerals from the Lyngen Gabbro, a 480-My old dismembered ophiolite from the Scandinavian Caledonides, …
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Subduction zone wave guides : deciphering slab structure using intraslab seismicity at the Chile-Peru subduction zone
… at the contact zone between continental and oceanic crust (70 km depth). Guided waves bearing information on deep slab structure can therefore be recorded at specific regions in the forearc. These regions are determined based on slab geometry, and their locations coincide with the …