Kinematics of Footwall Exhumation at Oceanic Detachment faults: Solid?Block Rotation and Apparent Unbending
نویسندگان
چکیده
Seafloor spreading at slow rates can be accommodated on large-offset oceanic detachment faults (ODFs), that exhume lower crustal and mantle rocks in footwall domes termed core complexes (OCCs). Footwall experience large rotation during exhumation, yet important aspects of the kinematics—particularly relative roles solid-block flexure—are not clearly understood. Using a high-resolution numerical model, we explore exhumation kinematics beneath an emergent ODF/OCC. A key feature models is motion dominated by rotation, nonplanar, concave-down fault interface. consequence curvature measured along ODF representative neutral stress configuration, rather than “bent” one. Instead, it subsequent process “apparent unbending” significant flexural stresses are developed model footwall. The brittle strain associated with apparent unbending produced dominantly extension, OCC, consistent earthquake clustering observed Trans-Atlantic Geotraverse Mid-Atlantic Ridge.
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ژورنال
عنوان ژورنال: Geochemistry Geophysics Geosystems
سال: 2021
ISSN: ['1525-2027']
DOI: https://doi.org/10.1029/2021gc009681