20 extension

40 6 0
  • Loading ...
1/40 trang

Thông tin tài liệu

Ngày đăng: 29/11/2016, 23:34

Normal Faults Extensional Tectonics Tectonic Settings for Extension • Divergent plate motions • Gravitational collapse – Over-thickened crust – Continental margins • Salt Domes Extensional Tectonics Divergent Boundary Normal Faults, rifts Continental Extension Divergent Boundaries Continental Plate Separation Parallel valleys; volcanoes and earthquakes East African Rift Valley a te l P an c i r f A Soma l i S ub plate Rifts Bounded by normal faults Back Arc extension Domino block rotation in the Basin and Range Listric (curved) Faults- roll over anticlines Small roll-overs Sedimentation during faulting Growth faulting Animation by R Allmendinger http://www.geo.cornell.edu/geology/faculty/RWA/movies/ km Curved faults – Block rotation Growth Strata Gulf of Mexico Passive Margin Gulf of Mexico Salt Extension Above Salt Diapir Transfer zone in a rift Successive generations of normal faults •Older faults rotate and become inactive •New faults cross-cut them •Result= large magnitude extension [...]... Extension of the lithosphere 1 Extension of the lithosphere 2 Lithospheric Extension •Thinning of the lithosphere •Normal faulting at the surface •High heat flow (rinsing of the isotherms) •Thermal subsidence - > sedimentary basins North Sea Extensional Basin Pure shear vs simple shear systems Gravitational Collapse of Mt... sedimentary basins North Sea Extensional Basin Pure shear vs simple shear systems Gravitational Collapse of Mt Belts Basin and Range Province New Mountains-Active Fault –Basin and Range Province Two modes of extension Sandbox- Block rotation Sand above plasticine Block Rotation Domino block rotation in the Basin and Range Listric (curved) Faults- roll over anticlines Small roll-overs Sedimentation during faulting... Growth faulting Animation by R Allmendinger http://www.geo.cornell.edu/geology/faculty/RWA/movies/ 0 3 km Curved faults – Block rotation Growth Strata Gulf of Mexico Passive Margin Gulf of Mexico Salt Extension Above Salt Diapir Transfer zone in a rift
- Xem thêm -

Xem thêm: 20 extension , 20 extension , 20 extension

Gợi ý tài liệu liên quan cho bạn

Nạp tiền Tải lên
Đăng ký
Đăng nhập