1 / 17

F 3 - Faults, Fractures and Flexures in Three-Dimensions:

F 3 - Faults, Fractures and Flexures in Three-Dimensions: Field Observations at the Dead Sea Basin Ze'ev Reches School of Geology and Geophysics, University of Oklahoma. Multi-scale deformation in basin margins: A. Bending of the crust into the basin B. Zig-zag faulting in basin margins

malo
Télécharger la présentation

F 3 - Faults, Fractures and Flexures in Three-Dimensions:

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. F3- Faults, Fractures and Flexures in Three-Dimensions: Field Observations at the Dead Sea Basin Ze'ev Reches School of Geology and Geophysics, University of Oklahoma Multi-scale deformation in basin margins: A. Bending of the crust into the basin B. Zig-zag faulting in basin margins C. Local bending of layers above the faults D. Fractures associated with local bending

  2. Study area Taurus Mts. 200 km N Dead Sea basin Mediterranean Sea Dead Sea Transform Sinai 20 km Arabian plate African plate Arabian plate Sinai subplate

  3. W E W E ? ? ? c b a 5 km A B A. Bending of the crust and basin sedimentation B. Zig-zag faulting in basin margins C. Local bending above the faults D. Fractures associated with bending B A

  4. A. Bending into a pull-apart basin B. Zig-zag faulting in basin margins C. Local bending above the faults D. Fractures associated with local bending 80,185 Dead Sea 1 km (Agnon, 1983) Cumulative fault length: 176 km 40,178 N Emunah-1

  5. a 31005’ 15 m 1 km 31003’ Zig-zag fault in the field (top) Structural map of a typical part of the Dead Sea margins (left). Close-up view of a sand-cake extension experiment (right).

  6. Nahal Parsa section Hazera Fm. Lisan Fm. 10 m W E b 3 2 2 1 ? 2 I 2 1 4 II 3 100m III A. Bending into a pull-apart basin B. Zig-zag faulting due to 3D strain C. Local bending above the faults D. Fractures associated with bending

  7. Bending above faults m=0.0 Surface distribution of tensile fractures 250m Inclined zone of tensile fractures A B A B Flexed layers from Boldt, unpublished B Fault D D Faults C C

  8. A. Bending into a pull-apart basin B. Zig-zag faulting due to 3D strain C. Local bending above the faults D. Fractures associated with bending • Implications: • Faults and fracture orientations • Fracture density distribution

  9. Hever 8 Mishmar (lower) Hever (lower) hever 10 Ye’elim (lower) Bokek (lower) A. Bending into a pull-apart basin B. Zig-zag faulting due to 3D strain C. Local bending above the zig-zag faults D. Fractures associated with bending Hever 7 N 1m Hever 9 fracture orientations

  10. Trends of faults from geologic maps fractures in field Fractures in subsurface Similarity of trends of faults and fractures; Dead Sea margins

  11. E W ~ 50 m 3.3 m Fault zone

  12. a b c N Dead Sea Transform 20cm 200km 2km 200m 20km Areal stress-state Plate-scale stress field Local stress-state

  13. Map ofshminabove zig-zag normal faults (green=tensile). (stresses calculate for 0.5 km depth; faults dip 75o eastward; faults from 2 km to 15 km below surface; dislocations) 5 km Fault strand Trend & relative magnitude of tensile shmin

  14. Large, steeply dipping fractures Gently inclined bedding surfaces Opened zones of unknown origin on borehole surface N E S W N N E S W N CAST images of Emunah-1 borehole 564m of images in depth interval: 1400- 2700m, 550 identified fractures (classes A-D), 73 in classes A-B (used in the analysis).

  15. North Idealized fault pattern, western margins of Dead Sea basin Anderson, 1951 Reches, 1983

  16. Inclined zone of tensile fractures B Flexed layers Fault W E Hazera formation Lisan formation 10 m

More Related