Outline: Normal Fault Systems and Kinematics
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Planar Faults and Block Rotation
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Detachment Faulting
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Fault Linkage
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Kinematics of Normal Faulting
Development of Continental Rift into Ocean Basin
Upwelling of hot mantle
Thins, weakens, and
cracks the lithosphere
Development of Continental Rift into Ocean Basin
Rift Valley
Early graben formation
prior to continental
splitting. This stage
may be associated
with domal uplift
caused by uprise of hot
upper mantle material uplift may be
connected with
underlying mantle
hotspots.
Development of Continental Rift into Ocean Basin
Young ocean basin
Last about 50 my after the
onset of seafloor spreading,
while the thermal effects are
still dominant.
Characterized by rapid
regional subsidence of the
outer shelf and slope, but
some graben formation may
persist. Example: Red Sea.
Development of Continental Rift into Ocean Basin
Mature Ocean basin
Subdued regional
subsidence may continue.
Example: most of the
present Atlantic
continental margins.
East African Rift Segmentation
16 mm/a (GPS)
9 mm/a (GPS)
Basin and Range Normal Fault Blocks
Rio Grande
Rift
Segmentation
Death Valley
Fault Zone
Fault Stepover
Closeup of Stepover
Planar Normal Faults and Block Rotation
Planar Normal Faults and Block Rotation
Domino Block Example
Domino Block Example
Detachment Fault
Detachment Fault
Detachment Fault
Soft-Linked Systems
Kinematics of Normal Faulting
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Domino, Bookshelf-Style Normal Faulting
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Listric Normal Faulting with Reverse Drag
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Imbricate Listric Normal Faulting
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Inversion
Domino-Style Normal Faulting
Domino-Style Normal Faulting (bookshelf faulting)
Occurs above Detachment faults
Listric-Planar Normal Fault System
???
Listric-Planar Normal Fault System
L
Listric Normal Faulting with Reverse Drag
Listric Normal Faulting with Rollover
Occurs due to space problem with curved detachment
Imbricate Listric Normal Faulting
Synthetic faults also accommodate collapse of HW block
Imbricate Listric Normal Faulting
“Meatslices common in large displacement systems
Inversion
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Normal faulting
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Syn-tectonic deposition of B
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Post-tectonic deposition of C
Inversion
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Normal faulting
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Syn-tectonic deposition of B
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Post-tectonic deposition of C
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Thrust faulting
Deformation of B and folding
of C
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References
Slides 1, 20, 21
Twiss, R. J. and E. M. Moores, Structural Geology, W. H. Freeman & Co., New York, 532 p.,
1992.
Slides 3-6
http://earth.leeds.ac.uk/faults/normal/domino.htm
Slides 7-9
http://earth.leeds.ac.uk/faults/normal/detachment1.htm
Slide 10
http://earth.leeds.ac.uk/faults/soft/softnormal.htm
Slides 12-19
Davis. G. H. and S. J. Reynolds, Structural Geology of Rocks and Regions, 2nd ed., John
Wiley & Sons, New York, 776 p., 1996.