Imperial College London
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Dr Alex Whittaker

Faculty of Engineering, Department of Earth Science & Engineering

Reader in Landscape Dynamics
 
 
 
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Contact

 

+44 (0)20 7594 7491a.whittaker Website

 
 
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Location

 

3.51Royal School of MinesSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Hughes:2018:10.1016/j.epsl.2018.10.003,
author = {Hughes, A and Rood, DH and Whittaker, AC and Bell, RE and Rockwell, TK and Levy, Y and Wilcken, KM and Corbett, LB and Bierman, PR and DeVecchio, DE and Marshall, ST and Gurrola, LD and Nicholson, C},
doi = {10.1016/j.epsl.2018.10.003},
journal = {Earth and Planetary Science Letters},
pages = {198--210},
title = {Geomorphic evidence for the geometry and slip rate of a young, low-angle thrust fault: Implications for hazard assessment and fault interaction in complex tectonic environments},
url = {http://dx.doi.org/10.1016/j.epsl.2018.10.003},
volume = {504},
year = {2018}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - We present surface evidence and displacement rates for a young, active, low-angle (∼20°) reverse thrust fault in close proximity to major population centers in southern California (USA), the Southern San Cayetano fault (SSCF). Active faulting along the northern flank of the Santa Clara River Valley displaces young landforms, such as late Quaternary river terraces and alluvial fans. Geomorphic strain markers are examined using field mapping, high-resolution lidar topographic data, 10Be surface exposure dating, and subsurface well data to provide evidence for a young, active SSCF along the northern flank of the Santa Clara River Valley. Displacement rates for the SSCF are calculated over 103–104 yr timescales with maximum slip rates for the central SSCF of 1.9[Formula presented] mm yr−1 between ∼19–7 ka and minimum slip rates of 1.3[Formula presented] mm yr−1 since ∼7 ka. Uplift rates for the central SSCF have not varied significantly over the last ∼58 ka, with a maximum value of 1.7[Formula presented] mm yr−1 for the interval ∼58–19 ka, and a minimum value of 1.2±0.3 mm yr−1 since ∼7 ka. The SSCF is interpreted as a young, active structure with onset of activity at some time after ∼58 ka. The geometry for the SSCF presented here, with a ∼20° north dip in the subsurface, is the first interpretation of the SSCF based on geological field data. Our new interpretation is significantly different from the previously proposed model-derived geometry, which dips more steeply at 45–60° and intersects the surface in the middle of the Santa Clara River Valley. We suggest that the SSCF may rupture in tandem with the main San Cayetano fault. Additionally, the SSCF could potentially act as a rupture pathway between the Ventura and San Cayetano faults in large-magnitude, multi-fault earthquakes in southern California. However, given structural complexities, including significant changes
AU  - Hughes,A
AU  - Rood,DH
AU  - Whittaker,AC
AU  - Bell,RE
AU  - Rockwell,TK
AU  - Levy,Y
AU  - Wilcken,KM
AU  - Corbett,LB
AU  - Bierman,PR
AU  - DeVecchio,DE
AU  - Marshall,ST
AU  - Gurrola,LD
AU  - Nicholson,C
DO  - 10.1016/j.epsl.2018.10.003
EP  - 210
PY  - 2018///
SN  - 0012-821X
SP  - 198
TI  - Geomorphic evidence for the geometry and slip rate of a young, low-angle thrust fault: Implications for hazard assessment and fault interaction in complex tectonic environments
T2  - Earth and Planetary Science Letters
UR  - http://dx.doi.org/10.1016/j.epsl.2018.10.003
UR  - http://hdl.handle.net/10044/1/64539
VL  - 504
ER  -
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