Quantifying Natural Fault Geometry: Statistics of Splay Fault Angles

Publication Status is "Submitted" Or "In Press: 
LDEO Publication: 
Publication Type: 
Year of Publication: 
2009
Editor: 
Journal Title: 
Bulletin of the Seismological Society of America
Journal Date: 
Feb 1
Place Published: 
Tertiary Title: 
Volume: 
99
Issue: 
1
Pages: 
389-395
Section / Start page: 
Publisher: 
ISBN Number: 
0037-1106
ISSN Number: 
Edition: 
Short Title: 
Accession Number: 
ISI:000266181100030
LDEO Publication Number: 
Call Number: 
Abstract: 

We propose a new approach to quantifying fault system geometry, using an objective fit of the fault geometry to a test function, specifically here a fault branch. Fitting a Y-shaped object using a cost function to dextral faults in California, we find a number of significant results arising from use of a a systematic, objective, quantitative approach. (1) The largest angle of the branch structure is generally very close to 180 degrees, implying that the branch is a splay fault off the primary through-going fault. (2) The distribution of the smallest angle, the splay angle, has a peak near +/- 17 degrees, symmetric about the primary fault. (3) These features appear independent of scale. These results are not yet explained by any theory, and they pose new questions and constraints for the physics of fault system formation and behavior.

Notes: 

447HBTimes Cited:0Cited References Count:17

DOI: 
Doi 10.1785/0120080942