Fault size distributions - are they really power-law?



A. Nicol, J. J. Walsh, J. Watterson & P .A. Gillespie

Abstract - Power-law fault size (throw) distributions spanning ca 7 orders of magnitude are analysed using sample lines from seismic, coal-mine plan and outcrop data sets. Outcrop data sets generally have lower power-law exponent values than seismic data sets, consistent with a general decrease in exponent value with decrease in fault size. If such a relationship does exist then it probably cannot be accounted for by sampling bias alone. We suggest that, either i) fault-size populations are not power-law over a large scale range, or ii) they are power-law, but at smaller scales show a greater range of exponent values due to spatial clustering.


Journal of Structural Geology 18, 191-197, 1996.