title: Fault slip rates in the modern new madrid seismic zone
abstract: Structural and geomorphic analysis of late Holocene sediments in the Lake County region of the New Madrid seismic zone indicates that they are deformed by fault-related folding above the blind Reelfoot thrust fault. The widths of narrow kink bands exposed in trenches were used to model the Reelfoot scarp as a forelimb on a fault-bend fold; this, coupled with the age of folded sediment, yields a slip rate on the blind thrust of 6.1 +/- 0.7 mm/year for the past 2300 +/- 100 years. An alternative method used structural relief across the scarp and the estimated dip of the underlying blind thrust to calculate a slip rate of 4.8 +/- 0.2 mm/year. Geometric relations suggest that the right lateral slip rate on the New Madrid seismic zone is 1.8 to 2.0 mm/year.
authors.affiliation: Department of Geological Sciences, University of Colorado, Boulder, CO 80309-0399, USA. Department of Geology, University of Arkansas, Fayetteville, AR 72701, USA. William Lettis and Associates, 1777 Botelho Drive, Suite 262, Walnut Creek, CA 945.
authors.initials: K
authors.lastname: Mueller
authors.initials: J
authors.lastname: Champion
authors.initials: M
authors.lastname: Guccione
authors.initials: K
authors.lastname: Kelson