Discussion and reply: Kinematic evolution of a large-offset continental normal fault system, South Virgin Mountains, Nevada

Abstract

In the canonical cross-sectional reconstruction of relationships at Yerington (Proffett, 1977, Fig. 15), approximately two-thirds of ~65° of rotation of Tertiary strata occurs on a first generation of faults, the remaining third (20°–25°) occurring on later generations of crosscutting faults. Given the lack of evidence for multiple generations of faults in the South Virgin Mountains, we sought to critically evaluate this interpretation, which we cited as an example of multiple-domino-style normal faulting, and assess whether published data require the first set of faults to have deactivated at dips of 30°, or instead permit them to have remained active near their current dips of 10°– 20°. Our reinterpretation of one of Proffett’s cross sections (Brady et al., 2000, Fig. 15B) depicts the second generation of faults as having relatively little displacement, and as having slipped synchronously with the first generation.