Characterizing the Quaternary expression of active faulting along the Olinghouse, Carson, and Wabuska lineaments of the Walker Lane

Abstract

The northern Walker Lane (southwestern USA) accommodates ~5-7 mm/yr of right-lateral Pacific-North America relative plate motion. The northwest trend of major right-lateral faults in the Walker Lane is interrupted by the presence of northeast-striking left-lateral faults within the Carson and Excelsior domains. Previous studies in the Carson domain have suggested that left-lateral slip on the northeast-striking Olinghouse, Carson, and Wabuska lineaments accommodates Walker Lane transtensional dextral shear through the clockwise rotation of intervening crustal blocks. Our observations confirm and document the presence of late Pleistocene-Holocene faulting along each of these lineaments. Fault scarps along the Carson and Wabuska lineaments are discontinuous and sparse, and show evidence for left-lateral faulting, locally including linear fault traces, alternating scarp face directions, and lateral offsets of small gullies and ridges. The trends of scarps that define these lineaments link at their western ends with north-trending active normal faults. In this manner, it appears that the 5-7 mm/yr of right slip taking place across the northern Walker Lane is being accommodated by the combined processes of basin opening in the west and block rotation to the east. This mode of slip transfer differs from the Excelsior domain, where active left-slip faults and clockwise rotation of crustal blocks are confined to, and the result of, a distinct right step between right-lateral faults of the southern Walker Lane and central Walker Lane, respectively. The observation of these apparently diverse modes of development of left-slip faults and vertical axis rotations provides an example of the complexity that may be expected in the structural development of continental shear zones that have been characterized by transtension.

Late Quaternary slip rates for faults of the central Walker Lane (Nevada, USA): Spatiotemporal strain release in a strike-slip fault system

“…Alluvial fan formations are divided into three general units ( Fig. 2; Qfo-Middle to Late Pleistocene; Qfi-Late Pleistocene; Qfy-Holocene), primarily based on variations in surficial characteristics (e.g., degree of incision, breadth and shape of interfluves, and desert pavement development) following prior methods and general age delineations commonly applied to the region (Bull, 2008;Bell et al, 2004;Wesnousky, 2005a;Frankel et al, 2007a;Koehler and Wesnousky, 2011;Wesnousky and Caffee, 2011;Li et al, 2017). Descriptions of the mapped formations are provided in Supplemental Item A 1 .…”

“…Geodesy shows the contemporary strain field of the Walker Lane to be generally right-lateral shear dominated, with the principle strain axis oriented to the northwest, while a secondary component of north-south extension is evident in the central and southern portions of the Walker Lane (e.g., Oldow et al, 2001;Kreemer et al, 2009;Bormann et al, 2016). Active transtensional deformation occurs in the central Walker Lane across a system of active northwest-trending right-lateral strike-slip faults (e.g., Stewart, 1988;Wesnousky, 2005a), north-south-oriented normal faults (Unruh et al, 2003;Wesnousky et al, 2012), and a conjugate set of northeast striking left-lateral faults (Rogers, 1975;Wesnousky, 2005a;Li et al, 2017) (Fig. 1).…”

Accommodation of Plate Motion in an Incipient Strike‐Slip System: The Central Walker Lane

“…The northerly Carson domain (e.g. Cashman and Fontaine, 2000;Wesnousky, 2005;Li et al, 2017) is composed of the northeast-striking, sinistral Olinghouse fault (Briggs and Wesnousky, 2005) and the Carson and Wabuska lineaments (Li et al, 2017). This domain has accommodated >50° of clockwise vertical axis rotation since the Miocene (Cashman and Fontaine, 2000;Carlson, 2017).…”

“…The Central Walker Lane is here further subdivided into four domains based on orientations and kinematics of faults (Figure 1). The northerly Carson domain (e.g., P. H. Cashman & Fontaine, 2000; Li et al., 2017; Wesnousky, 2005) is composed of the northeast‐striking, sinistral Olinghouse fault (Briggs & Wesnousky, 2005), and the Carson and Wabuska lineaments (Li et al., 2017). This domain has accommodated >50° of clockwise vertical axis rotation since the Miocene (Carlson, 2017; P. H. Cashman & Fontaine, 2000).…”

Evidence of Aseismic and Fluid‐Driven Processes in a Small Complex Seismic Swarm Near Virginia City, Nevada

“…The Virginia City Sequence takes place within the footwall of the Virginia Range, east of the Reno basin ( Figure 1)-an area with short, distributed normal intermountain faults (Sawyer, 1999). The Virginia Range is bounded to the north and south by two left-lateral structures -the Olinghouse Fault and the Carson Lineament (Figure 1; Li et al, 2017). According to paleomagnetic studies by Cashman and Fontaine (2000), the Virginia Range is undergoing clockwise rotation at this latitude.…”