Late Quaternary faults in Las Vegas are in need of a modern state-of-the-art analysis of their earthquake potential. This news clip, prepared by Channel 3 in Las Vegas, reviews some of the Las Vegas Valley faults with a local reporter and how we can wisely develop around faults with ground rupture potential. A resident is featured on the clip that was unaware of the fault and earthquake hazard potential in Las Vegas. Unfortunately, this may be the norm and not the exception. It underscores the need for all Nevadans to be aware of their earthquake risks and do what they can to reduce them (please see http://www.nbmg.unr.edu/dox/sp27.pdf for mitigation information). Practicing the safest response to the next Nevada earthquakes can help prevent injuries from those events. Thus, we encourage everyone to sign up for the annual Nevada earthquake drill, the Great Nevada ShakeOut in October, and to practice Drop, Cover, and Hold during that exercise (see http://shakeout.org/nevada/).
…message from Craig dePolo
Link to the video:
Open-File Report 13-12
Evidence for High Contemporary Slip Rates along the Eglington Fault, Clark County, Nevada
by Craig M. dePolo, Wanda J. Taylor, and James E. Faulds
8 pages, color, $2.40:
or free online:
The Eglington fault in northern Las Vegas Valley is an unusual fault in that it is expressed as a faulted warp at the surface and accommodated a large vertical surface offset (10-14 m) in latest Pleistocene sediments relative to its short length of 11 km. Coupled with a competing hydro-compaction hypothesis for faults within Las Vegas Valley, the earthquake hazard of the Eglington fault has been poorly understood and likely underrepresented. Radiocarbon dates from faulted sediments in the area indicate that the vertical displacement across the fault has occurred in the last ~22 kyr. A preferred vertical fault slip rate of 0.6 m/kyr, and range of 0.25 to 0.9 m/kyr, are estimated using available data. How single event displacements are manifested along the Eglington fault and what the size of those displacements might be is not known, generating uncertainty in estimating the potential earthquake recurrence interval for the fault.