DOI: 10.5281/zenodo.3951864
title: Refraction Microtremor Vs(z) Profile Archive

description: The PDF is a representation of a public website available at https://sites.google.com/view/vs-profile-archive

The time-averaged seismic shear-wave velocity from the surface to 30 m (100 ft) depth, defined in the Building Code as Vs30, is in the United States one of the principal determinants of earthquake site-hazard classification. Over the past 20 years the Nevada Seismological Lab and the Applied Geophysics class at the University of Nevada, Reno; and Optim Earth have made shallow (<1 km deep) shear-wave velocity measurements at hundreds of sites in Nevada, California, and New Zealand using refraction microtremor technology. Many of these measurements were made at stations in regional earthquake-monitoring networks, and sponsored by the US Geological Survey. The Google Drive link leads to a directory structure grouping the measurements by region, and the files are often named with the monitoring network station name. Each file is a self-explanatory, plain-text list of the data and results from the measurement. Where multiple files are given for a particular site, measurements were made at slightly different refraction microtremor array locations, at different times, and by different interpreters; thus expressing both the aleatory variation of velocity in the ground and the epistemic variability of the measurement technique (+/- 15% according to Louie, 2001). Each measurement file includes refraction microtremor array location data, a summary Vs30 value, and a modeled shear-wave-velocity-versus-depth profile. Efforts are underway to add the picked refraction microtremor p-f image and the picked fundamental-mode Rayleigh-wave dispersion-curve data to each file. Many of these measurements have been published in peer-reviewed journal papers and project reports (available in the Preprint Archive from Louie.pub). As well, these archives give additional details on refraction microtremor measurements found in the US Geological Survey's Vs30 archive at https://earthquake.usgs.gov/data/vs30/us/ . All data in this archive are in the public domain, distributed under a Creative Commons CC BY license.
description: An additional 10,722 Vs30 measurements in Las Vegas and Clark County, Nevada are available from the Clark County GIS system at http://gisgate.co.clark.nv.us/ow/ (under the "hamburger" options menu select the "Seismic" map type). A Pancha et al. (2017) paper describes these measurements. To apply the refraction microtremor technology to your engineering project, contact Terēan at terean.com. For more information on refraction microtremor applications, take a look at the draft refraction microtremor chapter of the COSMOS Guidelines document on surface-wave array measurement from https://link.springer.com/journal/10950/volumes-and-issues/26-4 .

Acknowledgements

Research, fieldwork, and data access were supported by: Optim Earth, Inc., Reno, NV (www.optimsoftware.com), Bill Honjas, Satish Pullammanappallil, Brendan Kissane. The Nevada Applied Research Initiative at UNR, Dick Bjur. The Nevada Seismological Laboratory, especially James N. Brune, Glenn Biasi, John G. Anderson, and Graham Kent. The CEMAT Project and the John Louie Research Fund of the UNR Foundation. The U.S. Department of Energy under instruments numbered DE-FG07-02ID14311 and DE-FG36-02ID14311, managed through the DOE Golden Field Office, and Lisa Shevenell and Mark Coolbaugh of the Great Basin Center for Geothermal Energy at UNR. The U.S. Geological Survey (USGS), Department of the Interior, under USGS award numbers 03HQGR0068, 05HQGR0078, 07HQGR0029, 08HQGR0015, 08HQGR0046, G09AP00050, G09AP00051, G10AP00002, G16AP00109, and G19AP00082 to Louie; and G11AP20022, G12AP20026, G14AP00020, and G15AP00055 to Optim (links to project reports, or papers); and many thanks also to Bill Stephenson. The University of California Lawrence Livermore National Laboratory under the auspices of the U.S. Dept. of Energy under Contract No. W-7405-Eng-48. We are particularly indebted to Jane Long, Shawn Larsen, Dave McCallen, Arthur Rodgers, Jeff Wagoner, and Hrvoje Tkalcic for their very effective collaboration. The Seismic Monitoring task of the Yucca Mountain Project, Harry Reid Center at UNLV, under the auspices of the U.S. Dept. of Energy. The instruments used in parts of the field program were provided by the PASSCAL facility of the Incorporated Research Institutions for Seismology (IRIS) through the PASSCAL Instrument Center at New Mexico Tech. Data collected during those experiments will be available through the IRIS Data Management Center. The facilities of the IRIS Consortium are supported by the National Science Foundation under Cooperative Agreement EAR-0004370 and by the Department of Energy National Nuclear Security Administration. We wish to thank Willie Zamora, Steve Azevedo, and Marcos Alvarez for all their help over the years. GNS Science, Lower Hutt, New Zealand, especially Stuart Henrys, Vaughn Stagpoole, Bill Stephenson, Jian Zhang, Peter Barker, and Graeme McVerry. GIS databases kindly provided by David Heron and Rafael Benites of GNS Science. Victoria University of Wellington, New Zealand, especially John Taber, Euan Smith, Martha Savage, Tim Stern, and John Townend. The U.S. Department of State and Fulbright New Zealand, Mele Wendt and Peggy Tramposch. University of Texas El Paso, Texan Instrument Center, Steve Harder, Randy Keller, and Galen Kaip. The Engineering Geophysical Lab at UNLV, especially Jim O'Donnell, and Barbara Luke, who maintained a geotechnical database for Las Vegas. The Geosciences Dept. at UNLV, Cathy Snelson and Wanda Taylor. Black Eagle Consulting, Inc., Reno, NV, Larry Johnson and Ted Beeston. UNAVCO, Inc., and the National Science Foundation, Michael Hasting. Disclaimers The ReMi technology is owned by the University of Nevada, and licensed exclusively to Optim Earth, Inc. Optim pays royalties to the University based on their commercial revenues from ReMi. As inventor of the technology, under University policy John Louie personally receives a share of those royalties. This report and the materials linked here were prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions or authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Any measurements and observations made within approximately 50 km of Yucca Mountain, Nevada, and specifically any locations or magnitudes of seismic events, are preliminary information only. Please contact the archive of the Yucca Mountain Project Technical Library to obtain quality-assured technical data relating to seismic activity, ground conditions, or other natural phenomena near Yucca Mountain. The information included in these documents is intended to improve earthquake preparedness; however, it does not guarantee the safety of an individual structure or facility. The State of Nevada does not assume liability for any injury, death, or property damage that occurs in connection with an earthquake.