Nevada Bureau of Mines and Geology,
University of Nevada, Reno
Open-File Report 11-11
Preliminary Geologic Map of the Northern Lake Range, San Emidio Geothermal Area, Washoe County, Nevada
by Gregory T. Rhodes, James E. Faulds, and Alan R. Ramelli
2011
http://www.nbmg.unr.edu/dox/of1111.pdf (plate)
http://www.nbmg.unr.edu/dox/of1111_text.pdf (text)OF11-11, 1:24,000-scale color plate, 36 x 38 inches; 5-page text, b/w, $18.00
http://www.nbmg.unr.edu/sales/pbsdtls.php?sku=OF11-11
Craig dePolo to lead discussion on earthquake hazards
MEETING ANNOUNCEMENT
Thursday, May 17th, 2012
SPEAKER: Craig dePolo, PhD, Nevada Bureau of Mines and GeologyLOCATION:
Reno Ramada – Skyline Room
1000 E. Sixth Street, Reno, Nevada
Link to MapSOCIAL HOUR: 5:30 PM
DINNER: 6:00PM
PRESENTATION: 6:30PM
RSVP BY TUESDAY MAY 15 (5:00 PM) TO JESSE RUZICKA, 775-331-2375 OR JESSE.RUZICKA@AMEC.COM
Cost: Members: $25.00; non-members: $29.00; Students: $15.00
(Note that the first 3 students that RSVP will receive a free dinner!)
www.aegweb.org
“Fault Setbacks as Mitigation for Rupture Hazard in Nevada” ABSTRACT
Craig dePolo would like to engage in a discussion of fault set-backs as a mitigation strategy for surface faulting hazard. The Nevada Earthquake Safety Council is currently reviewing the recommended set-back strategies for surface rupture hazard from faults in Nevada. After a presentation on the current ideas in play, we'll collectively talk about what approaches make the most sense for Nevada and why. As a society, we need to reduce the losses from earthquake events because it can be exceedingly difficult and take a long time to recover from an event. But societal solutions commonly conflict with individual liberties and desires. So what should we do, what can we do? Can we build close to a fault with proper exploration techniques? If so, what are those techniques and how effectively can they be implemented? Can a geologist call the displacement on a fault during the next earthquake with confidence so buildings can be constructed across faults safely? There are advocates of this. What is the liability for geologists if they underestimate displacement? Can an uncertainty statement handle this? Please bring your observations and suggestions.BIOGRAPHY
Craig dePolo is a research geologist with the Nevada Bureau of Mines and Geology. He is a masters and PhD graduate of the Mackay School of Mines. He focuses on earthquake hazards, Quaternary faults, and historical earthquakes in Nevada. He is the Northern Nevada Geoscience Representative to the Nevada Earthquake Safety Council.
Microearthquakes Associated With Long Period, Long Duration Seismic Events During Stimulation of a Shale Gas Reservoir
presented by Indrajit Das (from Zoback's Stress and Geomechanics Group at Stanford)
ABSTRACT
Long period, long duration (LPLD) seismic events are relatively low amplitude signals that appear to be generated by slowly slipping faults during hydraulic stimulation of a gas shale reservoir. They are remarkably similar in appearance to tectonic tremor sequences observed in subduction zones and transform fault boundaries. In most cases, micro-earthquakes occur during the LPLD events, most likely generated on small fault segments associated with the slowly slipping faults responsible for the LPLD events. Interestingly, the hydraulic fracturing stages associated with the most LPLD events in the data set investigated lie exactly where there is a significant low amplitude anomaly in the 3D seismic data which we believe is due to a large density of pre-existing fractures and faults in this part of the reservoir. This region also shows the highest perturbation in pore pressure during hydraulic fracturing. From the spectrum of LPLD events we estimate that the moment carried by the larger LPLD events is ~10-20 times that of a Mw ~ -1 microearthquake. The relatively large size of these LPLD events suggests that slow slip on faults is an important process affecting the stimulation. Stimulating slip on these preexisting faults in response to elevated fluid pressures can help optimize field operations and improve recovery for shale gas reservoirs.
UNR campus map:
http://www.unr.edu/around-campus
Seismo Lab:
http://www.seismo.unr.edu/
Nevada Today (May 3, 2012):
Rapid Sierra Nevada uplift tracked by scientists at the University of Nevada, Reno—by Mike Wolterbeek
http://www.unr.edu/nevada-today/news/2012/sierra-nevada-uplift
Reno Gazette-Journal (May 5, 2012):
Mountains getting taller, stressing faults
http://www.rgj.com/apps/pbcs.dll/article?AID=/201205060600/NEWS/305060069
Geology (published online April 27, 2012; to be published in July 2012 issue):
Contemporary uplift of the Sierra Nevada, western United States, from GPS and InSAR measurements—by William C. Hammond, Geoffrey Blewitt, Zhenhong Li, Hans-Peter Plag, and Corné Kreemer
http://geology.gsapubs.org/content/early/2012/04/27/G32968.1.abstract
More about Bill Hammond’s research:
http://www.nbmg.unr.edu/Staff/Hammond.html
Nevada Geodetic Laboratory:
Due to significant budget cuts, the NBMG Analytical Laboratory will close on June 30, 2012. However, NBMG can provide a list of commercial laboratories that routinely do analytical work for industry, and NBMG staff can assist Nevada residents with quality assurance and interpretation of the results. Quality assurance includes standard reference materials, (for which multiple laboratories have reported consistent results), duplicates (two splits of the same sample), and blanks (samples of random rocks, such as basalt or granite that are unlikely to contain ore). NBMG will continue to sell standard reference materials for gold, silver, and some trace elements. Information on obtaining these reference materials is provided below.
The last day that samples will be accepted for testing will be May 8, 2012.
If you have any questions, please contact Mario Desilets:
http://www.nbmg.unr.edu/Staff/Desilets.html
phone: (775) 682-8774
e-mail: desilets@unr.edu
NBMG Analytical Laboratory web page:
http://www.nbmg.unr.edu/Departments/AnalyticalLab/index.html
NBMG is announcing the sale of new standard reference materials for three Carlin-type gold ores:
NBM-8a is a low-grade oxide ore standard having a recommended gold concentration of 0.049 ounces/ton.
NBM-8b is a high-grade oxide ore standard having a recommended gold concentration of 0.290 ounces/ton.
NBM-8c is a high-grade refractory ore standard having a recommended gold concentration on 0.397 ounces/ton with very high arsenic concentration.
All three standards have a broad suite of trace-element data reported. These new SRMs are available in 300-gram bottles for $100.00 or 30-gram bags for $15.00.
NBMG standard reference materials:
http://www.nbmg.unr.edu/Departments/AnalyticalLab/SRM.html
GPS technology developed at Nevada used for NASA quake monitoring test
Nevada Geodetic Lab operates largest GPS network processing system in world
Read article by Mike Wolterbeek (Nevada Today, April 25, 2012):
http://www.unr.edu/nevada-today/news/2012/gps-technology-helps-nasa
“GPS technology developed and implemented at the University of Nevada, Reno will be the centerpiece of a major test this year by NASA to pinpoint the location and magnitude of strong earthquakes along the West Coast of the United States. The project was announced by NASA today.”
NASA tests GPS monitoring system for big U.S. quakes
NASA news release:
http://www.nasa.gov/topics/earth/features/earth20120424.html
Article in Sacramento Bee:
http://www.sacbee.com/2012/04/24/4438698/nasa-tests-gps-monitoring-system.html
New geodesy class:
Geoff Blewitt, Research Professor at NBMG, will teach a new geodesy class this Fall 2012 offered by the Department of Physics at the University of Nevada. The class is PHYS 484/694 Special Problems in Physics: "Physics and Engineering of GPS." It will cover the physics and engineering principles of the Global Positioning System for millimeter-precision positioning and sub-nanosecond timing.
http://www.nbmg.unr.edu/Staff/Blewitt.html
Dinner Meeting: Thursday, May 3, 2012
Ramada Reno Hotel; 6:30 PM
1000 East 6th Street, Reno, NV 89512
Speaker (1): Gregory Dering
Graduate Student, Dept. of Geological Sciences and Engineering, UNR
Title: Structural Controls of the Tuscarora Geothermal Field, Elko County, NV
Speaker (2): Bill Ehni
Geologist, Ehni Enterprises, Inc., Carson City, NV
Title: Submarine Deposition of Tufa in Pyramid Lake, Washoe County, NV
Cocktail Reception 6:30, Skyline Bar, 14th Floor
Redeem your dinner ticket for a drink at the Skyline Bar
Hosted by Barbour Well, Inc.
Dinner Served at 7:00 PM
NPS Members $20; Non-Members $23; Students $10
Menu:
Buffet style including chicken & beef entrees with side dishes and salad
**RSVP by Tue May 1 to Diane Phillips (775) 267-4663 or trailsend@pyramid.net
MI-2010--This report, the thirty-second of an annual series, describes mineral, oil and gas, and geothermal activities and accomplishments in Nevada in 2010: production statistics, exploration and development including drilling activity, discoveries of orebodies, new mines opened, and expansion of existing mines. Statistics of known gold, silver, and other metallic deposits, and directories of mines and mills are included. This report is only available on the Web:
http://www.nbmg.unr.edu/dox/mi/10.pdf
Open-File Report 11-7: Preliminary revised geologic maps of the Reno urban area, Nevada
by Alan R. Ramelli, Christopher D. Henry, and Jerome P. Walker,
with contributions by John W. Bell, Patricia H. Cashman, Craig M. dePolo, Larry J. Garside, P. Kyle House, James H. Trexler, and Michael C. Widmer
2011
This study developed a comprehensive, unified stratigraphy for the Quaternary, Cenozoic, and Mesozoic rocks of the Reno urban area that can be extended to adjacent areas. The study also completely remapped Quaternary and older faults in the area based on extensive new surface and subsurface data. Six new cross sections are the first to depict the overall structure of the Truckee Meadows basin. The maps are compiled in ArcGIS so that they can be continuously updated as additional data become available.
Open-File Report 11-7 was revised from these published geologic maps from NBMG:
Urban Map 4Gg, Geologic map of the Verdi quadrangle, John W. Bell and Larry J. Garside (1987);
Urban Map 4Ag, Geologic map of the Reno quadrangle, Harold F. Bonham and Edward C. Bingler (1973);
Urban Map 4Hg, Geologic map of the Vista quadrangle, John W. Bell and Harold F. Bonham (1987);
Urban Map 5Ag, Geologic map of the Washoe City quadrangle, R.W. Tabor and S. Ellen (1975);
Urban Map 4Bg, Geologic map of the Mt. Rose NE quadrangle, Harold F. Bonham Jr. and David K. Rogers (1983); and Urban Map 4Fg, Geologic map of the Steamboat quadrangle, Harold F. Bonham Jr. and John W. Bell (1993)
Supersedes Open-File Report 10-11.
Available free on the Web or for purchase--http://www.nbmg.unr.edu/sales/pbsdtls.php?sku=OF11-7
OF11-7, 3 color plates, scale 1:24,000-scale, each plate 80x42 inches, rolled only, $66.00 for the set of 3 plates
You may purchase these individual plates by calling 775-682-8766. They will be available on our shopping cart next week.
OF11-7-1 (plate 1 only, north half) $22.00
OF11-7-2 (plate 2 only, south half) $22.00
OF11-7-3 (plate 3 only, cross sections) $22.00
