Monday, June 30, 2014

Report on 1887 Sonora earthquake now online

Saturday night's M5.2 Duncan earthquake triggered renewed interest in the M7.2 Sonora earthquake that shook much of the same region but with roughly 1,000 times as much energy. 

In response, Dubois and Smith’s “The 1887 Earthquake in San Bernardino Valley, Sonora: Historic Accounts and Intensity Patterns in Arizona” is now online at the AZGS document repository for reading or download -

Sunday, June 29, 2014

AZGS news release on Duncan M5.2 earthquake

AZGS issued the following news release this afternoon:

A magnitude (M) 5.2 earthquake struck rural southeastern Arizona near Duncan, Arizona, on the New Mexico border just before 10 p.m. Saturday night. The U.S. Geological Survey’s online tool “Did you feel it” received more than 2,300 “felt” responses, some from as far west as Phoenix and as far east as Alamogordo, New Mexico. Residents near Duncan and surrounding communities reported moderate shaking. There are no reports of injuries or significant damages.
Preliminary analysis of earthquake data from the Arizona Integrated Seismic Network operated by the Arizona Geological Survey (AZGS) indicates about a dozen earthquake events, including a probable foreshock of approximately 3.0M at 5:57 p.m. on June 28. The main 5.2M event was followed by at least 9 aftershocks, four of magnitude 3.0 or greater (attached map). The first aftershock, a 3.5M event occurred at 10:22 p.m. on June 28, a 3.4M aftershock occurred at 1:29 a.m. on June 29th, and a third 3.6M at 7:33 a.m. on June 29th. The latest measurable event, 3.3M occurred at 8:40 a.m. on June 29th. Many smaller aftershocks undoubtedly occurred but have not been detectable by our seismometers. The earthquakes make a NW-SE trend extending for about 5 miles. All events were shallow, occurring less than 6-miles deep. Historical seismicity in this area, including the recent events, as well as the mapped Quaternary faults, can be viewed at the online interactive Natural Hazards in Arizona Viewer on the AZGS website [].

The largest historical earthquake in the southeastern Arizona – southwestern New Mexico – northern Mexico region was the M~ 7.5M event in May 1887 on the Pitaycachi fault of northern Sonora, Mexico, about 25 miles south of Douglas, Arizona. This is considered the largest earthquake likely to occur in this region. A  M5.5 earthquake occurred on August 17, 1938, near Buckhorn New Mexico, and M4.5 events occurred soon after in the Duncan and Clifton areas. In May 2010 and October 2012, small earthquake swarms, with earthquake events ranging from M2.0 to M4.1, occurred about 45 miles north-northeast of Duncan, in the Morenci-Clifton area of northern Greenlee County. 

According to US Geological Survey probability models, the likelihood of a substantial M5.0+ earthquake within 31 miles of Clifton-Morenci area over the next 25 years is ~20%.

It is likely that small magnitude aftershocks will continue in the Duncan area for days or weeks. Most will probably go unfelt.  A larger magnitude event could still occur.  In the event of severe ground shaking, residents are advised to “Drop, Cover and Hold on”.

Online Resources.  The Arizona Geological Survey hosts a number of online resources relevant to earthquakes and earthquake hazards in Arizona:
·         Natural Hazards in Arizona  Active Faults | Earthquake Epicenters themes
·         Earthquakes in Arizona 1852-2011 – Time lapse video showing locations and magnitudes of earthquake events in Arizona. Length: 90 seconds.
·         Arizona is Earthquake Country – Forty-four page primer on earthquakes, earthquake hazards and mitigation in Arizona.
·         Great Arizona ShakeOut – Online earthquake preparedness information and drill.
·         AzEIN – Earthquake Preparedness page from Arizona Emergency Information Network

Arizona Geological Survey social media information outlets:
Arizona Geology Blog                    
Arizona Geological Survey Facebook
Arizona Geological Survey Twitter

Historical magnitude 5-6 earthquakes in Arizona

A lot of Arizona residents were surprised by last night's M5.2 earthquake, saying that Arizona doesn't have such things.

But we record a couple of hundred events around the state every year, although quakes this big are relatively rare.

AZGS geologists Mike Conway and Jeri Young provided this graphic showing all historical earthquakes in the M = 5-6 range [right], using the AZGS online Hazards Viewer -

Seismic waveforms from Duncan M5.2 earthquake

The waveforms from last night's M5.2 Duncan earthquake have been compiled by AZGS seismologist, Dr. Jeri Young.    AZGS runs the 7-station Arizona Broadband Seismic Network which provides statewide monitoring and links to stations run by USGS and Northern Arizona University.

How to report what you felt from the M5.2 earthquake

Nearly 2200 people have logged onto the USGS site to describe how much shaking they experienced from last night's magnitude 5.2 earthquake in eastern Arizona.      If you felt it, we encourage you to share your experience at

This information provides valuable scientific data that we use to better understand how the shock waves travel across the region and how local geologic conditions may dampen or enhance ground shaking.  This is critical in helping better design buildings and critical infrastructure.   [Right, waveform of last nights earthquake from seismometer station X16A, part of the AZGS-managed Arizona Broadband Seismic Network.  Credit, Dr. Jeri Young, AZGS]

Strong earthquake - magnitude 5.2 - hits eastern Arizona

A magnitude 5.2 earthquake struck a remote area of southeastern Arizona near the New Mexico border just before 10 p.m. Saturday night.  More than 2,000 reports of it being felt have been filed with the USGS, coming from all over southeast Arizona and southwest New Mexico [below].  Ground shaking is reported as strong near the epicenter, and moderate to light or very light further away.  [Right, orange circles mark epicenters of main shock and aftershocks.  The light blue circle is the newest event. Credit, USGS]

Two aftershocks of magnitude 3.5 and 3.4 occurred within a couple of hours of the big shock and a 3.6 event occurred while I was writing this post Sunday morning. More aftershocks can be expected.

The epicenter is about 31 miles northwest of Lordsburg, 52 miles west-southwest of Silver City, and 89 miles northeast of Douglas.

AZGS geologists are examining our records for historical earthquakes in the region and any known active faults.  We'll share that information as it becomes available.

Saturday, June 28, 2014

AZGS moves to new office in Phoenix

The AZGS Phoenix branch completed a move to new office space, co-located with the Arizona Dept. of Water Resources.  We are occupying part of the 4th floor, above ADWR.   The address is 3550 N. Central Ave, Phoenix. Phone numbers and email for staff will remain the same.

AZGS moved out of the "temporary" space occupied since the former ADMMR had to move out of the old mineral museum into unused lab space across the parking lot.  ADMMR was then merged with AZGS and we advised our state landlord that the space would not work long term because of the lack of public access, size and layout, and need for renovation.

Our Phoenix team will be unpacking and arranging files and the library for a while but are open for business.  Visitors are already coming in.   Check in with the ADWR visitors desk.

Friday, June 27, 2014

Another quake in northern Arizona

There was a second earthquake on Wednesday in northern Arizona.  A magnitude 2.4 event occurred at 2:40 pm local time about 20-30 miles west of Fredonia, where a magnitude 2.2 quake had hit at 2:05 a.m. that morning.   [Right, orange star marks the epicenter.  Red lines are active faults. Credit Univ. of Utah Seismograph Stations and USGS]

The bottom map shows location of the earlier event.

Wednesday, June 25, 2014

M=2.2 earthquake near Fredonia

A magnitude 2.2 earthquake hit about 4 miles south of Fredonia, Arizona at 2:05 a.m. this morning.

[Right, the orange star marks the epicenter.  The red lines are active fault traces. Credit, USGS]

Friday, June 20, 2014

New State Cartographer named for Arizona

Curtis Pulford, the Wisconsin Geographic Information Officer, has been appointed Arizona State Cartographer, which is housed in the State Land Dept.He will be filling the position recently vacated by Gene Trobia and will begin on Monday July 7th. [Photo source, Linkedin]

According to Vanessa Hickman, Executive Director of the State Land Dept. "Curtis has lived and worked in Wisconsin for many years as that state’s Geographic Information Officer (GIO), where he was responsible for the statewide coordination of all GIS partnerships and resources.  One of his key recent accomplishments was building and implementing a State Spatial Data Repository.  This experience will serve him and the Land Department well as we continue our efforts as a member of the Governor’s Natural Resource Review Council (NRRC), the NRRC GIS subcommittee and the NRRC Clearinghouse subcommittee.  Within this GIO role, Curtis has routinely been called upon to lead coordination meetings with public stakeholders, legislators and business executives in order to design and optimize GIS solutions at the statewide level.     

Curtis also worked for nearly a decade for the Wisconsin Department of Transportation as GIS manager.  Before that he lived and worked in Arizona for Pima County as a GIS professional, so he is familiar with many of the unique challenges and opportunities we manage."

Tuesday, June 17, 2014

Responses posted to Rosemont Copper objections

Coronado National Forest officials have posted responses to the objections raised about the proposed Rosemont Copper mine in the Santa Rita Mountains.   Responses are targeted to each person or organization that made objections.

Regional Forester Calvin Joyner said they received 114 objections by the deadline, of which 101 were deemed eligible.   In his response letters to the objectors, Joyner stated that he found the "project is in compliance with these [environmental] laws, regulations, policies, and Forest Plan.  However, by copy of this letter, I am instructing the Forest Supervisor to complete consultation with the USFWS [US Fish & Wildlife Service] and address the clarifications and corrections I identified above prior to signing the Final ROD [Record of Decision]."

The latter condition appears to refer to further consultation with USFWS over the siting of an ocelot in the region, something which had been anticipated in the EIS.   Otherwise, my quick reading of the documents found what appear to be only relatively minor corrections, clarifications, or revisions.

Sunday, June 15, 2014

Wildfires & monsoon mean floods and debris flows - hazard assessed at Sedona's Slide fire

Wildfires burn away hillside vegetation and lead to flooding and debris flows (commonly called mudslides). With the official start of the monsoon season today, which is predicted to be wetter than normal, areas recently burned such as the area between Sedona and Flagstaff in the Slide fire, are at higher risk.  

Local news reports on the results of the Burn Area Emergency Response (BAER) team evaluation indicate an 8-times greater risk of flooding as a result of the Slide fire.   AZGS geologist Dr. Ann Youberg is our debris flow specialist and participates in BAER team assessments.

Similar hazards and risks exist across the Western U.S.   A new online hazard assessment system was unveiled by the USGS last week that includes the Slide fire.   It shows substantial areas with 60-80% probability of debris flows based on 10-year storms.  A few small areas reach the 80-100% probability range.

[From the USGS explanation: The interactive map above displays estimates of the probability of debris flow (in %), potential volume of debris flow (in m3), and combined relative debris flow hazard. These predictions are made at the scale of the drainage basin, and at the scale of the individual stream segment. Estimates of probability, volume, and combined hazard are based upon a design storm with 10-year recurrence interval (i.e., a 1 in 10 chance of a storm of that magnitude occurring in any given year). Predictions may be viewed interactively by clicking on the button at the top right corner of the map displayed above. Visit the Scientific Background page for more information on how the predictions are calculated. For more information about what to do in case you live in an area where debris flows are possible, please visit If you live in a recently burned area, and there is a rainstorm…]

AGU blogger Alexandra Branscombe took a look at predicting post-fire mudslides in the Western U.S.  at

Google Earth view of Arizona earth fissures

AZGS geologist Joe Cook, who manages our Earth Fissures mapping program, has created a Google Earth view of all the Earth Fissures identified in Arizona thus far. The Google Earth app complements the online interactive Earth Fissure Viewer which is widely used by home buyers, home builders, real estate professionals, and local planners.  

The Google Earth view is available at

Earth fissures typically form due to basin subsidence in areas of rapid groundwater withdrawal.  Fissures have formed in Maricopa, Pinal, Pima, and Santa Cruz counties in Arizona, but also occur in California, Texas, Mexico, and other areas with similar conditions.

Sunday, June 08, 2014

Earth fissures now available on Google Earth

You can now view Arizona's earth fissures on Google Earth  thanks to AZGS project manager Joe Cook.     You can access the viewer through  our Maps and Database Services page at

[Right, distribution of mapped earth fissures in Cochise, Maricopa and Pinal Counties as shown in the Google Earth environment]

The Earth Fissure Viewer at remains as the official source of Earth Fissure maps and information for those involved in the real estate - development businesses.

Thursday, June 05, 2014

7-ounce gold nugget stolen from UA Mineral Museum

The University of Arizona Police Department reported yesterday that, "On Saturday May 30, 2014 at approximately 2:30 p.m., a gold nugget from the Hubert de Monmonier Collection was stolen from the Flandrau Planetarium at the University of Arizona. The gold nugget measures 3.11 in. x 1.26 in. by .9 in. (7.9 cm x 3.2 cm x 2.3 cm) and weighs .48 pounds (7 ounces). The nugget is valued at $30,000 and is well-known to the mineral community and museum enthusiasts."    [Photo credit, UA Police Dept.]

Wednesday, June 04, 2014

UA short course on ore deposits mapping

We received this announcement today and  are sharing it in full:

University of Arizona Lowell Program in Economic Geology
Short Course on Ore Deposits Mapping
August 28 - September 6, 2014

Yerington porphyry and skarn mapping exercises, and field trip of ore-forming systems in the Great Basin

Dear Colleagues:
We are opening registration for the tenth offering of our Short Course on Ore Deposits Mapping, which
will take place Thursday, August 28 through Saturday, September 6, 2014. A tentative outline is
given below.

Course Details:
As has been tradition in the U of A’s advanced ore deposits curriculum over the last 15 years, Mark
Barton and Eric Seedorff will again be leading the extended field trip and mapping course through the
Great Basin. It will be an opportunity to see ore deposits of various types and ages, set in the context of
the structural and magmatic evolution of the region. The trip is designed for graduate students taking an
advanced ore deposits class, but we will make available approximately 25 seats for members of industry.
The trip will include a focused multi-day introduction to the “Anaconda-style” of detailed mapping in
the Yerington district, Nevada. The district contains porphyry copper and skarn mineralization, but the
mapping method is adaptable to any type of deposit. As part of this, we highlight how mapping can be
used to understand zoning, the time-space evolution of mineralizing systems, and the relationships to the
fundamental phase equilibria of hydrothermal alteration. In addition to numerous other geologic stops,
the trip also anticipates to include overviews and/or tours of the following districts and deposits:
  • Tonopah, Nevada [low-sulfidation epithermal Ag-Au],
  • Goldfield, Nevada [high-sulfidation epithermal Au],
  • Birch Creek, California [F-Be-W-(Zn) greisen/skarn],
  • Humboldt, Nevada [IOCG occurrences],
  • Eureka district, Nevada [partially superimposed systems, with a Carlin-type Au mine at Archimedes, a porphyry Mo-Cu to replacement Zn-Pb-Ag deposit at Ruby Hill, and the top of a F-W-Zn-Be-(Mo-Sn) system at McCullough Butte]
  • Robinson district, Nevada [porphyry Cu-(Mo-Au) and related skarn and distal Au-Ag deposits].

The trip is 10 days round trip from Las Vegas, covering about 25
participants should plan to arrive in Las Vegas no later than Wednesday evening August 27, as the trip
leaves early on Thursday morning August 28. Industry participants should also plan to depart from Las
Vegas no earlier than late Thursday evening September 06, 2014.
00 miles in 4WD vehicles. Industry

The early registration cost of the trip for non-university participants is US$3,200, which includes ground
transportation, all lunches in the field, double-occupancy accommodations in motels each night during
the trip, and course materials. Breakfasts and most dinners are the responsibility of participants. Industry
participants also will need to provide their own transportation to and from Las Vegas as well as their
accommodations the night preceding and following the trip. Please respond via e-mail to for reservations. Register soon! This sort course sells out quickly.

Please find enclosed to this letter all registration materials (registration and foreign visitor statement
forms in English and in Spanish as well as the documentation required for foreign nationals (non US
citizens) so that you can forward this information to your co-workers and friends.

Visit our webpage: to learn more about our program and short courses
We also take the opportunity to inform you that our Short Course on Porphyry Deposits will take place
again December 9-18, 2014. This 9-day short course has a focus on exploration geology that includes
3½ days of lectures and 2 days of labs in Tucson, and 3½ days of field trips to representative ore
systems in Arizona. As in years past, we will send the registration materials for this course in late July.

Exemption period for geologist licensure in Louisiana

We received this news from the Louisiana Board of Professional Geoscientists that describes the possibility for registered geologists in Arizona and other states to be eligible for licensure in Louisiana without having to take the exam there.  [Right, geologic map of Louisiana. Credit, EPA]
Louisiana Representative Hunter Greene’s House Bill 167 on professionallicensure for geologists has become law. Act 228, effective May 28, 2014, amends and reenacts the Louisiana Revised Statute 37:711.14(B) and 711.15(A)(4)(b) relative to the Louisiana Professional Geoscience Practice Act as follows:

§711.14(B) Examinations – The Board may adopt or recognize, in whole or in part, an examination prepared, administered, or graded by another organization, on a regional or national basis, that the board determines appropriate to measure the qualifications of an applicant for a license under this Chapter; however the board retains the authority to determine a passing grade for a license in this state on an adopted or recognized examination prepared, administered, or graded by another organization, on a regional or national basis.
 §711.15(A)(4)(b) License eligibility – An applicant who applies for licensure under this Chapter prior to January 1, 2015, shall be exempt from taking the examination described in Subparagraph (a) of this Paragraph if the applicant satisfies all the other requirements of this Subsection.

For more information, contact: 
Georgeann McNicholas
Executive Secretary
Louisiana Board of Professional Geoscientists
9643 Brookline Ave., Ste. 101
Baton Rouge, LA  70806
ofc. 225-389-6116
fax  225-448-2964
cell 225-505-3766