Studying the Duncan M5.2 aftershocks: What can we learn?

The Arizona Geological Survey deployed 5 temporary seismic stations [Right.  Photo credit, Jeri Young, AZGS] in the Duncan area of eastern Arizona to better monitor the aftershocks following the June 28th, M 5.2 earthquake.

Monitoring earthquakes in the months following a moderate to larger sized event is an opportunity to gain knowledge about the how the Earth’s crust behaves in the area of the main quake. Measureable aftershocks can number in the several hundred.  Additional seismometers in the general area surrounding the main earthquake are needed to correctly estimate the number, size and location of the aftershocks.

Determining aftershock location and timing can provide information on fault rupture geometry (or shape), fault mechanics (type of movement) and provide insight into regional stresses. All of this information can be used to estimate the seismic hazard, and therefore help communities prepare themselves for future events.

Guest post by Jeri Young, AZGS

Duncan quake aftershock rocks Clifton

We are getting reports that another aftershock, M3.6,at 10:33 a.m. this morning shook buildings in Clifton, about 30 miles to the north-northwest.

[Right, orange star marks latest aftershock to the June 28, M5.2 Duncan earthquake.  Credit, USGS]

Duncan area hit by four larger aftershocks

The Duncan area experienced four more aftershocks in an 18 hour period  [right. credit USGS], with local residents reporting feeling them.   There was a M3.6 event at about 3 p.m. Thursday and a M3.2 at 11:15 p.m.   A M2.8 occurred at 1:38 a.m. this morning, followed by a M3.5 quake at 5:41 a.m. The Arizona Geological Survey is developing an interactive online map viewer to show all the aftershocks we are recording.    We installed 5 portable seismometers around the main shock epicenter area earlier this week which should be accurately recording not only these larger events but many other shocks that are too small to be felt.   

The Duncan M5.2 main shock hit on Saturday, June 28.

Temporary seismic stations capturing more aftershocks to Duncan earthquake

AZGS staff installed three more temporary seismometers yesterday, in the area around the M5.3 Duncan earthquake in eastern Arizona.  This brings the number of temporary stations to five.   AZGS geologists Jeri Young and Mike Conway observed half a dozen micro-quakes roll across the area just during lunch while they were installing the stations.     Mike posted details and photos at our Facebook page.  [Right, Jeri Young setting up temporary station]

At 1:15 a.m. this morning the area experienced a M3.6 aftershock which should have been captured by the new stations.     [Left, orange star marks aftershock epicenter.  Credit, USGS]

Freeport may sell off Chile mine to focus on US investments

Phoenix-based Freeport McMoRan Copper & Gold is  reportedly considering selling its huge Candelaria copper mine in Chile to help pay down corporate debt and refocus its efforts in the US, according to a story in the Wall Street Journal.   They say that Freeport may be negotiating with Aaron Regent, CEO of Canadian mining investment firm Magris Resources.      Interestingly, the WSJ had previously reported that Magris had looked at acquiring Augusta Resources, parent of  Rosemont Copper, during its takeover battle with HudBay Minerals.  [Right, Candelaria mine. Credit, Freeport McMoRan Copper & Gold]

Freeport CEO Richard Adkerson was noted to have said previously the company wants to put emphasis on exploration in the US because of more consistent environmental and labor regulations.  That fits with our perception that Freeport is increasing exploration in Arizona.

Candelaria, which is 80% Freeport and 20% Sumitomo owned, mined 370 million pounds of copper and 87,000 ounces of gold last year.    Freeport describes Candelaria as "an iron oxide, copper and gold deposit" with development of "an open-pit copper mine and a 6,000 metric ton-per-day (mtd) underground copper mine, which is mined by sublevel stoping."

Aftershocks continue from Duncan M5.3 earthquake

Two aftershocks with magnitudes over 3.0 hit the Duncan area on Saturday, a week after the 5.3 main shock occurred.

A magnitude 3.2 event hit at 12:30 pm, followed by a magnitude 3.5 shock at 9:24 pm.   [Right, the top orange circle is the M3.2 aftershock, the leftmost orange circle is the M3.5 event.   Credit, USGS]    The USGS only reports events greater than magnitude 3.0.   AZGS is identifying many more aftershocks in the 1.0 -3.0 range.

AZGS is working with the PASSCAL (Program for Array Seismic Studies of the Continental Lithosphere Instrument Center) instrument facility in Socorro, NM, to deploy a temporary network of 6 seismometers in the epicentral area.   In addition to better detection and location of continuing aftershocks, the information will help correct the locations of the 100+ aftershocks already recorded.

BLM raises fees on mining claims and sites by 10%; Arizona claim numbers declining

The US Bureau of Land Management increased its fees on unpatented mining claims, mill sites and tunnel sites on federal public lands by about 10%, effective June 30, 2014, according to a story on Mineweb.com.

The number of Federal Mining Claims reported in Arizona today is 43,490, according to AZGS Economic Geologist Nyal Niemuth.  There has been a big drop in lode claims from 40,018 to 34,632 since Jan 17, the last time we queried the total.  The total number then was 49,991. Nyal thinks the drop is a result of uranium claims on the Colorado Plateau being dropped.  The 10 year trend is shown in the figure above.

The BLM website describes recording fees for new claims:

Location Fee has increased from $34 to $37. 

All Mining Claims located on or after September 1, 2014, will cost a total of $212:
•    $20 Processing Fee (filing fee)
•    $37 Location Fee
•    $155 Maintenance Fee (Placer claims over 20 acres must pay an additional $155
• For each 20 acres or portion thereof.)


All monies are due at the time of filing. A claim will not be accepted unless the payment of the maintenance and locations fees is submitted. 

The initial $155 maintenance fee is due for the assessment year in which the claim is located (not recorded). This fee is not prorated. 

Mining claim holders must now pay the new location and maintenance fees for any mining claim or site located on or after September 1, 2014, according to the Federal Register. Mining claimants must also pay the new maintenance fee for existing mining claims and sites to maintain those claims and site, beginning with the 2015 assessment year.  However, all maintenance fees must be paid in advance for the upcoming 2015 assessment year.

All Federal mining claims for locatable minerals are filed with BLM, part of Dept of Interior. The Forest Service (Dept. of Agriculture) generally does not own the minerals under the surface it manages.

By agreement BLM allows Forest Service to manage the surface impacts of mining within Forest Service areas. Thus, the Forest Service approves plans of operations, etc. for mining claims.

USGS Historical Topo Map Explorer online

The USGS has an Historical Topographic Map Explorer at

http://historicalmaps.arcgis.com/usgs/ 

that allows you to view topographical maps at all scales that were ever produced by the agency, going back to the 1880s.   I pulled up an 1887 map of the Prescott area in the screen shot above.   The sliding bar at the bottom of the search box lets you see what scale maps were generated in what year.   Maps are available for the entire country.

Copper provides the blue color in fireworks

Minerals provide the colors in our fireworks, with copper the source of blue, according to a short informational item posted by the USGS describing what minerals produce other colors, at http://www.usgs.gov/blogs/features/usgs_top_story/the-elements-of-a-dazzling-fourth-of-july/?from=title

Happy 4th of July!

Haboob batters Phoenix

This short video shows the dust storm that hit the Phoenix valley on Thursday night.    The Arizona Republic reports the dust storm and following rain storm knocked out power to 25,000 customers in the valley.

Thousands of Arizona mining maps and files added to online repository

Last month, the Arizona Geological Survey completed another milestone in the digitization of historic mining records from the former Arizona Department of Mines and Mineral Resources. After months of cataloging and geolocating the map collection, we have finally released 5,000 new files (mostly maps) at http://minedata.azgs.az.gov/. The maps reflect the changing nature of mining and exploration in Arizona during the 20th century. Most maps from the early to mid century are of two common varieties. There are plan maps showing mining claims along with geology and surface features. A large number are longitudinal sections of mines underground workings often providing sample locations and associate widths and metallic grades. Later 20th century maps are commonly focused on surface exploration efforts covering large areas. They tend to be maps of land ownership, bedrock geology, alteration, geochemistry and geophysical investigations.   [Right, thumbnail image of map locations available online]

Maps can be searched specifically as a document type from the Search page or found as part of a mine’s complete records when searching on the Map page.

Today, we released more than 800 Arizona records from a donated collection, the James Doyle Sell mining collection. James Sell was a native of Arizona, born in Casa Grande in 1930.  He served the U.S. Army as a radio operator in the Korean War. He was awarded the Korean Service Medal and two Bronze Star Medals. On his return, he studied at the Colorado School of Mines and graduated in 1955. He earned his master's degree from the University of Arizona. He was the Southwest Exploration Manager for ASARCO and retired after 32 years. Sell was a member of the Arizona Geological Society and the Society for Mining, Metallurgy and Exploration.

His collection consists of over 1,800 folders containing geologic reports and mineral exploration data from around the world, but primarily from Arizona and other states in the Southwest. Currently, only those files related to Arizona are online. For a listing of his other files, see http://repository.azgs.az.gov/uri_gin/azgs/dlio/1439

Post by Casey Brown, AZGS Mining Data Project Manager 

M3.9 aftershock to Duncan earthquake

A magnitude 3.9 earthquake that hit just before 4 p.m. today is the largest aftershock so far following Saturday's M5.3 Duncan earthquake near the New Mexico border.   [Right, the main shock and all aftershocks greater than magnitude 3.0,  including the latest event in orange.  Credit, USGS]    As of 7:30 p.m. tonight, 13 people reported having felt this latest aftershock.

We expect aftershocks to continue for weeks and possibly months. 

[note: the initial post had a typo saying the event occurred just before 2 p.m.]

Time lapse video of 2014 Arizona earthquakes

This 20-second time lapse video shows the distribution and relative magnitude of earthquakes in Arizona from Jan. 1 to June 30, 2014. Saturday night's magnitude 5.2 earthquake on the Arizona-New Mexico border stands out. It's so large that it blocks out the 110+ aftershocks that have been detected so far.

Thanks to Arizona Geological Survey Jeri Young for compiling earthquake data and to Jordan Matti for building the video with Microsoft Research's Layerscape software.

Get your geek on - GeoSciML working group in Tucson developing digital data structures

Geoscience researchers from a dozen countries have been meeting at the Lodge on the Desert in Tucson since Sunday, working on the latest developments for the geoscience markup language, GeoSciML.   We're giving them the special Arizona welcome with 108F temperatures and a Saturday night earthquake of magnitude 5.3 right after they settled into the hotel.

GeoSciML has been adopted by a growing number of countries and international data systems "to provide a single, open source, globally agreed data structure that is used to deliver digital geological data over the internet."   

AZGS is hosting the meeting, represented by Geoinformatics Section Chief, Dr. Steve Richard who has been a member of the GeoSciML working group since its organization in 2003.    The group formed under the auspices of the International Union of Geological Sciences, Commission for the Management and Application of Geoscience Information (CGI).

The CGI website notes that "Users of geoscience maps and data know that geological features have no respect for national or provincial borders. Inevitably users of geoscience data will need to source data from more than one data provider. Receiving data in a number of local data formats is recognised as a major impediment to efficient and effective use of data."

The AZGS-led  US Geoscience Information Network (USGIN) is using GeoSciML-Portrayal and GeoSciML to share geological data between government agencies, educational and other organizations, with its biggest application being the National Geothermal Data System.

The group is also working on the use of GeoSciML web feature services and GeoSciML-Portrayal web map services for the 117-nation OneGeology project.

 

Additional seismometer deployed at Duncan earthquake site

We have deployed a temporary seismometer on the a private ranch near Duncan to better detect and locate small aftershocks from Saturday's M5.3 earthquake.

The seismometer is on loan to AZGS and volunteers delivered and installed it.  Thanks also to the landowner for letting us set it up.

Dr. Jeri Young, who runs the Arizona Broadband Seismic Network that operates in conjunction with other stations around the state, is searching the records and calculating accurate locations for the more than 110 aftershocks recorded so far.  Our nearest permanent stations are more than 100 miles from the Duncan epicenter, so the new station should help us detect many more small events and locate them more accurately than we can with the network.

Over 110 aftershocks from M5.3 Duncan earthquake

We have recorded more than 110 aftershocks since Saturday night's M5.3 earthquake near Duncan in southeastern Arizona.  Dr. Jeri Young, who manages the Arizona Integrated Seismic Network at AZSG, says all but five are below magnitude 3.    The USGS interactive map shows events larger than 3.0  [right].    It is unlikely that any of the quakes smaller than M3 would be felt even by people near the epicenter.

Jeri says the network detected ~70 aftershocks in the 24 hours after the main shock, 36-38 in the second 24 hours, and 3 more since then.  We expect aftershocks to continue to occur for weeks and possibly months.

M3.5 aftershock to Duncan earthquake

There was an additional >M3 aftershock on Sunday morning that was not in my previous posts (see orange dot at right).  The main M5.3 event was at about 10 pm on Saturday.

Note that we have upped the magnitude to 5.3 from the initial 5.2.    I'll provide details on that later.

AZGS has recorded a larger number of small aftershocks on our statewide seismic network that we are determining locations for.