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Top Geology-related stories in Arizona 2015

Article Author(s): 

Michael Conway

In 2015, a 250-ton rock slab threatened to crush a power plant at Glen Canyon Dam, an earthquake rattled the Phoenix metropolitan area, and the Tucson Gem, Mineral and Fossil show fueled the Tucson economy to the tune of $120 million. And these were a just a few of the notable geology-related stories that impacted Arizona in the past 12 months.

The Arizona Geological Survey (AZGS) staff perused geologic events of the past year and selected those below as some of the top geology-related stories in Arizona. The stories range widely from geologic hazards, to Arizona’s national and international ranking as a jurisdiction amenable to mining, to the precipitous decline in copper prices. 

Stories are in rough chronologic order from latest, copper prices retreat to ~ $2 per pound in December 2015, to earliest, Arizona was #1 in U.S. in non-fuel mineral mining in 2014.

Did we miss a story? Undoubtedly! What geology story would you have included?

Copper prices tumbleCopper Prices, oh my! Global copper prices tank, falling to the ~ $2 per pound level and pitching Arizona copper mining into a tailspin; in response to the weak market, Freeport-McMoRan announced they would close their Sierrita Mine. The good news? Copper will come back as the global economy rebounds and as nations continue to migrate to green energy. Earlier in the year, Governor Doug Ducey signed legislation naming copper as the official metal of Arizona. Graphic by

Geologic hazards in ArizonaMy Turn – Geologic Hazards in Arizona. "Earthquakes threaten Arizona (and that's not all)," an op-ed piece by AZGS Director Lee Allison on geologic hazards appeared in the November 15 edition of the Arizona Republic. It followed in the wake of the magnitude 4.1 earthquake that rocked Phoenix. Dr. Allison described many of the geologic hazards that threaten Arizona: earthquakes, landslides, wildfires, floods and earth fissures. He called for a comprehensive solution involving surveying, monitoring and better construction.

Earthquake in PhoenixEARTHQUAKE shakes Phoenix! On November 1, 2015, Phoenix was rocked by a magnitude 4.1 earthquake originating north of Black Canyon City. Ground shaking was widely felt across the Valley of the Sun, and as far north as Flagstaff and south to Casa Grande, Arizona. Thousands alerted the U.S. Geological Survey (USGS) through its online “Did you feel it” survey tool, but it’s probable that 100,000s to millions of people felt the ground move. Media in the Phoenix-area followed the event closely and AZGS staff responded to more than a dozen inquiries about this earthquake and the likelihood of other damaging earthquakes in Arizona.

Glen Canyon damLook Out below! In October, a 250-ton slab of Navajo Sandstone peeling off the south wall of the canyon at Glen Canyon dam was bolted into place to prevent it from falling on to power plant facilities immediately below. This photo shows the slab in the lower left area of the circle below with dozens of dark circles marking the rock bolts. An official at the dam said plans are in place to remove small pieces of the slab over time to eliminate the threat. (From Arizona Geology Blog.)

Aggregate mapAZGS pioneers mapping aggregate resources. AZGS released its first geologic database for aggregate resource assessment for the Phoenix metropolitan area. This map product should inform local and county planning and zoning authority decisions as they address SB 1598 (2011) regarding conservation and management of aggregate resources.

Sustainable mining?Sustainable Mining? University of Arizona & UNAM take the lead. The University of Arizona and UNAM form the vanguard in striving for sustainable mining models in the 21st century. The University of Arizona Global Initiatives Group joined by UA Mining & Geological Engineering Department and colleagues from UNAM in Mexico hosted a 3-hour symposium "Mineral Resources: from Exploration to Environmentally Sustainable Mining in the SW United States and NW Mexico." (AZ Mining Review October issue)

Gold King Mine mapWhat’s in a map? In collaboration with federal and state agencies, AZGS built and launched the interactive Gold King Mine Spill water sampling map that displays sample sites linked to data for water chemistry samples from the Animus River, San Juan River and Lake Powell. The spill adversely impacted portions of Colorado, New Mexico, Utah and Arizona, and tribal lands of the Ute and Navajo people. The Gold King Mine map informs stakeholders, decision makers and the public regarding sampling and water quality status.

Natural Hazards in ArizonaLandslide inventory program kick off! AZGS launches the state’s first comprehensive landslide inventory program. Over the past year, our environmental geology section has identified more than 6,000 landslide masses, greatly improving our knowledge base of the distribution of landslide occurrences in Arizona. This should, in turn, inform landslide hazard assessment and mitigation going forward. Look for the results to appear on our interactive Natural Hazards in Arizona viewer in 2016.

Bill DickinsonFamed geologist dies. William (Bill) Dickinson, Professor Emeritus in the UA Department of Geosciences, passed away on 20 July while on an archaeological field trip to Nuku'alofa, Tonga. Dr. Dickinson was a pioneer in the plate tectonic revolution.  "Bill Dickinson was a bigger-than-life guy in a bigger-than-life place," said his close colleague George Davis, UA Regents' Professor Emeritus of geosciences (from UA News, 27 July).

AASG -- State geologists in FlagstaffState Geologists descend on Flagstaff. AZGS hosted the 107th Annual Meeting of the Association of American State Geologists (AASG) in Flagstaff in mid-June. Over 150 people attended including active and former state geologists, their guests, and USGS staff led by Acting Director Suzette Kimball.

Gem, Mineral and Fossil show feeds Tucson economy. In February 2015, Tucson News Now reported that direct spending during the two-week 2014 Tucson Gem, Mineral and Fossil showcase topped $120 million. The Tucson Gem and Mineral Society kicked off this world-class mineral, gem and fossil event 61 years ago. The 2016 show marks the 62nd consecutive year.

Arizona is #1 mineral producing stateArizona moves up in the ranks! In February 2015, the Fraser Institute’s 2014 survey ranking of jurisdictions worldwide for their favorability for mining showed a marked increase in Arizona’s standing from 2013. Arizona ranked 18th in the world and 6th in the U.S. in investment attractiveness, moving up 4 places from last year. We slipped 4 places in "policy perception," due to federal land management practices. And Arizona jumped dramatically from 25th to 12th in "best practices mineral potential." We ranked 20th in "current mineral potential," behind only Nevada and Wyoming in the US. (Modified from Arizona Geology Blog of 27 February.)

Arizona is #1!  In January 2015, Arizona was recognized as the #1 mineral-producing state (non-fuel) in the U.S. for 2014. The 2015 Mineral Commodities Summary reports that Arizona produced $8.06 billion worth of minerals in 2014, or 10.38% of all non-fuel minerals in the nation, with the principal minerals being, in order; copper, molybdenum concentrates, sand and gravel (construction), Portland cement, and crushed stone. Nevada was a close second with $7.490 billion or 9.66% of the national production.

Chief, Geologic Extension Service
AZ Geological Survey

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