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And the Survey Says ...Mapping earth fissures isn’t a topic that comes up very often, unless you’re in the halls of the Arizona Geological Survey, which celebrates its 125th anniversary this year.
By Kayla Frost
What began as a lot of work with no pay for one man, John F. Blandy, would ultimately become the Arizona Geological Survey. In 1888, Blandy was appointed Arizona’s Territorial geologist, a position created five years after Governor Frederick A. Tritle asked Congress to establish a geological survey for the Arizona Territory.
One of Blandy’s duties was to collect mineral-production statistics, and it wasn’t always easy. “Blandy complains that miners of this section are negligent about forwarding to him the information recently asked for,” according to a March 1890 article in the Arizona Weekly Journal-Miner, perhaps nudging the miners of Yavapai County into action.
But things finally fell into place, and, since Blandy’s tenure, the position of Territorial geologist has evolved into the University of Arizona Bureau of Mines, then the Arizona Bureau of Mines, then the Arizona Bureau of Geology and Mineral Technology. Finally, in 1988, the agency became the Arizona Geological Survey.
This year, the survey celebrates its 125th anniversary, which makes it only nine years younger than the U.S. Geological Survey. Arizona’s survey is in charge of fine-scale geologic mapping and hazard analysis, says Michael Conway, chief of the agency’s Geologic Extension Service.
The AZGS excels at mapping earth fissures, which result from water-table depletion. As groundwater is removed, loose sediments collapse because “the water is partly responsible for holding the ground up,” according to the USGS. Sometimes, areas collapse at different rates, causing cracks in the Earth’s surface.
Fissures can cause extensive damage to property and infrastructure. To help homeowners, real estate agents, conservation advocates, and city and water planners, the AZGS provides online, interactive maps of the state’s fissures.
“We’re the only show in town for that,” Conway says.