Study Area Maps (1:12,000 - 1:24,000 Scale)
“Look, this (earth fissure) is a hazard. It’s going to bite you if you don’t know that it’s there;
it’s like a snake. Someday, it’s going to bite somebody, and it’ll bite them hard ….”
-Geoscience consultant Herb Schumann on earth fissures
as reported in the East Valley Tribune, February 2006.
The arid valleys of central and southeastern Arizona are home to earth fissures: a geologic hazard that threatens people, property, infrastructure (e.g., roads, gas lines, canals), and livestock. To reduce the societal risk of this growing geohazard, the Arizona Geological Survey (AZGS) combines detailed mapping of fissures with an aggressive educational outreach and map dissemination program.
This webpage contains links to 1:12,000- or 1:24,000-scale maps of earth fissure study areas located in Cochise, Maricopa, Pima, and Pinal counties. We identified and demarcated the 23 study areas during the 2006-2007 planning stage of AZGS’s Earth Fissure Mapping program. Detailed mapping of the study areas began in 2007 and is expected to take four years to complete the first pass through all areas.
See the right sidebar for a link to maps of completed study areas. Mapping of other study areas are underway. As we complete mapping of a study area, a link to the finished map product will be added here. Additionally, the Arizona Department of Real Estate will provide an interactive earth fissure viewer hosted by the State's internet map server (IMS).
To assist the public and civil authorities in accurately locating earth fissures, each map is constructed on a shaded relief background – accentuating local topography – with an up-to-date road network.
Each map contains an identical map legend with symbology denoting the status of individual fissures – continuous, discontinuous, or reported but unconfirmed.
AZGS Earth Fissure Mapping Procedures
Mapping earth fissures is challenging and time consuming. In each study area, we begin by reviewing earlier maps and technical reports, examining new and historical aerial photographs, and consulting with geoscientists and engineers in agencies (e.g. Salt River Project, AZ Dept of Water Resources) or companies with expertise or information on fissures.
Once we narrow down the known or suspected general fissure locations , we travel to the study area, where we identify, examine, characterize, and map each earth fissure using high-precision global positioning system (GPS) receivers. To assure a consistently high quality map product, we collect data every 5-15 feet (about 2- to 4-meters), yielding 300 to1,000 data points per mile (about 250 to 500 data points per kilometer) of fissure! Interested in the nature of the data we collect?
Finally, we return to the lab, where the field data are processed, reviewed for adherence to set standards, and placed in a geographic information system (GIS) map environment.
AZGS Earth Fissure News Release (03.15.11)
AZGS Earth Fissure News Release (12.22.09)
AZGS Earth Fissure News Release (01.07.09)
AZGS Earth Fissure Brochure 2008
AZGS Earth Fissure Report, 2007 (OFR 08-02)
Arizona's Earth Fissure Mapping Program: Protocols, Procedures and Products (OFR-08-03)
AZGS Earth Fissure Report, 2006 (OFR 07-01)