Since 2007, AZGS has systematically mapped and monitored earth fissures in Cochise, La Paz, Maricopa, Pima and Pinal Counties.
Cochise, La Paz, Maricopa, Pima and Pinal Counties
Area of Study
Earth fissures result from basin subsidence driven by groundwater pumping in agricultural areas of western, central and southeastern Arizona. Fissures are an anthropogenic geologic hazard and threaten people, property, livestock and infrastructure. Effective management of fissures is a costly and labor-intensive task.
In 2006-2007, the AZGS initiated systematic identification, mapping, and monitoring of earth fissures. Map data illustrating the distribution and location of fissures are available at the interactive Natural Hazards in Arizona Viewer. The viewer is updated annually or bi-annually to include new fissures or areal changes (lengthening or coalescing) of existing fissures.
For a primer on subsidence and earth fissure formation: Land Subsidence and Earth Fissures in Arizona by Steve Slaff.
More from AZGS
June 14, 2018
Monsoon season means fresh earth fissure activity
The onset of the 2018 monsoon season is just days away. Sheet flow from monsoon rains is a chief mechanism for initiating earth fissure activity. In summer 2017, we saw some substantial fissure activity in Cochise and Maricopa County.
Today, AZGS staff drafted and disseminated a short note to civil authorities (emergency management, roadway and flood districts) in a five county area regarding the importance of our joint efforts to track new fissure activity.Alert
Earth fissure activity in a five county area, Cochise, Maricopa, La Paz, Pima and Pinal Counties increases with the onset of Arizona's monsoon season.
March 08, 2018
Fresh fissures spotted in McMullen Valley, AZ
Ken Fergason with AMEC-Foster-Wheeler spotted fresh earth fissures near Wendon, AZ on Google Earth Imagery. The fissures align well with AZ Dept. of Water Resources (ADWR) InSAR images, but they are small relative to measured subsidence along McMullen Valley; it makes me wonder why we don’t have more fissures there. The exposed fissures may be the onset of a fissure swarm, such as we observe along the western flank of the Picacho Mountains in Pinal County.
Brian Conway with ADWR will be out there at some point soon to do some survey control and he said he would check these out. I found some additional incipient fissures in GE nearby.
Image - InSAR interferometry image illustrating subsidence of McMullen Valley in La Paz County, Arizona.
Posted by Joe Cook.
January 29, 2018
Earth fissure repairs on Cochise Stronghold Rd.
Cochise County authorities scheduling repairs to Cochise Stronghold - Dragoon Rd intersection on 31 Jan. Joe Cook (AZGS) captured this picture along Cochise Stronghold on 10/19/2017.Alert
Caution! Cochise County reports earth fissure damage near the intersection of Dragoon Rd. and Cochise Stronghold Rd.
November 29, 2017
Revised Earth Fissure Maps Released
In Nov. 2017, we released updated versions of Earth Fissure Study Area maps for:
- Tator Hills, Pinal County
- Chandler Heights, Maricopa & Pinal Counties
- Apache Junction, Maricopa & Pinal Counties
An updated 'Mapped Earth Fissure Traces in Arizona' (v. 11.06.2017) GIS database is available, too.