A new earth fissure near Wintersburg, Maricopa County, Arizona

A new earth fissure has been reported southeast of Wintersburg, about 75 km (50 miles) WSW of Phoenix (Figure 1). The fissure was reported to AZGS in early September and was visited several times through early November. Field mapping was done with a hand-held GPS. This fissure appeared over the past summer, probably during a heavy rainstorm in July. The earth fissure and adjacent desiccation cracks are plotted on a topographic base (Figure 2) and an aerial photo base (Figure 3). The fissure is nearly north-south and is 307 m (1007 ft) long (Figure 4). The fissure is very young, with narrow, steep sides and a highly irregular apparent depth ranging from 8 feet over short distances. In two locations the fissure is en echelon (Figure 5), with NW-SE steps. There is no discernable vertical offset across the fissure.Documents in the AZGS Document Repository collection are made available by the Arizona Geological Survey (AZGS) and the University Libraries at the University of Arizona. For more information about items in this collection, please contact azgs-info@email.arizona.edu