Geologic map and geologic hazards of the Three Points Quadrangle, Pima County, Arizona

Resource Abstract:

This report and maps describe the geology, geomorphology, and geologic hazards inthe Three Points quadrangle, on the southwestern fringe of the Tucson metropolitan areain unincorporated Pima County (Figure 1). The map area is located in the transitionbetween the upland, moderately dissected Altar Valley to the south and the broad,undissected basin called Avra Valley to the north. The community of Three Points (alsocalled Robles Junction) lies on the approximate boundary between these two geographicareas. The map includes a nine-mile-long reach of Brawley Wash, which cuts through themap area from southwest to northeast. Brawley Wash heads just south of the U.S. Mexico border and drains all of Altar and Avra valleys before joining the Santa CruzRiver northwest of Tucson. About 60 percent of the Three Points quadrangle consists ofthe northwestern piedmont of the Sierrita Mountains. The quadrangle also includes asmall part of the northwestern piedmont of the Coyote Mountains and the southern fringeof the Roskruge Mountains. The quadrangle is generally undeveloped, and is currentlyused primarily for grazing. Some low-density suburban development has occurred aroundthe community of Three Points and on the Sierrita and piedmont to the south. Much ofthe floodplain and terraces of Brawley Wash has been developed for agriculture. TheThree Points quadrangle will likely experience much more urban/suburban developmentin the next few decades. This map and report may be of use in avoiding or mitigatinggeologic hazards in this area. (21 pages)

Citation

Title Geologic map and geologic hazards of the Three Points Quadrangle, Pima County, Arizona

publication  Date   2000-10-01T12:00:00

cited responsible party - originator

individual Name Pearthree, P.A.

organisation Name  missing

position Name missing

Contact information

Address

electronic Mail Address metadata@usgin.org

cited responsible party - originator

individual Name Ferguson, C.A.

organisation Name  missing

position Name missing

Contact information

Address

electronic Mail Address metadata@usgin.org

cited responsible party - originator

individual Name Gilbert, W.G.

organisation Name  missing

position Name missing

Contact information

Address

electronic Mail Address metadata@usgin.org

cited responsible party - originator

individual Name Skotnicki, S.J.

organisation Name  missing

position Name missing

Contact information

Address

electronic Mail Address metadata@usgin.org

cited responsible party - pointOfContact

individual Name Missing

organisation Name  Arizona Geological Survey

position Name missing

Contact information

Telephone

Voice 520-770-3500

Address

416 W. Congress St., Suite #100, Tucson, AZ, 85701-1381 Country USA

electronic Mail Address michael.conway@azgs.az.gov

Linkage for online resource

URL: http://www.azgs.az.gov

protocol http

Topic Category:  geoscientificInformation