A workshop on the future of research on mineral resources in Arizona was held on January 12 and 13, 1987, in Tucson, Arizona. The objective was to exchange information from research on the geology of metallic mineral resources. The emphasis was on the potential for the discovery of new ore deposits and on the type of research necessary to fulfill that potential. We recognized at the outset that copper and associated metals derived from porphyry-type deposits related to calc-alkaline igneous rocks have dominated and most likely will continue to dominate metallic mineral production in Arizona. We also recognized that a large research effort has been devoted and will continue to be devoted to the understanding of these traditional deposits. As a result, the potential for other deposit types has largely been neglected. The decision was made to emphasize those geologic environments in which "nontraditional" deposits might be found. The term "unconventional" used in the workshop title simply means "nonporphyry copper deposits." 16 pages.

The geology of the Mormon Flat Dam Quadrangle is dominated by a thick succession of Miocene volcanic rocks, and by the consequences of two important structural events: 1) formation of the Superstition Cauldron at approximately 18.6 Ma (McIntosh, personal communication, Ferguson and others, in preparation), and 2) regional extension which was active for a short period of time directly before, during, and after eruption of the Apache Leap Tuff. The Tertiary stratigraphy consists of three broadly defined sequences: 1) pre-cauldron lavas, 2) syn-cauldron units - chiefly Apache Leap Tuff, and 3) post-cauldron lavas, intrusions and volcaniclastic sedimentary rocks. Regional extensional tectonism was active over a broad area south of the Salt River Canyon during formation of the pre-cauldron lava field (between approximately 20.5 Ma and 18.6 Ma), and then for a short time after cauldron formation, along a narrower zone along the Salt River. Areas lying to the north of Salt River remained relatively stable and unextended throughout the history of the volcanic field. Report and geology of the Mormon Flat Dam Quadrangle, Maricopa County, Arizona, three sheets, scale 1:24,000.