This summary report overviews a State of Arizona and U. S. Department of Energy funded drilling project to determine if near-term hot dry rock (HDR) geothermal potential exists in the eastern portion of the White Mountains region of Arizona. A 4,505 feet deep slim-hole exploratory well, Alpine1/Federal, was drilled within the Apache-Sitgreaves National Forest at Alpine Divide near the Alpine Divide camp ground about 5 miles north of Alpine, Arizona in Apache County (Figure 1). A comprehensive technical report, in two parts, details the results of the project. Part 1, Alpine1/Federal, Drilling Report, discusses the drilling operations,
logging program, permitting and site selection for the hole. Part 2, Temperature Gradients, Geothermal Potential, and Geology, summarizes the temperature gradients, heat flow, geothermal potential, and subsurface geology.

In March 1971, the Arizona Bureau of Mines—predecessor of today’s Arizona Geological Survey—published the first issue of Fieldnotes. For nearly 40 years, Fieldnotes, and its successor, Arizona Geology, showcased all things geologic in Arizona. From the onset, the quarterly magazine printed topical pieces on Arizona’s mineral resources, energy potential, and environmental geology. In Fall 1988, Fieldnotes became Arizona Geology, and the newsletter was retailored to meet the needs of Arizona’s exploding population. There was increased focus on articles describing geologic phenomena—flash floods and regional floods, earthquakes, landslides, volcanism, swelling and shrinking soils, earth fissures, and more—with the most immediate and adverse impact on the lives and properties of our fellow Arizonans. But that was then and this is now! As print publication costs rise through the stratosphere, we simply can no longer afford to print and mail 4100 copies of Arizona Geology quarterly. Arizona Geology is going digital. We are suspending the print publication immediately and we are moving from a quarterly schedule to three times annually.

The purpose of this research project is to determine the origin of the materials used to construct the Black Hills Dam in order to restore the landscape to pre-dam conditions. The Black Hills Dam site is located in northern Scottsdale, Maricopa County, at 33.75° North, 111.80° West. The goals of this project are to characterize the surficial deposits and local geology of the dam site. This report presents our findings, interpretations and conclusions based on background research, a site visit to the dam site, and technical discussions with the City of Scottsdale engineer and planners.

This open-file report describes the carbon-sequestration potential at the site of the 1 Alpine-Federal geothermal test drill hole, which is located south of Springerville in central eastern Arizona near the New Mexico border. A previous report, Arizona Geological Survey (AZGS) Open-File Report OFR 94-1, version 2.0, describes the subsurface geology encountered in the 1 Alpine-Federal well in much more detail than this new report.

This report details geothermal resource exploration done for Arizona Public Service and the U.S. Department of Energy in 2005 to evaluate the geothermal resources of the Clifton Hot Springs area in Greenlee County, eastern Arizona for electric power production. The intent of the evaluation was to determine the local geologic controls of the geothermal system and, using publicly available data and original mapping performed for this project, to recommend locations for Controlled Source Audiomagnetotelluric (CSAMT) cross sections. The results of the geophysics were then combined with the geologic mapping to site three gradient holes, two of which were drilled to depths of 635 feet and 1,000 feet, respectively.

This white paper has been created by Arizona Land Subsidence Group to help educate stakeholders and decision makers by describing the geological features and processes of land subsidence and earth fissures, and the hazards they create. This paper presents the current and future technical needs that exist in terms of basic knowledge, available data, and the state of professional practice.

To provide insight into provenance relations for multiple mid-Oligocene to mid-Miocene subbasins
(typically half-grabens) dissected by erosion in uplands lying north of the Catalina core complex and west of the San Pedro trough, 136 outcrop counts were made of clast types in tilted conglomerates of the Cloudburst and San Manuel Formations and their lateral equivalents in exposures as far north as the Gila River near Kearny. Clast counts were not made for younger conglomerates of the post-mid-Miocene Quiburis Formation, which fills the San Pedro trough and onlaps flanking uplands (Dickinson, 1998), because Quiburis clast assemblages in all cases match bedrock sources exposed uphill on the modern landscape. By contrast, paleotopography during Cloudburst and San Manuel deposition can only be inferred from local paleocurrent indicators (clast imbrications; figure 39 of Dickinson, 1991, p. 70-71) and clast assemblages in tilted strata. Areas included in this study were the Guild Wash allochthon between the Tortolita and Suizo Mountains, the Star Flat allochthon on the east flank of the Black Mountains, the
Black Hills (west of Mammoth), Camp Grant Wash (and Putnam Wash) between the Black Mountains and the Black Hills, multiple drainages of the Tortilla Mountains (Eagle Wash, Jim Thomas Wash, Hackberry Wash, Indian Camp Wash), and Ripsey Wash on the west flank of the Tortilla Mountains (Figs. 1-4).

A brief reconnaissance (5-8 November 2008) of the Big Sandy Formation near Wikieup (on US Highway 93 in Mohave County, Arizona) was undertaken to reconcile a reported dominance of lacustrine beds (Sheppard and Gude, 1972, 1973) with the largely terrestrial mammalian fauna reported from the formation (MacFadden et al., 1979; Lindsay and Mead, 2005). The issue is resolved satisfactorily by appreciation that nearly all fossil localities occur in fluvial beds that intertongue with and grade laterally into the dominant lacustrine strata.

At the request of the U.S. Forest Service to Red Rock Jeep Tours of Sedona a geologic report on the condition of the Devils Kitchen sinkhole was required for the safe continuation of Jeep visits to the site (Fig. 1). Mark Avery of the jeep company contacted me to study the site and write up my findings. The study of sinkholes in the Sedona area has been of interest to the writer for some time and the present study is hoped to shed some light on these fascinating geologic features. This report is offered as a public contribution at the cost of publication and without fee.