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Bighorn Fire smoking the Catalina mtns.

Geology & Mineral Resources of the Santa Catalina Mountains, SE Arizona

145-page monograph on the geology and mineral resources of the Santa Catalina Mtns. by Dr. Eric Force, US Geological Survey (retired)

The lightning-caused Bighorn Fire has scorched nearly 85,000 acres in the Santa Catalina Mountains from 5-26 June 2020. On a more positive note, Dr. Eric Force, formally of the U.S. Geological Survey, provided the AZGS with permission to upload his monograph, ‘Geology and mineral resources of the Santa Catalina Mountains, southeastern Arizona’ to the AZGS Document Repository.

The 145-page report was originally published in 1997 and includes 117 figures, 15 tables, and 2 large-format geologic map plates (Figure 1). The Table of Contents is reproduced at the end of this blog. The monograph was published by the University of Arizona Center for Mineral Resources in 1997 under the direction of Dr. Mark Barton.

From page 6 of Force’s ‘This Study’ section,
 “Field work for this study was conducted intermittently from 1989  through 1992; approximately 160 days were spent in the field. Except in a few circumstances, the work consisted of traverses with side excursions, i.e. contacts were generally not walked. Thus the map is
still of a reconnaissance nature and a better job could be done.

Geophysical coverage was insufficient to be of much help. The geologic map (pl. 1; 1:48,000), though quite conventional in most respects, needs explanation in a few others. Where a protolith has been recrystallized and/or deformed, the protolith is nevertheless the mapped unit. The extent of mylonitization and some other varietal information is shown in. plate lB. Where an igneous unit has intruded another rock unit, the intrusive is the mapped unit where it comprises over 50 percent of the area, unlike the procedure locally followed by Banks (1974).

To the extent possible, structures of different ages are coded  separately on the maps. Concealed contacts are extended into plutons as well as under cover. The cross sections are oriented NNE-SSW, sub-parallel to the direction of mid-Tertiary tectonic transport, to aid tectonic reconstruction. Plate 2 (1:12,000) shows the geology of some areas in greater detail.

No stratigraphic sections were measured in this study. Thicknesses are taken from the maps and cross sections except where measured thicknesses from previous studies are quoted.”

Force, E.R., 1997, Geology and mineral resources of the Santa Catalina Mountains, southeastern Arizona: a cross-sectional approach. University of Arizona Center for Mineral Resources, Monograph in Mineral Resource Science, 145-p, two map plates.

Acknowledgments. We thank Dr Eric Force and Dr. Mark Barton for providing making this excellent geologic resource available to Arizona’s geosciences community.

Plate 1
Figure 1. Partial copy of Plate 1 of Eric Force's Santa Catalina monograph.

Table of Contents

Table of contents