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Charles A. Ferguson
Research Geologist

ATTN: Charles A. Ferguson
1955 E. 6th St.
PO Box 210184
Tucson, Arizona 85721

Phone: 520-621-2470





  • B.S., University of Kansas
  • M.S., New Mexico Tech
  • Ph.D., University of Calgary


Dr. Ferguson is a structural geologist with an extensive background in volcanology, sedimentology, and stratigraphy.  Interpreting the structural and eruptive history of volcanic fields throughout the southwest has become a specialty by default.  Using a somewhat novel approach to mapping volcanics that involves an emphasis on phenocryst mineralogy rather than volcanic textures, Ferguson, along with principal mapping colleagues Robert Osburn, Steven Skotnicki, Wyatt Gilbert, Bradford Johnson, Shari Kelly, Stephen Enders, and geochronologist Bill McIntosh have unraveled the structural and eruptive histories of several, previously poorly understood volcanic fields.  Principal examples include the Superstition, Kofa, Morenci, Tucson, Sierrita, and Mt Fagan fields in Arizona, and portions of the several other smaller fields in Arizona and New Mexico.  Ferguson has also worked extensively in the Jemez, and northern Mogollon-Datil volcanic fields of New Mexico.

Ferguson’s experience with volcanic rocks, gained chiefly during his Masters thesis research at New Mexico Tech and as a chief field assistant with Sam Bowring in the Paleoproterozoic Great Bear magmatic zone of northern Canada, has lead him to teach a semi-formal intensive short course for advanced students and industry geologists that dispels numerous myths regarding how to map and interpret volcanic rocks.  The course, entitled “Whole Lava Love” exposes students to the wide variety of volcanic textures that are commonly used inappropriately by many geologists as the chief defining criteria for mapping and defining volcanic units.  The course forces students to recognize the folly of the traditional classroom-based approach, and teaches them to approach volcanic units as stratigraphic entities whose magmatic origins are better defined by composition (phenocryst assemblages) rather than superficial appearance.

Ferguson’s main interest and first love in geology is, however, compressional mountain belts.  His interests have taken him from the Mackenzie Mountains of northern Yukon and the Katmai volcanic arc of southwestern Alaska to the Ouachita fold-thrust belt in the mid-continent, and many areas in between.  His Ph.D. research at the University of Calgary in one of the world’s most impressive fold belts deep within the metamorphic internides of the Canadian Cordillera involved detailed study of slaty cleavage, a phenomenon that his fascinated geologists for over 3 centuries.  More recently, Ferguson has worked on several widely scattered, thick-skinned, Laramide compressional belts in northern New Mexico and southern Arizona where his mapping has revealed heretofore unrecognized multiphase fold patterns the have profound implications to our understanding of the formation of the Rocky Mountains.

Ferguson’s most recent project, in collaboration with Pulitzer Prize winning author E. Annie Proulx, is an essay on the geology of Wyoming’s Red Desert.  During research for this project, Ferguson uncovered inconsistencies regarding the Plio-Pleistocene history of the Red Desert that tie in directly with colleagues Jon Spencer, Kyle House, and Phil Pearthree’s recent research involving the geomorphic and geologic history of the Colorado River and formation of the Grand Canyon.  Ferguson’s Wyoming research may provide an important missing link to explain how the Colorado River suddenly and rapidly incised the Grand Canyon approximately 5 million years ago.