Whetstone Mountains - Geology
Cochise College    
Geology of Southeastern Arizona
Geology Home Page

Roger Weller, geology instructor

wellerr@cochise.edu    last edited:  10/13/16

East side of Whetstone Mountains, Cochise County, Arizona


general geology

The northern third of the Whetstones consists of some Precambrian granite with small amounts of Cretaceous sandstones, shales, and conglomerates on the north flank of the mountains in fault contact with the granite.


The southern part of the mountains is a fairly complete tilted section of Paleozoic and early Mesozoic sediments.  Exposed, and going generally from North to South, are the Cambrian Bolsa Quartzite and Abrigo Limestone formations, the Mississippian and some Permian limestones, shales, and sandstones.  There are also rhyolite flows, tuffs, and sediments that are intruded by a small stock of Laramide granite containing a pod of Permian limestone and shale.


As in all of southern Arizona, there are no Late Ordovician or Silurian rocks in the section.  In general, the stratigraphic record also shows that the marine deposition of the Paleozoic was abruptly terminated in Middle Permian time, to be replaced by continental deposits during Mesozoic and Cenozoic times. 


   Maps of the Whetstone Mountains

   Views of the Whetstone Mountains 

   Fossils from the Whetstone Mountains

   Published references on the geology of the Whetstone Mountains 

Stratigraphic Section in the Whetstones- from Southern Arizona Fossils