Whetstone Mountains - GeologyCochise College
Geology of Southeastern Arizona
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Whetstone Mountains - GeologyRoger Weller, geology instructor
wellerr@cochise.edu last edited: 10/11/07
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.
Fossils
from the Whetstone Mountains
Published
references on the geology of the Whetstone Mountains
Stratigraphic Section in the Whetstones- from Southern Arizona Fossils