The Upper Arkansas Geological Association is holding a talk at the Sangre de Cristo Electric community room, at 7 p.m., Thursday, Nov. 9. It will be given by Peter Barkmann of the Colorado Geological Survey and will present new geologic mapping and discoveries on his recent work in South Park. The talk will be of interest to geologists, rock hounds, collectors and anyone who might want to learn what you may be looking at as you drive through South Park on U.S. 285.
South Park holds many geologic wonders as well as remarkable natural resources. For nearly 140 years geologists have continued to unravel the complex mysteries of this inter-montane structural basin.
Evidence points to an underlying structural fabric developed by Precambrian plutonism, metamorphism and tectonism that reactivates time and time again through subsequent tectonic upheavals, each with its own unique set of stress and thermal conditions. South Park straddles the eastern edge of the Pennsylvannian-Permian central Colorado trough and was later the focus of intense contractural deformation during the Late Cretaceous into Paleogene Laramide orogeny. Volcanism overwhelmed the region through the late Paleogene and subsequent, post-Laramide extensional features overprint the already complex structural and stratigraphic fabric.
This geologic evolution has left behind many important resources including hard rock base and precious metal deposits, sedimentary coal and petroleum resources, as well as uranium resources. The geologic fabric also provides the framework for geothermal energy. Not to be overlooked are many occurrences of petrified wood, fossils, as well as a variety of collectable minerals from pegmatites and sedimentary deposits.
Fred Henderson, UAGA