SUGGESTED CORRELATION OF POSSIBLE HYDROTHERMAL ORIGIN OF KARST IN EARLY MISSISSIPPIAN ROCKS

The interpreted origin and nature of most karst, and particularly origin of caves has largely centered around shallow processes and the interactions of meteoric water, rapid recharge and circulation of groundwater. Klimchouk (2007) opened up the discussion about hydrothermal origins of many caves. Others show e.g., in the Guadalupe Mountains and Black Hills, that geothermal process are involved and are the primary mechanism.

Some caves have vein ore deposits in them that have been documented but generally there are few rigorous discussions about both being related. However, as many caves may not seem closely related to metalliferous ore deposits, but may have features that have been altered and modified after subaerial exposure. In “conventional” karst research few deviations are made into understanding the paleogeography and mineralogy of the bedrock.

Exploration for ore deposits, has sometimes intersected existing caves, because many host rocks are carbonates. In addition, many caves have forms that suggest both conventional and hydrothermal origins.

The result is that understandably there are both complimentary and conflicting interpretations and discussions about whether cave systems are likely related to having formed by geothermal processes. Another complication, is that karst as it appears today maybe paleokarst - that was not widely recognized as such before.

Early Mississippian/Carboniferous rocks and several caves and karst formed therein across the globe maybe related. I show several that are in same stratigraphic sections despite being distant today, but paleogeographically are related. If these are geothermal in origin, as they appear to be, an intriguing question is: in terms of continental tectonic history, which magmatic processes may have played a part and what is their origin? An outrageous explanation is that they are affected by subducted walls of, e.g., the Farallon Plate, that have passed beneath the drifting North American Plate from 250 Ma to the present.