Geology and petrology of the Lost Creek barite mine, Union County, Tennessee

Author

Roger T. Steinberg

Date of Award

6-1981

Degree Type

Thesis

Degree Name

Master of Science

Major

Geology

Major Professor

Otto Kopp

Committee Members

Lawrence Taylor, Kenneth Walker

Abstract

The geology and petrology of the Lost Creek barite mine, Union County, Tennessee, were investigated. The uppermost portion of the Mascot Dolomite (Lower Ordovician) and the lower portion of the Dot Formation (Middle Ordovician) are exposed in the Lost Creek area. Rocks of the Lower Ordovician are separated from those of the Middle Ordovician by the Knox unconformity.

The depositional regime for the Dot Formation portion of the Lost Creek section was peritidal (tidal flat and adjacent shallow water marine environments). The carbonate depositional regime of Andros Island, Bahamas, is considered to be a very approximate recent analogue.

Diagenesis of the Dot sediments included many specific events which can be woven into a paragenetic sequence. Most important of these events was dolomitization. Two distinct episodes of dolomitization are recognized. The first (Type I) occurred within a mixing zone of marine and fresh waters. A second episode (Type II) preceded and accompanied mineralization. Type II dolomite can be distinguished by its coarse grain size, luminescent zonation, and ferrous iron content. Much of the Type II dolomite occurs as void- or vug-fillings.

At Lost Creek, mineralization consists of barite with minor sulfides (pyrite, marcasite, sphalerite, galena, and chalcopyrite) and is associated with brecciation and Type II dolomitization. Unlike other Mississippi Valley-type deposits in east Tennessee, brecciation and mineralization are not confined to Lower Ordovician rocks but extend into basal Middle Ordovician beds. Mineralization within the Middle Orodvician Dot Formation can be considered a diagenetic event, and was probably even syngenetic in part.

Mineralization, at least some brecciation, and Type II dolomitization resulted from mixing of the mineralizing fluids with formational waters (which themselves were the product of the earlier mixing of fresh and marine waters). Barite deposition may have been controlled by the cooling and oxidation of the sulfide-rich ore fluid by the formational solutions.

Recommended Citation

Steinberg, Roger T., "Geology and petrology of the Lost Creek barite mine, Union County, Tennessee. " Master's Thesis, University of Tennessee, 1981.
https://trace.tennessee.edu/utk_gradthes/15304