Stability of paleosinks and karstic carbonates in the Southern Fire Clay Mining District of Missouri

Author

Robert Weiser Dillon

Abstract

"The Southern Fire Clay District of Missouri was intensely mined during the late-1800’s to mid-1900’s for its valuable resource of high refractory clays deposited within Pennsylvanian sinkholes “paleosinks”. Mining operations have produced modifications in the Ozark aquifer, which in effect has possibly increased the instability of this paleokarst terrain and the potential of further environmental impacts to the land. Evidence supporting this hypothesis are: (1) A southerly shift in the regional groundwater divide relative to the topographic divide. This possibly is caused by the distribution of leaking clay pits, which suggests that the bedrock permeability or hydraulic conductivity has been increased towards the north. (2) Stratigraphic and geohydrologic unites thin in areas related to clay pit distribution. It is speculated that meteoric water is being recharged through paleosinks and is causing further dissolution along fractures, carbonate bedding planes and paleoconduits. (3) Clay pits are interconnected and are possibly undergoing enhancement of secondary permeability in the subsurface. This hypothesis is supported by missing (dissolved) rock sections in water wells, seismic data, obvious pit drainage of collapsed clay pits, and connective dye trace evidence. (4) Seismic reflection data of paleosinks and field observations of known collapsed clay pits show a potentially unstable setting in the vicinity of clay pits. (5) Clay pits in-filled with refuse and unconsolidated material show evidence of recent subsidence. Many clay pits filled with water leak into the subsurface and have the potential for catastrophic collapse. Open pits and unplugged boreholes increase the potential of surface runoff entering the subsurface aquifer and thereby contaminating the ground-water supply of the district"--Abstract, page iii.

Advisor(s)

Jay M. Gregg
Jeffrey D. Cawlfield

Committee Member(s)

Neil L. (Neil Lennart) Anderson, 1954-
Allen W. Hatheway
Charles W. Rovey II

Department(s)

Geosciences and Geological and Petroleum Engineering

Degree Name

Ph. D. in Geology and Geophysics

Comments

Eighteen (18) plates, folded in the back pocket of the manuscript, are provided here as supplemental files. Due to their large size, these files may take more time to download.

Publisher

University of Missouri--Rolla

Publication Date

Fall 1999

Pagination

xvi, 141 pages, maps

Note about bibliography

Includes bibliographical references (pages 132-139).

Rights

© 1999 Robert Weiser Dillon, All rights reserved.

Document Type

Dissertation - Open Access

File Type

text

Language

English

Thesis Number

T 7708

Print OCLC #

45427248

Recommended Citation

Dillon, Robert Weiser, "Stability of paleosinks and karstic carbonates in the Southern Fire Clay Mining District of Missouri" (1999). Doctoral Dissertations. 1334.
https://scholarsmine.mst.edu/doctoral_dissertations/1334