Sinkhole risk in Mason County, KY: Sinkhole country

Sinkhole country

Soluble rock at or near the surface across much of the county.

On soluble rock: 76%
At or near the surface: 76%
Buried under cover: under 1%

What this means before you buy

Get a sinkhole or geotechnical inspection before buying, building or adding weight to a foundation.

That works out to roughly 182 of Mason County's 240 square miles on soluble rock, 181 of them with the rock at or near the surface. With about 16,956 residents (71 per square mile), homes are spread across towns and farmland, and a mapped unit may or may not reach the developed parts. The figures come from 588 map points about 0.6 miles apart, so a pocket smaller than that can be missed or overstated.

Counties around Mason County

The closest county with no soluble rock mapped is Scioto County, OH, about 47 miles east. 1 of the 6 closest counties land in the same band; the ground changes quickly around here.

Robertson County, KY 14 mi southwest · 39% at surface
Bracken County, KY 17 mi west · 33% at surface
Fleming County, KY 17 mi southeast · 58% at surface
Nicholas County, KY 21 mi southwest · 38% at surface
Brown County, OH 23 mi north · 9% at surface
Lewis County, KY 25 mi east · 22% at surface

Which formation it is

The largest mapped soluble unit here is the Ashlock Formation, Grant Lake and Calloway Creek Limestones, and Fairview Formation, undivided (limestone), Ordovician in age, covering about 53% of the county. Next is the Bull Fork Formation at 22%.

Against the rest of Kentucky

Mason County ranks 17 of 120 in Kentucky for soluble rock at the surface, and sits above 94% of US counties on that measure.