Sinkhole risk in Sheridan County, KS: Pockets of it

Pockets of it

Soluble rock at the surface or under thin cover in part of the county.

On soluble rock: 15%
At or near the surface: 15%
Buried under cover: 0%

What this means before you buy

Check the parcel against your state survey sinkhole map, and ask for an inspection if cracks, depressions or sticking doors show up.

That works out to roughly 134 of Sheridan County's 896 square miles on soluble rock, 134 of them with the rock at or near the surface. With about 2,397 residents (3 per square mile), much of the land is open, and the mapped rock may sit far from where people actually live. The figures come from 414 map points about 1.5 miles apart, so a pocket smaller than that can be missed or overstated.

Counties around Sheridan County

The nearest county rated sinkhole country is Harlan County, NE, about 79 miles northeast. 5 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

Decatur County, KS 30 mi north · 19% at surface
Graham County, KS 30 mi east · 33% at surface
Gove County, KS 30 mi south · 23% at surface
Thomas County, KS 34 mi west · 8% at surface
Norton County, KS 42 mi northeast · 22% at surface
Trego County, KS 43 mi southeast · 57% at surface

Which formation it is

The largest mapped soluble unit here is the Ogallala Formation (arkose), Miocene in age, covering about 15% of the county.

The county also lies over the Permian Basin, Anadarko Basin,Dalhart Basin, Palo Duro Basin, a deep salt or gypsum basin. Deep beds rarely cause surface collapse on their own, but wells and mining into them have.

Against the rest of Kansas

Sheridan County ranks 68 of 105 in Kansas for soluble rock at the surface, and sits above 71% of US counties on that measure.