Sinkhole risk in Lincoln 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: 33%
At or near the surface: 33%
Buried under cover: 0%

What to do about a house in Lincoln County

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 236 of Lincoln County's 719 square miles on soluble rock, 236 of them with the rock at or near the surface. With about 2,928 residents (4 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 400 map points about 1.3 miles apart, so a pocket smaller than that can be missed or overstated.

Worth reading for this county: why gypsum and salt move faster than limestone, and the signs to look for and how an inspection works.

Counties around Lincoln County

The nearest county rated sinkhole country is Dickinson County, KS, about 58 miles east. 5 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

Mitchell County, KS 24 mi north · 38% at surface
Ellsworth County, KS 24 mi south · 19% at surface
Ottawa County, KS 31 mi east · 4% at surface
Russell County, KS 31 mi west · 47% at surface
Saline County, KS 35 mi southeast · 15% at surface
Osborne County, KS 36 mi northwest · 39% at surface

Which formation it is

The largest mapped soluble unit here is the Greenhorn Limestone and Graneros Shale (limestone), Late Cretaceous in age, covering about 31% of the county. Next is the Carlile Shale at 2%.

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

Lincoln County ranks 45 of 105 in Kansas for soluble rock at the surface, and sits above 81% of US counties on that measure.