SinkholeOdds

Sinkhole risk in Norton 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
22%
At or near the surface
22%
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 196 of Norton County's 878 square miles on soluble rock, 196 of them with the rock at or near the surface. With about 5,335 residents (6 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 412 map points about 1.5 miles apart, so a pocket smaller than that can be missed or overstated.

Two things to read before deciding: why gypsum and salt move faster than limestone, and the signs to look for and how an inspection works.

Counties around Norton County

The nearest county rated sinkhole country is Harlan County, NE, about 38 miles northeast, close enough that the same rock may run under the county line. 5 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

What Norton County is built on

The largest mapped soluble unit here is the Ogallala Formation (arkose), Miocene in age, covering about 18% of the county. Next is the Niobrara Chalk at 4%.

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

Norton County ranks 54 of 105 in Kansas for soluble rock at the surface, and sits above 76% of US counties on that measure.