Sinkhole risk in Osage County, OK: Pockets of it

Pockets of it

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

On soluble rock: 39%
At or near the surface: 39%
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 881 of Osage County's 2,247 square miles on soluble rock, 881 of them with the rock at or near the surface. With about 46,495 residents (21 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 283 map points about 2.8 miles apart, so a pocket smaller than that can be missed or overstated.

Counties around Osage County

The nearest county rated sinkhole country is Montgomery County, KS, about 54 miles northeast. 4 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

Pawnee County, OK 27 mi southwest · 31% at surface
Washington County, OK 28 mi east · 9% at surface
Chautauqua County, KS 38 mi north · 38% at surface
Kay County, OK 43 mi west · 26% at surface
Tulsa County, OK 43 mi southeast · 9% at surface
Nowata County, OK 45 mi east · 34% at surface

What Osage County is built on

The largest mapped soluble unit here is the Vanoss Group (shale), Late Pennsylvanian in age, covering about 15% of the county. Next is the Ada Group or Ada Formation at 12%.

Against the rest of Oklahoma

Osage County ranks 18 of 77 in Oklahoma for soluble rock at the surface, and sits above 84% of US counties on that measure.