Sinkhole risk in Garfield County, OK: Mostly deep or small

Mostly deep or small

Some soluble rock, mostly deeply buried or in a small share of the county.

On soluble rock: 8%
At or near the surface: 8%
Buried under cover: 0%

What this means before you buy

Sinkholes are uncommon here; watch for new depressions after heavy rain or leaking pipes.

That works out to roughly 88 of Garfield County's 1,059 square miles on soluble rock, 88 of them with the rock at or near the surface. With about 62,007 residents (59 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 384 map points about 1.7 miles apart, so a pocket smaller than that can be missed or overstated.

Counties around Garfield County

The nearest county rated sinkhole country is Major County, OK, about 42 miles west. 2 of the 6 closest counties land in the same band; the ground changes quickly around here.

Grant County, OK 28 mi north · 3% at surface
Kingfisher County, OK 31 mi south · 15% at surface
Noble County, OK 31 mi east · 0% at surface
Logan County, OK 37 mi southeast · 0% at surface
Alfalfa County, OK 38 mi northwest · 11% at surface
Major County, OK 42 mi west · 39% at surface

Which formation it is

The largest mapped soluble unit here is the Salt Plains Formation (shale), Early Permian in age, covering about 8% of the county.

8% of the county sits on gypsum or salt, which dissolves in years rather than millennia. That share matters more than its size suggests.

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 Oklahoma

Garfield County ranks 50 of 77 in Oklahoma for soluble rock at the surface, and sits above 66% of US counties on that measure.