Sinkhole risk in Randall County, TX: 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: 3%
At or near the surface: 3%
Buried under cover: 0%

What to do about a house in Randall County

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

That works out to roughly 30 of Randall County's 913 square miles on soluble rock, 30 of them with the rock at or near the surface. With about 150,547 residents (165 per square mile), homes are spread across towns and farmland, and a mapped unit may or may not reach the developed parts. The figures come from 396 map points about 1.5 miles apart, so a pocket smaller than that can be missed or overstated.

Counties around Randall County

The nearest county rated sinkhole country is Briscoe County, TX, about 49 miles southeast. 1 of the 6 closest counties land in the same band; the ground changes quickly around here.

Potter County, TX 30 mi north · 11% at surface
Armstrong County, TX 31 mi east · 27% at surface
Swisher County, TX 31 mi south · 0% at surface
Castro County, TX 36 mi southwest · 0% at surface
Deaf Smith County, TX 40 mi west · under 1% at surface
Carson County, TX 43 mi northeast · under 1% at surface

What Randall County is built on

The largest mapped soluble unit here is the Dockum Group, undivided (fine-grained mixed clastic), Late Triassic in age, covering about 3% of the county. Next is the Quartermaster Formation at under 1%.

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 Texas

Randall County ranks 129 of 254 in Texas for soluble rock at the surface, and sits above 60% of US counties on that measure.