Sinkhole risk in Clearfield County, PA: No soluble rock mapped

No soluble rock mapped

No soluble bedrock mapped.

On soluble rock: under 1%
At or near the surface: under 1%
Buried under cover: 0%

What this means before you buy

No soluble bedrock is mapped here, so natural sinkholes are unlikely. Collapses from broken pipes or old mines are a separate risk.

That works out to roughly 10 of Clearfield County's 1,145 square miles on soluble rock, 10 of them with the rock at or near the surface. With about 78,132 residents (68 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 317 map points about 1.9 miles apart, so a pocket smaller than that can be missed or overstated.

Counties around Clearfield County

The nearest county rated sinkhole country is Union County, PA, about 74 miles east. 2 of the 6 closest counties land in the same band; the ground changes quickly around here.

Jefferson County, PA 29 mi west · 24% at surface
Elk County, PA 30 mi north · 0% at surface
Cameron County, PA 33 mi northeast · 0% at surface
Centre County, PA 34 mi east · 40% at surface
Blair County, PA 36 mi south · 36% at surface
Cambria County, PA 36 mi south · 2% at surface

Which formation it is

The largest mapped soluble unit here is the Mauch Chunk Formation (shale), Mississippian in age, covering about under 1% of the county. Next is the Allegheny Formation at under 1%.

The county also lies over the Michigan Basin; Ohio Basin; Appalachian 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 Pennsylvania

Clearfield County ranks 45 of 67 in Pennsylvania for soluble rock at the surface, and sits above 55% of US counties on that measure.