Sinkhole risk in Alcorn County, MS: Pockets of it

Pockets of it

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

On soluble rock: 41%
At or near the surface: 41%
Buried under cover: 0%

The next step for one property

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 165 of Alcorn County's 400 square miles on soluble rock, 165 of them with the rock at or near the surface. With about 34,228 residents (86 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 368 map points about 1.0 miles apart, so a pocket smaller than that can be missed or overstated.

Two things to read before deciding: the signs to look for and how an inspection works, and how these percentages are measured.

Counties around Alcorn County

The nearest county rated sinkhole country is Tippah County, MS, about 21 miles southwest, close enough that the same rock may run under the county line. 1 of the 6 closest counties land in the same band; the ground changes quickly around here.

Prentiss County, MS 19 mi south · 24% at surface
McNairy County, TN 20 mi north · 11% at surface
Tippah County, MS 21 mi southwest · 60% at surface
Tishomingo County, MS 22 mi southeast · 10% at surface
Hardin County, TN 31 mi northeast · 9% at surface
Hardeman County, TN 33 mi northwest · 5% at surface

What Alcorn County is built on

The largest mapped soluble unit here is the Demopolis chalk (carbonate), Upper Cretaceous in age, covering about 23% of the county. Next is the Ripley formation at 18%.

Against the rest of Mississippi

Alcorn County ranks 10 of 82 in Mississippi for soluble rock at the surface, and sits above 85% of US counties on that measure.