Sinkhole risk in Marshall County, MN: 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: 13%
At or near the surface: 0%
Buried under cover: 13%

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 238 of Marshall County's 1,775 square miles on soluble rock. With about 8,771 residents (5 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 410 map points about 2.1 miles apart, so a pocket smaller than that can be missed or overstated.

Worth reading for this county: why the 13% under cover still counts, and how these percentages are measured.

Counties around Marshall County

The nearest county rated sinkhole country is Boyd County, NE, about 395 miles south. 3 of the 6 closest counties land in the same band; the ground changes quickly around here.

Pennington County, MN 25 mi southeast · 0% at surface
Kittson County, MN 34 mi northwest · 0% at surface
Red Lake County, MN 37 mi south · 0% at surface
Roseau County, MN 37 mi northeast · 0% at surface
Polk County, MN 41 mi south · 0% at surface
Grand Forks County, ND 59 mi southwest · 0% at surface

What Marshall County is built on

The largest mapped soluble unit here is the Middle and Upper Ordovician rocks, undivided (sandstone), Middle and Late Ordovician in age, covering about 13% of the county.

Against the rest of Minnesota

Marshall County ranks 49 of 87 in Minnesota for soluble rock at the surface, and sits above 0% of US counties on that measure.