The North Allis plate. Relief from Copernicus GLO-30; rivers and lakes from USGS NHD; watersheds from the USGS Watershed Boundary Dataset; roads and city limits from Census TIGER 2024.
North Allis’s center stands about 780 ft above sea level. Within three miles the land runs from 600 ft to 870 ft, a difference of 270 ft: rolling country. The highest named summit within 15 miles is Black Mountain, about 960 ft, 7 miles north-northwest.
Under the town center the state geologic map shows Traverse Group (limestone), from the Middle Devonian, 384 to 394 million years old.
The section below crosses 3 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 54×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Limestone. Age: Middle Devonian, 384 to 394 million years old. About 13 mi of the line.
Dolostone. Age: Middle Devonian, 384 to 394 million years old. About 8 mi of the line.
Limestone. Age: Middle Devonian, 384 to 394 million years old. About 3 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale.
Heights from Copernicus GLO-90 (a surface model: it includes buildings and tree canopy); summits from USGS GNIS; rivers from USGS NHDPlus HR; rock from the USGS State Geologic Map Compilation.
A raindrop that lands in North Allis reaches Lake Huron by way of the Rainy, the Black River and the Cheboygan: about 25 river miles. From there it moves on through the Great Lakes, over Niagara Falls and down the St. Lawrence to the Atlantic.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of North Allis; river miles along the main stem, rounded.