The Forest River 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.
Forest River’s center stands about 860 ft above sea level. Within three miles the land runs from 830 ft to 890 ft, a difference of 60 ft: nearly flat ground.
Under the town center the state geologic map shows Mowry-Skull Creek, Undivided (shale, sandstone), from the Early Cretaceous to Late Cretaceous, 66 to 145 million years old.
The section below crosses 4 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 56×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Shale, sandstone. Age: Early Cretaceous to Late Cretaceous, 66 to 145 million years old. About 11 mi of the line.
Shale. Age: Late Cretaceous, 66 to 100 million years old. About 7 mi of the line.
Sandstone, shale. Age: Early Cretaceous, 100 to 145 million years old. About 6 mi of the line.
Shale. Age: Late Cretaceous, 66 to 100 million years old. About 1 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 Forest River reaches Hudson Bay by way of the Forest, the Red River of the North and the Nelson: about 920 river miles. Past the border it runs north through Canada to Hudson Bay.
Lake on the way: Lake Winnipeg.
400 miles of the trip are on the Nelson.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Forest River; river miles along the main stem, rounded.