The Big Woods 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.
Big Woods’s center stands about 800 ft above sea level. Within three miles the land runs from 780 ft to 830 ft, a difference of 50 ft: nearly flat ground.
Under the town center the state geologic map shows Hallock Red Beds (shale, limestone, dolostone), from the Jurassic, 145 to 202 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 64×. 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, dolostone. Age: Late Ordovician, 445 to 459 million years old. About 14 mi of the line.
Shale. Age: Jurassic, 145 to 202 million years old. About 5 mi of the line.
Shale, limestone, dolostone. Age: Jurassic, 145 to 202 million years old. About 4 mi of the line.
Sandstone, shale. Age: Early Cretaceous, 100 to 145 million years old. About 2 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 Big Woods reaches Hudson Bay by way of the Red River of the North and the Nelson: about 890 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 Big Woods; river miles along the main stem, rounded.