The Sedan 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.
Mostly sunny
Mostly sunny; warmer
Partly cloudy
Partly cloudy
Chance of showers
Partly cloudy
Showers likely
Sedan’s center stands about 1,350 ft above sea level. Within three miles the land runs from 1,290 ft to 1,350 ft, a difference of 60 ft: gently rolling country.
Under the town center the state geologic map shows Granitic orthogneiss and migmatite (orthogneiss, migmatite), from the Paleoarchean to Mesoarchean, 2.8 to 3.6 billion years old.
The section below crosses 6 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.
Orthogneiss. Age: Paleoarchean to Mesoarchean, 2.8 to 3.6 billion years old. About 15 mi of the line.
Orthogneiss, migmatite. Age: Paleoarchean to Mesoarchean, 2.8 to 3.6 billion years old. About 3 mi of the line.
Orthogneiss. Age: Paleoarchean to Mesoarchean, 2.8 to 3.6 billion years old. About 3 mi of the line.
Granodiorite, granite. Age: Paleoproterozoic, 1.6 to 1.8 billion years old. About 3 mi of the line.
Leucocratic-granitic. Age: Neoarchean, 2.5 to 2.8 billion years old. About 1 mi of the line.
Age: Paleoproterozoic, 1.8 to 2 billion years old. About 0.2 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 Sedan reaches the Gulf of America by way of the East Branch Chippewa, the Chippewa, the Minnesota and the Mississippi: about 2,190 river miles.
Lake on the way: Lake Pepin.
1,750 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Sedan; river miles along the main stem, rounded.
