The Sullivan 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.
Sullivan’s center stands about 970 ft above sea level. Within three miles the land runs from 700 ft to 1,030 ft, a difference of 330 ft: rolling country.
Under the town center the state geologic map shows Roubidoux Formation (sandstone, chert), from the Early Ordovician, 471 to 487 million years old.
The section below crosses 5 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 40×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Sandstone, chert. Age: Early Ordovician, 471 to 487 million years old. About 8 mi of the line.
Dolostone. Age: Early Ordovician, 471 to 487 million years old. About 7 mi of the line.
Shale, limestone, sandstone. Age: Carboniferous, 299 to 324 million years old. About 5 mi of the line.
Dolostone. Age: Early Ordovician, 471 to 487 million years old. About 3 mi of the line.
Dolostone. Age: Cambrian, 487 to 497 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 Sullivan reaches the Gulf of America by way of Winsel Creek, Spring Creek, the Bourbeuse, the Meramec and the Mississippi: about 1,270 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Sullivan; river miles along the main stem, rounded.