The Saltillo 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.
Saltillo’s center stands about 780 ft above sea level. Within three miles the land runs from 690 ft to 860 ft, a difference of 170 ft: gently rolling country. The highest named summit within 15 miles is Smith Hill, about 1,000 ft, 8 miles south-southeast.
Under the town center the state geologic map shows Blue River Group (limestone), from the Carboniferous, 324 to 359 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 41×. 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: Carboniferous, 324 to 359 million years old. About 14 mi of the line.
Siltstone. Age: Carboniferous, 324 to 359 million years old. About 7 mi of the line.
Limestone. Age: Carboniferous, 324 to 359 million years old. About 2 mi of the line.
Sandstone. Age: Carboniferous, 324 to 359 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 Saltillo reaches the Gulf of America by way of Carters Creek, the Lost, the East Fork White, the White River, Big Bayou, the Wabash River Old Channel, the Old Channel Wabash, the Ohio and the Mississippi: about 1,340 river miles.
970 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Saltillo; river miles along the main stem, rounded.