The Eldorado 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.
Eldorado’s center stands about 1,450 ft above sea level. Within three miles the land runs from 1,400 ft to 1,510 ft, a difference of 110 ft: gently rolling country.
Under the town center the state geologic map shows Van Vacter Member of Blaine Formation (gypsum, dolostone, shale), from the Permian, 252 to 299 million 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.
Gypsum, dolostone, shale. Age: Permian, 252 to 299 million years old. About 12 mi of the line.
Shale, siltstone. Age: Permian, 252 to 299 million years old. About 4 mi of the line.
Coarse-detrital, fine-detrital. Age: Pleistocene, less than 2.6 million years old. About 3 mi of the line.
Sand. Age: Holocene, less than 12,000 years old. About 3 mi of the line.
Fine-detrital. Age: Holocene, less than 12,000 years old. About 2 mi of the line.
Gypsum, dolostone. Age: Permian, 252 to 299 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 Eldorado reaches the Gulf of America by way of Sandy Creek, the Red River, the Atchafalaya and the Lower Atchafalaya: about 1,150 river miles.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Eldorado; river miles along the main stem, rounded.