The Delaware 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.
Delaware’s center stands about 720 ft above sea level. Within three miles the land runs from 660 ft to 760 ft, a difference of 100 ft: gently rolling country. The highest named summit within 15 miles is Blue Mound, about 1,000 ft, 10 miles west-northwest.
Under the town center the state geologic map shows Lenapah Formation (limestone, shale), from the Carboniferous, 299 to 324 million years old.
The section below crosses 8 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 63×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Shale, sandstone, limestone. Age: Carboniferous, 299 to 324 million years old. About 6 mi of the line.
Limestone, shale. Age: Carboniferous, 299 to 324 million years old. About 5 mi of the line.
Shale, sandstone, conglomerate. Age: Carboniferous, 299 to 324 million years old. About 3 mi of the line.
Limestone, shale. Age: Carboniferous, 299 to 324 million years old. About 2 mi of the line.
Shale. Age: Carboniferous, 299 to 324 million years old. About 2 mi of the line.
Sandstone, shale. Age: Carboniferous, 299 to 324 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. 2 smaller units along the line are not listed.
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 Delaware reaches the Gulf of America by way of California Creek, the Verdigris, the Arkansas and the Mississippi: about 1,120 river miles.
Lakes on the way: Oologah Lake, Murray Lake and Ozark Lake.
600 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Delaware; river miles along the main stem, rounded.