The Brandywine 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.
Brandywine’s center stands about 1,740 ft above sea level. Within three miles the land runs from 1,530 ft to 3,190 ft, a difference of 1,660 ft: steep hill country. The highest named summit within 15 miles is Kile Knob, about 4,570 ft, 13 miles west.
The section below crosses 13 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 7×. 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, siltstone. Age: Devonian, 359 to 422 million years old. About 4 mi of the line.
Siltstone, sandstone. Age: Devonian, 359 to 422 million years old. About 4 mi of the line.
Shale. Age: Devonian, 359 to 422 million years old. About 4 mi of the line.
Sandstone, shale. Age: Silurian, 422 to 445 million years old. About 3 mi of the line.
Shale, sandstone. Age: Devonian, 359 to 422 million years old. About 2 mi of the line.
Limestone. Age: Devonian, 359 to 422 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. 7 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 Brandywine reaches Chesapeake Bay and the Atlantic Ocean by way of the South Fork South Branch Potomac, the South Branch Potomac and the Potomac: about 390 river miles.
290 miles of the trip are on the Potomac.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Brandywine; river miles along the main stem, rounded.