The Boston 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.
Boston’s center stands about 460 ft above sea level. Within three miles the land runs from 430 ft to 710 ft, a difference of 280 ft: rolling country. The highest named summit within 15 miles is Rohan Knob, about 1,070 ft, 14 miles east-southeast.
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 36×. 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. Age: Devonian to Carboniferous, 324 to 422 million years old. About 6 mi of the line.
Black-shale. Age: Devonian to Carboniferous, 324 to 422 million years old. About 6 mi of the line.
Sand, silt. Age: Pleistocene to Holocene, less than 2.6 million years old. About 5 mi of the line.
Limestone. Age: Silurian, 422 to 445 million years old. About 3 mi of the line.
Limestone. Age: Carboniferous, 324 to 359 million years old. About 2 mi of the line.
Limestone. Age: Carboniferous, 324 to 359 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 Boston reaches the Gulf of America by way of the Rolling Fork, the Salt River, the Ohio and the Mississippi: about 1,350 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 Boston; river miles along the main stem, rounded.