The Hyannis 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.
Hyannis’s center stands about 3,760 ft above sea level. Within three miles the land runs from 3,690 ft to 3,980 ft, a difference of 290 ft: rolling country. The highest named summit within 15 miles is Wild Horse Hill, about 4,180 ft, 10 miles west-southwest.
Under the town center the state geologic map shows Ogallala Group or Formation (siltstone-mudstone, conglomerate-sandstone), from the Miocene, 5.3 to 23 million years old.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 40×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Siltstone-mudstone, conglomerate-sandstone. Age: Miocene, 5.3 to 23 million years old. About 24 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.