The Kilby Butte Colony 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.
Kilby Butte Colony’s center stands about 3,120 ft above sea level. Within three miles the land runs from 3,080 ft to 3,490 ft, a difference of 410 ft: hilly country. The highest named summit within 15 miles is Three Buttes, about 4,580 ft, 13 miles south-southeast.
The section below crosses 11 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 14×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Sandstone, shale. Age: Early Paleocene to Middle Paleocene, 59 to 66 million years old. About 15 mi of the line.
Shale, sandstone, bentonite. Age: Early Paleocene, 62 to 66 million years old. About 2 mi of the line.
Shale, dolostone, limestone. Age: Late Cretaceous, 87 to 90 million years old. About 2 mi of the line.
Sandstone. Age: Early Paleocene, 62 to 66 million years old. About 1 mi of the line.
Sandstone, sandstone-mudstone. Age: Late Cretaceous, 72 to 87 million years old. About 0.9 mi of the line.
Sandstone, shale. Age: Late Cretaceous, 72 to 84 million years old. About 0.7 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale. 5 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 Kilby Butte Colony reaches the Gulf of America by way of the Musselshell, the Missouri and the Mississippi: about 3,200 river miles.
Lakes on the way: Lake Oahe, Lake Sakakawea, Lake Fort Peck and Lake Sharpe.
1,170 miles of the trip are on the Mississippi.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Kilby Butte Colony; river miles along the main stem, rounded.