The Challis 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.
Partly cloudy
Partly cloudy
Chance of showers
Showers likely
Chance of showers
Chance of showers
Chance of showers
Challis’s center stands about 5,220 ft above sea level. Within three miles the land runs from 4,890 ft to 6,670 ft, a difference of 1,780 ft: steep hill country. The highest named summit within 15 miles is White Mountain, about 10,370 ft, 14 miles west-northwest.
The section below crosses 7 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 4×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Dacite, andesite, rhyolite. Age: Eocene, 34 to 56 million years old. About 10 mi of the line.
Limestone, dolostone. Age: Cambrian to Ordovician, 445 to 542 million years old. About 5 mi of the line.
Age: Neoproterozoic to Cambrian, 487 to 1,000 million years old. About 3 mi of the line.
Gravel, sand, silt. Age: Quaternary, less than 2.6 million years old. About 3 mi of the line.
Gravel. Age: Quaternary, less than 2.6 million years old. About 1 mi of the line.
Dolostone, limestone, sandstone. Age: Ordovician to Devonian, 359 to 487 million years old. About 0.9 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale. 1 smaller unit 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 Challis reaches the Pacific Ocean by way of Garden Creek, the Salmon, the Snake and the Columbia: about 830 river miles.
Lake on the way: Lake Umatilla.
320 miles of the trip are on the Salmon.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Challis; river miles along the main stem, rounded.
