The Gilliam 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.
Mostly sunny
Partly cloudy; warmer
Sunny
Sunny
Partly cloudy
Partly cloudy
Partly cloudy
0° on Nov. 17, 1959, the coldest reading for this week of the year since 1893. Next is 5° in 1932.
Gilliam’s center stands about 820 ft above sea level. Within three miles the land runs from 640 ft to 850 ft, a difference of 210 ft: rolling country.
Under the town center the state geologic map shows Riverton Formation, Burgner Formation (shale, siltstone, mudstone), from the Carboniferous, 299 to 324 million years old.
The section below crosses 5 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 64×. 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, mudstone. Age: Carboniferous, 299 to 324 million years old. About 11 mi of the line.
Clay, silt, sand. Age: Holocene, less than 12,000 years old. About 5 mi of the line.
Limestone. Age: Carboniferous, 324 to 359 million years old. About 4 mi of the line.
Limestone, shale. Age: Carboniferous, 299 to 324 million years old. About 3 mi of the line.
Shale, sandstone, siltstone. Age: Carboniferous, 299 to 324 million years old. About 1.0 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 Gilliam reaches the Gulf of America by way of Fish Creek, the Missouri and the Mississippi: about 1,390 river miles.
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 Gilliam; river miles along the main stem, rounded.
Gilliam has a hot-summer humid continental climate. Summer afternoons average 88° in July; winter nights fall to about 19° in January. A normal year brings about 8 inches of snow; with the rain, that comes to about 42 inches of water.
On November 14 Gilliam normally reaches 54° and falls to 34°. The record high is 80°, in 1964; the record low 6°, in 1940. The most rain on this date, 1.33 in, fell in 1985.
Normals 1991–2020 and records since 1893 at Marshall, 14 miles west-southwest. NOAA, through RCC-ACIS.
