The Gross 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
Mostly sunny; warmer
Mostly sunny
Partly cloudy
Partly cloudy
Partly cloudy; cooler
Showers likely
Gross’s center stands about 1,770 ft above sea level. Within three miles the land runs from 1,460 ft to 1,830 ft, a difference of 370 ft: rolling country.
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.
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 33×. 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: Late Cretaceous, 66 to 100 million years old. About 10 mi of the line.
Siltstone-mudstone, conglomerate-sandstone. Age: Miocene, 5.3 to 23 million years old. About 7 mi of the line.
Shale, bentonite. Age: Late Cretaceous, 66 to 100 million years old. About 5 mi of the line.
Shale. Age: Late Cretaceous, 66 to 100 million years old. About 1 mi of the line.
Chalk, marlstone, shale. Age: Late Cretaceous, 66 to 100 million years old. About 1.0 mi of the line.
Limestone, shale. Age: Late Cretaceous, 66 to 100 million years old. About 0.6 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 Gross reaches the Gulf of America by way of Whisky Creek, Ponca Creek, the Missouri and the Mississippi: about 2,040 river miles.
Lake on the way: Lewis and Clark Lake.
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 Gross; river miles along the main stem, rounded.
