The Roff 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.
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Showers likely; cooler
Chance of showers; warmer
Sunny
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Mostly cloudy
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Roff’s center stands about 1,250 ft above sea level. Within three miles the land runs from 1,150 ft to 1,320 ft, a difference of 170 ft: gently rolling country.
Under the town center the state geologic map shows Ada Group or Ada Formation (shale, sandstone, limestone), from the Carboniferous, 299 to 324 million years old.
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 39×. 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, sandstone, limestone. Age: Carboniferous, 299 to 324 million years old. About 7 mi of the line.
Limestone, shale. Age: Middle Ordovician to Late Ordovician, 445 to 471 million years old. About 3 mi of the line.
Shale, limestone, sandstone. Age: Carboniferous, 299 to 324 million years old. About 3 mi of the line.
Shale, sandstone, limestone. Age: Carboniferous, 299 to 324 million years old. About 2 mi of the line.
Marlstone, shale, limestone. Age: Silurian to Early Devonian, 394 to 445 million years old. About 2 mi of the line.
Fine-detrital. Age: Holocene, less than 12,000 years old. About 2 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 Roff reaches the Gulf of America by way of the Blue River, the Red River, the Atchafalaya and the Lower Atchafalaya: about 880 river miles.
610 miles of the trip are on the Red River.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Roff; river miles along the main stem, rounded.
