The Logansport 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.
Logansport’s center stands about 220 ft above sea level. Within three miles the land runs from 170 ft to 300 ft, a difference of 130 ft: gently rolling country. The highest named summit within 15 miles is Bone Hill, about 400 ft, 12 miles southwest.
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 62×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Mudstone. Age: Late Paleocene to Early Eocene, 48 to 59 million years old. About 6 mi of the line.
Sand, clay, lignite. Age: Paleocene, 56 to 66 million years old. About 5 mi of the line.
Clay, silt, sand. Age: Pleistocene, less than 2.6 million years old. About 4 mi of the line.
Fine-detrital, coarse-detrital. Age: Holocene, less than 12,000 years old. About 2 mi of the line.
Sand. Age: Pleistocene to Holocene, less than 2.6 million years old. About 0.7 mi of the line.
Clay. Age: Holocene, less than 12,000 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.
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 Logansport reaches the Gulf of America by way of the Sabine: about 240 river miles.
Lakes on the way: Toledo Bend Reservoir and Sabine Lake.
140 miles of the trip are on the Sabine.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Logansport; river miles along the main stem, rounded.