The Ponderosa 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.
Ponderosa’s center stands about 7,240 ft above sea level. Within three miles the land runs from 5,790 ft to 8,900 ft, a difference of 3,110 ft: mountain country. The highest named summit within 15 miles is Angora Mountain, about 10,160 ft, 12 miles north-northeast.
Under the town center the state geologic map shows Mesozoic granitic rocks, unit 3 (Sierra Nevada, Death Valley area, Northern Mojave Desert and Transverse Ranges) (granodiorite), from the Permian to Tertiary, 2.6 to 260 million years old.
The section below crosses 2 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 3×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Granodiorite. Age: Permian to Tertiary, 2.6 to 260 million years old. About 19 mi of the line.
Schist, gneiss. Age: Paleoproterozoic to Cretaceous, 66 to 2,500 million years old. About 5 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 Ponderosa reaches the Tulare Lake basin by way of Peppermint Creek and the Kern: about 110 river miles. The Tulare Lake basin has no outlet to the sea: the water leaves only by evaporating or soaking into the ground.
Lake on the way: Isabella Lake.
70 miles of the trip are on the Kern.
A lake that comes back. The bed of Tulare Lake is farmland now; in very wet years it floods again.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Ponderosa; river miles along the main stem, rounded.