Block Diagram of the Southern San Joaquin Valley

The headwaters of the Kern River lie high in the mountains of the Sierra Nevada. Shortly after the river flows westward out of Lake Isabella reservoir, the Kern crosses the Kern River Fault. The lessening of slope on the downthrown (west) side of the fault, causes the river to dump a large part of its sediment load and build up the Kern River alluvial fan (from Page and others, 1986).