The Mojave River is the largest drainage system in the Mojave Desert. At its peak during this last ice age, the Mojave River drainage basin extended from the San Bernardino Mountains in the west; it flowed east and north ultimately merging with the Amargosa River before draining into Lake Manley in Death Valley. The Mojave River is unique as for most of its length water flows below ground, under the sand and instead of flowing toward the ocean as rivers do, the Mojave flows inland, terminating in the middle of the desert.
Geology of the Area
While geologic studies of Southern California are still under way, many researchers think that our faults have reshaped the land through block movement and formation of active cinder cone volcanoes in the Mojave Desert.
The crust of the Mojave is less dense than the surrounding rock, due to this characteristic the rock melts more easily and rises toward the surface. When magma can not reach the surface it pools into magma chambers. The chambers can be huge. providing enough magma for many volcanoes over several years. Only when the magma reaches the surface is a volcano made.
The spaces between faults are points of weakness. Pressure builds at these fracture points beneath the fault lines. Through vents in the crust magma finds its way to the surface as new lava.