Out in the volcanic cinder cones, a few miles east of Baker in the Mojave National Preserve, and hidden among fields of broken basalt and cinder, is the Mojave Lava Tube. Over the course of the last seven million years (during the Pleistocene and Pliocene epochs) and perhaps as recently as 10,000 years ago, basalt lava flowed in multiple eruptive events from cinder cones here.
As the lava poured out of the vents, the crust on the flow hardened, while some parts remained liquid inside. When the eruption came to a stop, the stream of lava feeding a more distant part of the flow also stopped. This enclosed stream emptied out and formed a lava tube. Some tubes can be miles long, and others, like this one, only a hundred feet or so. They also can be great fun to explore. Geologists think this one was created during the first magma eruption of the cinder cone just off to the east. All of this volcanic activity would have been quite a sight to behold. The Park Service has some great info on all of this.
