Martian lava tube Martian lava tube Martian lava tubes are natural sub-surface lava tube caverns on Mars that are believed to form as a result of fast-moving, basaltic lava flows associated with shield volcanism. Lava tubes usually form when the external surface of the lava channels cools more quickly and forms a hardened crust over subsurface lava flows. The flow eventually ceases and drains out of the tube, leaving a conduit-shaped void space which is usually several meters below the surface. Lava tubes are typically associated with extremely fluid pahoehoe lava. Gravity on mars is about 38% that of Earth's, allowing Martian lava
Little Lava Lake side of Little Lava Lake and leads south into Three Sisters Wilderness and on to Williamson Mountain. Little Lava Lake Little Lava Lake lies in the Cascade Range about west-southwest of Bend in the U.S. state of Oregon. A close neighbor of Lava Lake, from which it is separated by solidified lava, Little Lava Lake is at an elevation of in the Deschutes National Forest. Generally considered the source of the Deschutes River, the lake covers to an average depth of . Lava Lake, Little Lava Lake, and other nearby lakes formed after lava flows from Mount Bachelor altered drainage