While many lava tubes consist primarily of a single conduit, it is not uncommon to have areas where passages branch and rejoin. Braiding occurs most actively near the leading portions of lava flows, and occurs because accretion of cooling lava occurs faster than downcutting or erosion. Hence, braiding occurs more often on the lower-gradient areas of the tube, that is, where the surface that the lava is flowing over is less steep.
Unlike the case for limestone caves, braided mazes tend to reconnect rather than diverge into broad dendritic patterns.
AUTHOR: Dave Bunnell