Cutbank
A cutbank is a concave section of a tube wall formed on the outside edge of a meandering passage. Much like a moving stream, a flow of lava will erode sections on the outside side edge of a meandering passage, where the erosive force is greatest because velocity and turbulence are higher here. Evidence is strong that the primary means of erosion is via melting, and not by mechanical erosion.
AUTHOR: Dave Bunnell