Columnar basalt is a type of rock formation characterized by hexagonal columns that result from the cooling and contraction of basaltic lava. These columns typically form in parallel arrays and are often found in volcanic regions. Columnar basalt formations are significant in the study of volcanic processes and the cooling behavior of lava.
Source Goehring, L., Morris, S. W., & Lin, Y. (2006). “Granular-Fluid Behavior in Columnar Basalt Formation.” Physical Review Letters, 97(9), 095503.