FYI: They "pillars" are columnar joints. These develop due to slow cooling of basalt. The fractures are produced as it accommodates contraction as it cools due to the internal crystal-structure of basalt. Although this all happened underground, it got exposed as everything around it eroded away.
FYI: They "pillars" are columnar joints. These develop due to slow cooling of basalt. The fractures are produced as it accommodates contraction as it cools due to the internal crystal-structure of basalt. Although this all happened underground, it got exposed as everything around it eroded away.