Heaving 3 : The partial or complete collapse of the walls of a hole resulting from internal pressures due primarily to swelling from water absorption or formation of gas pressures. See: Sloughing. (Bul 10C, Bul D11).
The Mudblogger (Oilfield, Energy and Related Photographs), Oil Field Glossary, TX, USA 2014. http://mudblogger.com/oilfield-glossary/, (Oil - Amer) {777}