CO2 emission accompanying the fracture of calcite

Abstract

Time resolved mass spectroscopy of the emissions accompanying the fracture of calcite (rhombohedral CaCO3) show that the principle volatile product, CO2, is released in bursts milliseconds after the fracture event. Similar measurements during the abrasion of calcite and during low temperature thermal decomposition of pulverized calcite show similar CO2 bursts. We argue that the observed bursts reflect localized decomposition of the calcite during the relaxation of reversible plastic deformation created by fracture and abrasion. This implies that mechanical, non-thermal processes play an important role in producing the observed decomposition products.