What process describes the change of limestone into marble?

The transformation of limestone into marble occurs under conditions of heat and pressure metamorphism. This process involves the recrystallization of the calcite present in limestone when subjected to elevated temperatures and pressures, which typically occur deep within the Earth's crust. As the limestone is subjected to these conditions, the original calcite crystals dissolve and reform into larger crystals, resulting in the denser and more durable marble.

Heat and pressure metamorphism is a fundamental concept in geology that explains how sedimentary rocks, like limestone, are altered into metamorphic rocks, such as marble, through significant geological processes. These processes can occur over long periods and involve complex reactions that alter the mineral structure and composition of the rock without the rock melting.

This understanding highlights the role of temperature and pressure in metamorphic processes, distinguishing it from other geochemical processes, such as chemical weathering, which involves the breakdown of rocks and minerals at or near the Earth's surface due to exposure to environmental factors, and biological alteration, which refers to the effects of biological organisms on rock and soil.