In which process are original tissues of the organism can be preserved

Organisms and other potential fossils must be naturally buried quickly to avoid rapid decomposition, scavenging, and erosion. Mud, silt, ash and resin are some of the more common materials. Parts Except in rare cases, bones, shells, and exoskeletons are the only remains of organisms that survive decomposition long enough to be candidates for fossilization. However, rapid burials resulting in anaerobic conditions can preserve soft tissues.