1) Action 2) Activity 3) Fossilization 4) Natural action 5) Natural process 1) Fossilization 2) Petrifaction 3) Petrification 
fossilization, fossilisation (UK) 1. The process of fossilizing a plant or animal that existed in some earlier age. 2. The process of being turned to stone. 3. Becoming inflexible or out of date. Fossilization is considered a rare occurrence because most components of formerly-living things tend to decompose relatively quickly following death. ...