In the oceans, the evolution of organisms with shells and mineralized skeletons generated thick layered deposits of minerals such as calcite, which would be rare on a lifeless planet.

• 在海洋中，生物的壳和成矿骨骼的进化产生了厚层的沉积，例如方解石。方解石在没有生命的行星是很难见到的！