GEOLOGY

Detailed explanation-1: -Permineralization, where minerals like silica fill the empty spaces of shells, is the most common form of fossilization. Molds form when shells or bones dissolve, leaving behind an empty depression; a cast is then formed when the depression is filled by sediment.

Detailed explanation-2: -Sometimes when an animal dies and its body decays, it can leave an imprint in the sediment. If this imprint fills in with minerals from sediment and groundwater, it can harden to form a fossil. This fossil is called a cast fossil. The fossilized imprint is called a mold fossil.

Detailed explanation-3: -We find molds where an animal or plant was buried in mud or soft soil and decayed away, leaving behind an impression of their bodies, leaves, or flowers. Casts are formed when these impressions are filled with other types of sediment that form rocks, which take the place of the animal or plant.

Detailed explanation-4: -Fossil molds and casts preserve a three-dimensional impression of remains buried in sediment. The mineralized impression of the organism left in the sediment is called a mold. The mineralized sediment that fills the mold recreates the shape of the remains. This is called a cast.

Detailed explanation-5: -Fossil Casts and Molds: When an organism’s remains are buried in sediment, the shape of the remains can be preserved as a mold. A cast is created when the mold is filled with a different material, such as sediment or minerals. Molds and casts can preserve the shape of an organism, but not the details of its structure.