So, how do organisms form carbon films?
Carbon is the main component of any organism or body.
Sediment can cover an organism after it dies.
All the materials in the body of the deceased organism eventually become unusable due to heat and the immense weight of the sediment layers.
After the more volatile oxygen, hydrogen, and nitrogen have disappeared, the body’s stable carbon remains.
The remaining carbon is in a thin layer or as a residue. It forms the body’s outline.
Fossils form when sediment buries an organism. When sediment accumulates, the remains of an organism are exposed to heat and pressure. These conditions cause liquids and gases to be forced out of the body. A thin layer of carbon residue remains, creating a silhouette of original organism known as a carbon film.