What is carbonaceous film and what types of organisms typically form this kind of trace fossial

A carbonaceous film, commonly known as carbon film is an organism silhouette or simply an outline of a fossil. It is a kind of fossil that is seen in any rock when organic material is compacted and flattened, which leaves only a carbon residue or film. The soft tissues of organisms are mostly made of organic carbon compounds. Fossils only contain carbon sometimes. Usually, fossiles form when sediment inters a dead organism. The organism's remains are put through pressure and heat when sediment piles up. These circumstances push gases and liquids from the body. A remainder of a thin film of carbon is left, which forms a silhouette of the primary organism, called a carbon film. Plant fossils usually take place as a residue or film of carbon. The frail fossils of the Burgess Shale are comprised of carbon film forms. An example of carbon film fossils are graptolites.

answer; the nazca plate is converging with the south american plate