The occurrence of fossil bearing material depends on environmental factors before and after the time of preservation. After death, the first preserving factor is a rapid burial in water bodies or terrestrial sediment which would help in preserving the specimen. These rocks types are usually termed clastic rock, and are further subdivided into fine, medium and coarse grained material. While fossil's can be found in all grain typed, more detailed specimens are found in the fine grained material. A second type of burial is the non-clastic rock, form where the rock is made up of the precipitation of compacted fossil material, types of rock include limestone and coal. The third fossil bearing material is the evaporates, which precipitate out of concentrated dissolved salts to form nodular deposits, examples include rock salt and phosphate concentrations. The evaporates are usually associated with gastropod, algae, vertebrate, and trace fossils.
After burial various factors are at work to endanger the current fossil's preserved state. Chemical alteration would change the mineral composition of the fossil, but generally not its appearance, lithification would distort its appearance, the fossil itself may be fully or partially dissolved leaving only a fossil mold.
Areas where sedimentary rocks are being eroded include exposed Mountainous areas, river banks and beds and engineering features like quarries and road cuts. Generally in appearance, a fossil will be either a different colour to the surrounding rock, because of the different mineral content, will have a defining shape and texture or a combination of both. Dried up natural lake beads and caves in the form of pitfall traps also has an occurrence of a recent fossil fauna for the locality as is the case with Cuddie Springs and Naracoorte Caves in Australia.