Final answer:
Ancient organisms are deeply buried due to natural sedimentation and preservation conditions that protect them from decay. Swift burial and special environments such as bogs, ice, or amber help in preserving these remains as fossils over geological timescales.
Step-by-step explanation:
The remains of ancient organisms are buried deeply within the earth predominantly due to natural processes. Over time, organisms that die and are not immediately decomposed can be covered by sediments such as silt and sand. These sediments gradually accumulate, layer upon layer, deeply burying the remains. This can take place in various environments, including the ocean floor or on land where conditions favor the preservation of organic material.
During the formation of fossils, swift burial is essential to protect the remains from scavengers and decay. In some instances, bodies are preserved in bogs due to the low-oxygen environment which impedes decomposition, or can be encased in amber, ice, or tar, providing a shield against natural decaying processes. Fossilization requires specific conditions, such as a lack of oxygen and the presence of protection against physical and biological decay. Thus, ancient organisms that are fossilized today are typically found deep within the earth because of the extensive period over which sedimentation and geological processes have occurred.