Answer to Question 1It is relatively easy to distinguish between marine and terrestrial organisms, based on a comparison
with their living counterparts. Strong invertebrate shells usually indicate a high-energy environment,
such as the intertidal zone; deep-sea fossils are microscopic and fragile. Marine microfossils are
particularly important because so many can be retrieved in a single core sample. Coral reef deposits
are bounded in depth, as well as latitude, and are always marine.
Answer to Question 2The types of coal include bituminous, lignite, subbituminous, and anthracite. Anthracite is the best
because it burns more cleanly and efficiently than the other types.