ABSTRACT

Economic micropaleontology contributes to the search for hydrocarbons in two equally important ways: it provides the petroleum geologist with correlations and age determinations, and it is instrumental in the delimitation of fossil environments of deposition. This latter function involves the study of paleoecology, which deals with the relationships between fossil taxa and/or assemblages and their environments. Paleoecological studies depend heavily upon a thorough knowledge of the ecology of living organisms, but the methods and terminologies used in each field are distinctly different. As erroneous paleoecological information may seriously influence the geological interpretation of an area, a thorough knowledge of correct procedures and methods in paleoecology is essential, while its limitations must also be fully realized. This paper briefly discusses and summarizes these procedures, and defines and explains a necessary set of pertinent ecological and paleoecological terms, some of which are introduced here for the first time. Attention is drawn to certain erroneous procedures and misinterpretations commonly encountered in applied paleoecological studies. These include the indiscriminate use of well cuttings, the evaluation of poor faunas, and the taxonomic misidentification of fossils.