The quality of the fossil record: A sequence stratigraphic perspective

Abstract

As paleobiology continues to address an ever broader array of questions, it becomes increasingly important to interpret confidently the meaning of the pattern of fossil occurrences as found in outcrop. To this end, sequence stratigraphy is an important tool for paleobiologists because it predicts the distribution of unconformities, facies changes, and changes in sedimentation rate, all factors known from numerous previous studies to affect the quality of the fossil record. Computer simulations now make it possible not only to model sequence architecture within sedimentary basins, but also to model the occurrence of fossils within those basins. These models generate predictions regarding the stratigraphic distribution of first and last occurrences, changes in species abundance, changes in species morphology, and the distribution of gaps in fossil ranges. Although confirmation of some of these predictions has been found in field studies, the extent to which these predictions describe the fossil record in general is still unknown. If the predicted patterns of fossil occurrences are found to be widespread, it will suggest that a relatively simple model of fossil occurrences in outcrops could become a new tool for solving a wide array of paleobiologic and biostratigraphic problems. With such models, paleobiologists and biostratigraphers will be able to use model data to test the accuracy of newly developed methods of analysis.