Chemostratigraphy and Biostratigraphic Correlation: Exercises in Systematic Stratigraphy

Global changes in marine geochemistry, on scales between one thousand and one million years permit the detailed correlation of sedimentary sequences in different ocean basins. The condition is that the geochemical signals are at least approximately dated by biostratigraphy (and magnetostratigraphy, where applicable). Through mutual reenforcement of chemostratigraphy and biostratigraphy unusually high stratigraphic resolution can be obtained. The integration of chemostratigraphy and biostratigraphy opens new avenues for analyzing the record-producing system within the framework of systemic stratigraphy. This type of stratigraphy focuses on global change in sea level, climate, and general geologic setting. It attempts to identify the underlying causes of global stratigraphic signals by considering 1) changes in input of matter and energy ; 2) changes in spatial distribution of sediments ; and 3) temporary changes in the partitioning of materials between active geochemical reservoirs. Examples from Pleistocene and Neogene deep-sea records illustrate the concepts and tools of this type of analysis