This collaborative project will assemble a continuous Astronomical Time Scale (ATS) for the Mesozoic Era (65 to 251 million years ago) from orbitally forced paleoclimate cycles recorded in stratigraphic data. The results should improve estimates of rates and timings of a wide range of Earth system processes by at least an order of magnitude. Project activities will be coordinated with more than a dozen international partners and will utilize the expertise of the Cretaceous, Jurassic, and Triassic subcommissions of the International Commission on Stratigraphy. The grand "team" goal is to extend the ATS, now virtually complete for the Cenozoic Era (0 to 65 million years ago), to encompass the past 250 million years. The methods that underpin the Cenozoic ATS will be applied to the Mesozoic. Emphasis will be placed on the goodness of fit of stratigraphic signals to astronomical models, duplication of records from different regions, and high-resolution calibration to geomagnetic polarity signatures and integrated bio- and chemostratigraphy. To aid in the science, a universally accessible signal processing toolbox will be created to modernize and unite leading statistical time series techniques used in cyclostratigraphic research, as well as in many other geoscience fields. Numerical ages from the reconstructed ATS will be inter-calibrated with other dating techniques in conjunction with NSF's EARTHTIME Project. All data and tools will be documented and accessible through multiple NSF public database systems, including GEON, CHRONOS, PaleoStrat, PBDB, and others. This project fulfills an ongoing global community initiative to develop a continuous, astronomical-calibrated, International Geologic Time Scale for the past quarter billion years of Earth history.
