Abstract:

The level of achievable geological time precision, accuracy and resolution determines the nature of the deeptime ecological, climatic, biological evolution and basic geological questions for which a reasonable answer may be expected. The main dating and correlation techniques include radiometric isotopic geochronology, biostratigraphy, magnetostratigraphy and cyclostratigraphy, and each has its own advantage and disadvantage. There might have some inconsistencies between the dating results of different techniques. Earthtime is an organized, communitybased, extensive international cooperation project. Its scientific objectives are to integrate, calibrate and improve highprecision geochronology and quantitative chronostratigraphy, to develop the geochronological techniques necessary to produce geological time with uncertainties approaching to 01%, and finally to precisely determine the ages and sequences in the deep time of Earth history. The continuous terrestrial Cretaceous developed in the Songliao Basin, northestern China, provides a unique opportunity to carry out high resolution integrated geochronological research, and its accomplishment will be an important complement and contribution of the Earthtime project applied in the Mesozoic continental records.

Key words: Earthtime, Deep Time, dating precision, temporal resolution, Songliao Basin, Cretaceous