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Learning to tell Neoproterozoic time
1Botanical Museum, Harvard University, Cambridge, MA 02138, USA.
Precambrian Research
|September 7, 2001
Summary
Scientists improved the understanding of the Terminal Proterozoic Period using multidisciplinary research. This work provides a framework for correlating events like the Marinoan ice age and Ediacaran animal diversification.
Area of Science:
- Geosciences
- Paleontology
- Stratigraphy
Background:
- The Terminal Proterozoic Period (approx. 720-541 million years ago) is critical for understanding major Earth system changes.
- Establishing a precise timeline for this period has been challenging due to limited high-resolution data.
Purpose of the Study:
- To improve the correlation and calibration of events within the latest Proterozoic Era.
- To establish a robust temporal framework for analyzing tectonic, biogeochemical, climatic, and biological events.
- To provide a rational basis for selecting a Global Stratotype Section and Point (GSSP) for the period.
Main Methods:
- Multidisciplinary research involving scientists from numerous countries.
- Chemostratigraphy and biostratigraphy utilizing single-celled microfossils (acritarchs).
- Integration of high-resolution radiometric dating.
Main Results:
- Significant advancements in the framework for correlating and calibrating latest Proterozoic events.
- Defined the interval by key phenomena: Marinoan ice age, Ediacaran animal diversification, and the start of the Cambrian Period.
- Developed a temporal framework essential for evaluating terminal Proterozoic events.
Conclusions:
- The research provides a strong foundation for defining the beginning of the Cambrian Period with a GSSP.
- Potential exists for achieving similar stratigraphic resolution for the preceding Cryogenian Period.
- Future prospects include lower Neoproterozoic correlation and subdivision, though data are currently limited.
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