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Correlative study of the Ordovician chitinozoan biostratigraphy in China with grap- tolite and conodont biozones, and comprehensive analysis of the sequence- and event-strati- graphic indicated that 17 chitinozoan zones and 5 main chitinozoan diversification events subsequently occurring could be recognized in the Ordovician System of China. The 5 events comprise: event 1 — appearance of the earliest Ordovician chitinozoans, event 2 —appearance of C. symmetrica, event 3 —juvenile radiation of chitinozoans, event 4 —appearance of chitinozoans with high diversity, and event 5 —development of chitinozoans of deep-water facies. The age and feature of each event and its relation with the sea-level change and other geological event are discussed.
Correlative study of the Ordovician chitinozoan biostratigraphy in China with grap- tolite and conodont biozones, and comprehensive analysis of the sequence- and event-strati- graphic indicated that 17 chitinozoan zones and 5 main chitinozoan diversification events accidentally could be recognized in the Ordovician System of China. The 5 events comprise: event 1 - appearance of the earliest Ordovician chitinozoans, event 2 -appearance of C. symmetrica, event 3 -juvenile radiation of chitinozoans, event 4 -appearance of chitinozoans with high diversity, and event 5 -development of chitinozoans of deep-water facies. The age and feature of each event and its relation with the sea-level change and other geological events are discussed.