Reviews on sequence hierarchy and driving mechanism

Two kinds of classification schemes for sequence hierarchy have been proposed by the previous geologists. The one depends on physical attributes of boundary rather than cycle duration. This kind of classication schemes is much more convenient for the stratigraphic division of small isolated continental facies basins. The other is based on the cycle duration or boundary frequency, and emphasizes global sea-level changes as the main driving force behind stratigraphic cyclicity. This kind of classication schemes has provided an effective way to the study of global changes and large-scale stratigraphic correlation. It is a widely perceived notion that the sequences are the products of interaction among sea-level changes, tectonism and sediment supply. The integration of stratigraphic cyclicity and astronomic orbital cycles will offer some profound thoughts not only on the final driving mechanisms but also on possible future directions and problems. Many problems remain to be resolved for the Precambrian stratigraphic division and correlation due to the limit of the existing sequence stratigraphic models only based on the Phanerozoic data.