The sea-level change and its response to the Late Paleozoic sequence stratigraphy in North China

Abstract：Based on data from such disciplines as sedimentology, coal geology, sequence stratigraphy and paleontology, the authors studied the sequence statigraphy, the relative sea-level fluctuation and its response to sequence stratigraphy. The results show that there are eight sequence surfaces, which mainly include palaeostructural surface, palaeontologic gap surface, large-area peat-moor surface, low stand floor surface of continental sea, transpressional basin surface, large-area buried erosion surface, large-area exposed surface, and siliceous spongolite surface. According to the principle of sequence stratigraphy division, the authors recognized one basin filling sequence, three tectonic sequences (second-grade sequences) and seven third-grade sequences. Two stages of relative sea level can be found based on the sequence stratigraphy framework. The first stage is from sequence 1 to sequence 3, which is composed of a short-time transgression and a long-time regression. The second stage is from sequence 4 to sequence 7, which is a long-time regression. On such a basis, the authors hold that the sea-level change of North China in Late Paleozoic can be studied by the sea-level curved shape and its response to sequence stratigraphy. The first characteristic is periodicity and compounding, and the second characteristic is high frequency and event synchronization.