Analysis of high-resolution sequence stratigraphy and sedimentary microfacies of Guantao formation in Chenjiazhuang area

In order to clarify the sedimentary microfacies characteristics and gas-bearing interval of Guantao formation in Chenjiazhuang area, short-term cycles were identified by core observation data, and the template between lithology and electrical property was established. According to the logging curve response of short-term cycles, by intermediate-term cycles identification and transverse contrast, a high-resolution sequence stratigraphic framework was obtained with well logging data. The results show that Guantao formation can be divided into four intermediate-term cycles and sixteen short-term cycles, and the overlying cycle mainly contains retrogradation and accretion. Based on the stratigraphic framework, sedimentary facies variation with time and plane distribution in different subsequences were figured out. The region went through three stages of sedimentary facies evolvement, that is, alluvial-braided river sedimentary, braided river extensive development and evolvement from braided river to meandering river system?