Mesozoic sequence framework of eastern Yihezhuang salient, Jiyang depression, Bohai Bay basin, China

摘要

The Mesozoic sequence framework of the eastern Yihezhuang salient in Jiyang depression, which was a residual basin, was studied in order to improve the success rate of locating hydrocarbon reservoirs. First, through seismic profiles, well logs and cores, complemented with outcrops, totally 5 sequence boundaries in Mesozoic were recognized, which included Tg, Tmz3, Tmz2, Tgm and Tr. Based on the recognized sequence boundaries, the Mesozoic sequence framework of eastern Yihezhuang salient got established. The entire Mesozoic succession was interpreted as two first-order sequences. One first-order sequence consisted of Early and Middle Jurassic and Late Jurassic, composed of three third-order sequences, which included SQ-Fz_1, SQ-Fz_2 and SQ-St from bottom to top. Respectively, the other first-order sequence consisted of Late Jurassic, composed of only one third-order sequence as truncated by late tectonic movement.