In recent years, with the deepening of oil and gas exploration, the reservoirs of Changxing-Feixianguan Formations reef shoal are gradually valued and become the main exploration layer after the medium-large gas fields such as Tieshanpo, Dukouhe, Puguang, Longgang and Yuanba were found in the northeast of Sichuan Basin. Therefore, this paper studies the characteristics of reservoir-forming assemblages of Changxing-Feixianguan Formations as the core, and finally predicts the favorable exploration plays in the northeast of Sichuan Basin. In view of the research purposes, this paper starts from sedimentary facies in the Changxing-Feixianguan period and combines with petroleum systems and accumulation events, and analyzes the characteristics of typical oil and gas reservoirs, and finally studies characteristics of oil-gas reservoir-forming assemblages in the northeast of Sichuan Basin. Controlled by the evolution of Kaijiang-Liangping trough, study area is mainly open platform-evaporation platform and shelf environment in Changxing-Feixianguan period. The Changxing-Feixianguan Formations develops reef pore-cracks limestone reservoirs, dolomite reservoirs, platform edge（inner）shoal pore-cracks dolomite reservoirs, intraplatform shoal pore dolomite reservoirs. Based on the Lower Silurian source rocks and the Middle-Upper Permian source rocks, the study area is mainly develops S1-P3ch petroleum system and P2.P3-P3ch.T1f petroleum system. Through the analysis of the typical gas reservoirs in the northeast of Sichuan Basin, the Changxing-Feixianguan Formations oil and gas reservoirs are divided into S1.P2.P3 sources-P3ch reservoir short distance vertical migration model（Yuanba model）and S1.P2.P3 sources-P3ch.T1f reservoirs vertical migration model（Longgang-Puguang model）. Based on the reservoirs of Changxing-Feixianguan Formations, three types of reservoir-forming assemblages were established, they are reef limestone reservoir-forming assemblage, intraplatform shoal dolomite reservoir-forming assemblage and the shallows dolomite reservoir-forming assemblage. Based on the study of hydrocarbon accumulation conditions and its relationship in time and space, the South Daba Mountain front thrust belt, the Dazhou-Kaijiang-Liangping area in the thrust belt of eastern Sichuan Basin and the Longgang area in Langzhong-Pingchang slope are favorable exploration plays for Changxing-Feixianguan Formations reef?shoal reservoirs. The southwest of Tongnanba anticline, the middle south of Jiulongshan anticline and the middle broken fold belt are less favorable exploration plays.
Wu Shunli He Dengfa. Characteristics of oil and gas reservoir formation and favorable exploration zone of Changxing-Feixianguan Formations, in the northeast of Sichuan Basin[J]. Chinese Journal of Geology, 2018, 53(1): 242-268.