东非裂谷系东支是新生代形成的陆内裂谷盆地群，南洛基查盆地位于东支裂谷系肯尼亚地区北部，自2012年以来已相继发现8个油田，累计发现2C储量766 MMbbl。通过对南洛基查盆地地震、钻井等地质资料综合研究，厘清了其油气地质特征及成藏规律。作为小型箕状断陷湖盆，盆地具有西断东超构造特征，西侧陡坡带以形成构造—岩性复合圈闭为主，东侧缓坡带以断块构造圈闭为主。盆地沉积充填为河流—（扇）三角洲—湖泊沉积体系，呈现出初始裂陷期—扩张期—萎缩期旋回特征。盆地发育渐新统—下中新统和中—下中新统2套成藏组合。根据对南洛基查盆地已发现油气田的解剖，认为成熟烃源岩、有效储集层及成藏要素间的合理配置是东支裂谷系油气规模成藏的主控因素。结合重力、地震、沉积厚度等资料综合分析，认为凯里奥山谷盆地、图尔卡纳盆地西北陆上和凯里奥盆地同样具有良好勘探潜力，值得重点关注。%The eastern branch of the East African Rift System belongs to an intracontinental rift basin group formed during the Cenozoic. The South Lokichar Basin is located in the north of Kenya. Since 2012, 8 oil fields have been discovered here, with 2C resource being 766 million bbl. Through integrated study of seismic, well and other geological data, we investigated the petroleum geological features and developed reservoir⁃forming rules. The basin has small⁃scale, mono⁃faulted structural characteristics, faulting to the west and overlapping to the east. In the western steep⁃slope zone, there are mainly structural-lithologic combination traps, and in the eastern gentle slope zone is structural traps. Depositional fill is characterized by a river⁃( fan ) delta⁃lacustrine sedimentary system, presenting a cycle of initial rifting stage⁃expanding stage⁃waning stage. There are two sets of plays, one is Oligocene-Lower Miocene combination and the other one is Middle-Lower Miocene combination. Based on the analysis of discovered fields in the South Lokichar Basin, it was determined that mature source rocks, significant reservoirs and reasonable positioning of accumulation elements were the main controlling factors in the eastern branch rifts. The exploration potential of the eastern branch rift system was analyzed through com⁃prehensive interpretation of gravity, seismic and depositional thickness data. The most favorable targets deserving attention are the Kerio Valley Basin to the south of South Lokichar Basin, the northwest onshore of the Turkana Basin and the Kerio Basin.
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