| Devonian marine source-reservoir-seal assemblage developed in central Guangxi, with superior original accumulation condition, the prospect of hydrocarbon exploration is good, it is one of the most potential petroliferous basins in south China. Based on predecessor's achievements, guided by the theory of tectonic, sedimentology, sequence stratigraphy and reservoir sedimentology, along the main line of basin evolution, depositional evolution, and reservoir evolution, based on study of backbone section, well and auxiliary section, combined with macro observation and indoor micro analysis, sedimentary system, sequence stratigraphy, sequence litho-paleogeographic and source-reservoir-seal assemblage of sequence framework were studied in this area.1)Sequence classification plan of different facies area, such as platform-basin, isolate platform, shoreland platform, of Devonian in central Guangxi were redefined, and were contracted in different facies area.2)Combined with local sedimentary setting, based on integrative analysis of outcrop, drilling core and logging, the Devonian in Central Guangxi can be divided into 4 sedimentary systems and 10 sedimentary facies, further into several subfacies and microfacies, characteristic of different facies were studied in detail, depositional model of shore, carbonate platform and shelf were built.3)Sequence stratigraphy of study area were studied carefully, characteristic and genesis of sequence boundary were analyzed, the Devonian in Central Guangxi can be divided into 2 super sequence and 18 third-level sequence, every third-level sequence and its system tracts character were discussed, sequence was contracted, sequence framework was built, the third-order sequence can be fully contracted in study area.4)Based on study of sedimentary system and sequence stratigraphy, according to drawing method of tectonic sequence litho-paleogeographic, taking tectonic sequence as compilation unit, 5 tectonic sequence litho-paleogeographic map were drew, which manifest sedimentary framework of different stage of Devonian in study area. It is been gone through the stage of inland depression basin in SS1 super sequence and the stage of passive continental margin rift basin in SS2 super sequence. In lowstand period of SS1 super sequence, in general terrigenous detritus of shore deposited in Central Guangxi, in transgression period of SS1 super sequence, the pattern of basin among platforms firstly appeared, in highstand period of SS1 super sequence, synsedimentary faulting was strong, the pattern of basin among platforms became more obvious. In transgression period of SS2 super sequence, the pattern of basin among platforms was typical in Central Guangxi, reef developed very well, in highstand period of SS2 super sequence, water became shallower, platform basin withered, and it showed the character of filling gap.5)Based on the research on sedimentary system, sequence and sequence litho-paleogeographic, the characteristic of source-reservoir-seal in sequence framework was analyzed. Source rock, reservoir and seal rock individually developed in transgression system tracts (TST), highstand system tracts(HST) and lowstand system tracts(LST) of super sequence or sequence. There could be 2 favorable source-reservoir-seal assemblages of Devonian in Central Guangxi, one of which takes mudstone and shale of TST shelf and platform of Yujiang or Tangding formation as its source rock, dolomite of HST restricted platform of middle-lower Devonian Najiao, Shanglun, Sipai formation as its reservoir, mudstone, shale and marlite of middle Devonian Donggangling and yingtang as its seal rock. Another assemblage takes black shale of TST platform of middle Devonian Luofu formation as its source rock, biohermal limestone and dolomitic limestone of HST platform edge and dolomite and grained limestone of basin among platforms of middle-upper Devonian as its reservoir, mudstone, shale and marlite of platform of upper Devonian Wuzhishang and Liujiang formation as its seal rock.
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