三江盆地绥滨坳陷“滴道组”与东荣组地层及沉积相研究

Study on Stratum and Sedimentary Facies of "Didao Formation " and Dongrong Formation in Suibin Depression of Sanjiang Basin

通过绥滨坳陷"滴道组"与东荣组岩性特征、地震反射特征和层序发育特征的对比分析,发现在岩性方面这两套地层下部均含有砂砾岩、砾岩,中部以细砂岩、粉砂岩为主,上部沉积岩中均有火山岩夹层,不同的是"滴道组"含煤,东荣组不含煤;地震剖面上东荣组振幅及连续性好于"滴道组";层序发育过程中均经历了两次海平面升降变化,在时间上具有可对比性。平面上,绥滨坳陷东北部为东荣组纯海相沉积,而西南部为"滴道组"(扇)三角洲沉积。因此,原"滴道组"应划归东荣组,认为"滴道组"为东荣组的异相沉积。据此进一步揭示其具有良好的生储盖组合。

cludes coal bed, but Dongrong Formation does not. In seismic profile the amplitude and continuity of Dongrong Formation are better than ＂Didao Formation＂. Both ＂Didao＂ and Dongrong Formation experience twice sea level changes in sequence development process and they have pertinence. It is marine sediments of Dongrong Formation in northeast of Suibin depression and in the southwest ＂Didao Formation＂ is fan delta lake sediments. So the author considers that ＂Didao Formation＂ should be included in Dongrong Formation , and it is heteropical deposits of Dongrong Formation and hereby indicates that Didao and Dongrong Formation have well source rock-reservoir-cap combination.