摘要
西藏尼玛盆地发育以灰绿色泥岩、纸片状页岩、钙质页岩为代表的陆相地层,前人将其归属为上白垩统竞柱山组。然而,这套地层中存在大量始新世—渐新世的孢粉组合,同时赋存有相当数量的时代为渐新世—中新世的鱼化石。因此,尼玛盆地的陆相地层时代应为古近纪始新世—渐新世。在这套陆相地层中还发现了油苗和沥青,表明尼玛盆地不仅是一个古近系陆相盆地,同时也是一个含油气盆地。由于尼玛盆地陆相地层与伦坡拉盆地连片分布,两个盆地的烃源岩和储盖层发育层位、特点以及组合特征都非常相似,表明两个盆地的生成、发育和演化过程都可以视为一个整体。
Terrestrial strata, which are representative of grey green mudstone as well as sheet-like and calcareous shale, are developed in Tibetan Nyima Basin. The strata were defined as the Upper Cretaceous Jingzhushan Formation by previous scholars. However, there are not only a lot of sporo-pollen assemblages from Eocene to Oligocene but also much more ichthyolite from Oligocene to Miocene. So, the timing of terrestrial strata can be defined from Eocene to Oligocene in Paleogene. Oil seepage and bitumen can be found in them, representing this basin is either a Paleogene terrestrial basin or a hydrocarbon-bearing basin. Lunpola Basin is very close to Nyima Basin. Source rocks, reservoirs and cap rocks of two basins and their characteristics along with assemblage are very similar, which shows that both them can be deemed as a whole in terms of their generation, development and evolution. Moreover, a hydrocarbon exploration in Lunpola Basin implies that there is a certain exploration prospect for Nyima Basin although with a very low exploration degree.
出处
《天然气技术》
2009年第4期21-24,共4页
NATURAL GAS TECHNOLOGY
基金
2006年中国石化油气先导项目<西藏中石化探区油气勘探潜力研究与选区评价>部分成果的总结
关键词
陆相地层
孢粉组合
鱼化石
古近系(纪)
竞柱山组
尼玛盆地
terrestrial strata, sporo-pollen assemblage, ichthyolite, Paleogene, Jingzhushan Formation, Nyima Basin
