柴达木盆地石炭系沉积相及其与烃源岩的关系

在实地观测柴达木盆地石炭系野外露头剖面岩性和生物特征的基础上，详细研究了柴达木盆地石炭系的沉积相类型及特征，探讨了石炭纪不同阶段的沉积演化以及沉积相对烃源岩发育的控制作用。柴达木盆地石炭系主要发育陆表海，可划分为三大沉积相:滨岸相、碳酸盐岩台地相、浅海陆棚相；六个亚相:浅滩亚相、潮坪亚相、沼泽亚相、开阔台地亚相、局限台地亚相、内陆棚亚相。石炭纪沉积演化经历了早石炭世两次海侵和晚石炭世的持续海侵，沉积环境由滨海向浅海过渡，以海陆交互沉积环境为主，大面积的海进使得北部山前局部地区出现地层超覆现象。沉积相控制了烃源岩的分布:柴达木盆地东北缘石炭系的潮坪亚相、浅海陆棚亚相广泛发育泥岩、炭质泥岩及碳酸盐岩，可作为有利的生烃源岩；柴西南缘下石炭统的局限台地亚相是碳酸盐台地上局部相对闭塞的地带，由于水体相对较深，水动能较低，沉积物中有机质丰富，也是有利的生烃源岩发育区。 

Relationship Between Carboniferous Sedimentary Facies and Source Rock in Qaidam Basin

This paper researched sedimentary styles and characteristics and discussed about Carboniferous sedimenta-ry evolution of different stages as well as relationship between Carboniferous sedimentary facies and source rock. It is epicontinental sea in Carboniferous of Qaidam. Sedimentary environment can be divided into three sedimentary facies: shore facies, carbonate plateau facies, neritic marine basin facies and six subfacies: shallows subfacies, tidal flat sub-facies, swamp subfacies, open platform facies, restricted platform subfacies and inner shelf subfacies. There are two marine ingression in Early Carboniferous and everlasting transgression in Late Carboniferous. Sedimentary environment evolves from offshore to epeiric sea and mainly develops paralic sedimentary environment. The overlapping phenome-non arose in the north foreland because of wide area transgression. The distribution of source rock is controlled by sed-imentary facies: mudstone, carbargilite and carbonate are favourable source rocks, which develop in swamp subfacies or inner shelf subfacies of carboniferous in the northeast of Qaidam basin; restricted platform subfacies is also a fa-vourable source rock distributed area because of deeper water, smaller kinetic energy, abundant organic material, which develop in relatively restricted area of Lower Carboniferous in the southwestern margin of Qaidam basin.