吐哈盆地侏罗纪煤系有机质成烃作用

HYDROCARBON GENERATION FROM JURASSIC COAL AND COALY ORGANIC MATTERS IN TURPAN-HAMI BASIN

吐哈盆地是典型的煤成油气盆地。其主要成烃贡献组分为基质镜质体。应用重液分离富集技术获得较高纯度的单显微组分，并采用核磁共振波谱（13CNMR）和热解气相色谱（Py－GC）对其生烃性进行评价。结果表明，显微组分生油能力大小顺序为孢子体、角质体、基质镜质体、木栓质体和丝质体，基质镜质体生油能力为孢子体的一半；进入生油高峰早晚顺序为基质镜质体、角质作、木栓质体、孢子体。在此基础上，结合显微组分荧光机理，并考虑显微组分在烃源岩中所占比例，建立了吐哈盆地煤及其显微组分生烃模式。通过煤相分析，指出下三角洲平原及其上发育的分流间湾沼泽是煤系烃源岩发育的有利场所，流水沼泽相是煤成烃最有利相带。依据化学键能分析，提出O、S等杂原子的存在是煤中有机显微组分早期成烃的先决条件，非烃在煤成烃演化进程中具有重要作用。

Turpan-Hand basin is a typical basin where oils from coal are formed. The desmocollinite is the main contributor to oil deriving from coal.Based on 13C NMR and Py-GC, the macerals' hydrocarbon generation potential is assesed, It shows that oil generation potential of maccerals, such as sporinite, cutinite, desmocollinite, suberinite and fusinite, is displayed successively from large to small, desmocollinite has a half of sporinite' oil yield potential; the order of oil generation peak occurrence in time is desmocollinite, cutinite, suberinite and sporinite in succession. On the basis of this, combined with macerals fluorescent mechanism and considering every maceral in the proportion of whole rock source, the hydrocarbon generation models of coal and macerals are proposed. By means of coal facies analysis, it is pointed out that swamps which developed in the lower delta plain and the upper interdistributary bay are favorable places for source rocks in coal measures;rurining water swamp facies is mostly agreeable to hydrocarbon derived from coal. According to chemical band energy, it is indicated that O, S atoms exited in coal is the prerequisite of hydrocarbon generation from coal in the early evolution stage;resins are of importance in the process of hydrocarbon evolution.