应用化学降解方法研究固体沥青——以川东北固体沥青为例

采用选择性化学降解方法并结合多种有机地球化学测定手段对川东北固体沥青的母质来源及成因进行了研究。与固体沥青中可溶有机质的对比结果表明,化学降解释放出的生物标志化合物具有相对低的热演化程度,可以反映早期的母质特征。生物标志化合物参数和沥青反射率数据表明此类固体沥青经历了相对较高的热演化作用,并可能遭受了一定的生物降解。由生物标志化合物推测该样品固体沥青的母源以菌藻类低等水生生物为主,且沉积在一个具有一定咸度或水体较深的环境。 

INVESTIGATION OF THE SOLID BITUMEN BY CHEMICAL DEGRADATION METHOD——A CASE STUDY OF THE SOLID BITUMEN FROM THE NORTHEASTERN SICHUAN BASIN

An investigation on the parent material and the genesis of the solid bitumen from the northeas-tern Sichuan Basin has been carried out by using the selective chemical degradation method combined with various organic geochemical analysis and measurement techniques.Compared with the soluble organic matter extracted from the solid bitumen sample,the biomarker obtained by the chemical degradation method has relatively lower thermal maturity,and can reflect the characteristics of the parent materials of the early evolution stage.The data of the biomarker parameters and the bitumen reflectivity indicate that the solid bitumen has experienced a relatively high thermal evolution,and possibly has under-gone a certain degree of biodegradation.Based on the biomarker distribution of the solid bitumen in the sample,it can be inferred that the precursor of the solid bitumen dominantly derives from the low-level aquatic biota such as the bacteria and the algae,which were deposited under a brackish or relatively deep water environment.