鄂尔多斯盆地下古生界奥陶系碳酸盐岩生烃能力研究

Study on Hydrocarbon-producing Potential of Carbonate Rocks in Ordovician of Lower Paleozoic in Odros Basin

产率比是有机质在某一成熟度下的气态烃类产物的产率与其最终气态烃产率的百分比 ,对相同类型有机质的不同阶段的产率比进行分析可建立该类型有机质的产率比与成熟度的关系。元素平衡法是指有机质及其生成物、残留物间存在的一种物质平衡关系。应用产率比法和元素平衡法对鄂尔多斯盆地下古生界奥陶系碳酸盐岩的生烃能力进行了讨论 ,指出下古生界奥陶系泥质碳酸盐岩具有一定的生烃能力 ,其气态烃最终产率可达 4 2 0～ 4 30m3 /T·有机碳 ,相当于Ⅱ型干酪根的生烃能力 ;纯碳酸盐岩的生烃能力相对较低 ,气态烃产率只有 12 0m3 /T·有机碳。

In a maturity, the proportion derived between the gaseous hydrocarbon productivity and the final productivity of gaseous hydrocarbon from organic matter is the ratio of productivity, the connection between the ratio of productivity and maturity can be established by means of analyzing productivity ratio of the same type organic matter in different stage. The balance of element is a balance among matter, which exits between organic matter and its product and residual product. This paper mainly discusses the hydrocarbon producing potential of carbonate rocks in Ordovician system of lower Paleozoic group in Odros basin by employing the method of ratio of productivity and element balance, and find that carbonate rock containing clay can produce some amount of hydrocarbon in Ordovician system of lower Paleozoic group and its final productivity of gaseous hydrocarbon can reach the ratio of 420～430 m 3/T·C ot , which corresponds with that of Ⅱ type kerogen. At the same time, the pure carbonate rock bear relative low hydrocarbon producing potential (only 120 m 3/T·C ot ).