开放体系下页岩生烃组分动力学研究：以渤南洼陷为例

A study on the compositional kinetics of shale hydrocarbon generation under an open system:Taking the Bonan sub-sag as an example

页岩生烃组分及气油比演化特征对页岩油资源评价及可动性研究具有重要意义。本文利用单冷阱热解气相色谱仪,结合Kinetics生烃动力学专用软件,对渤南洼陷沙三下亚段低熟泥页岩进行了开放体系条件下生烃组分动力学模拟,对该区页岩不同演化阶段生烃产物进行了分析,计算了干气(C_1)、湿气(C_2~C_4)、轻质烃(C_5~C_(14))及重质烃(C_(15+))组分动力学参数活化能E_i和频率因子A,并将页岩动力学参数进行地质过程外推应用,结合渤南洼陷埋藏史与热史,对该区页岩油生烃史,气油比等生烃特征进行了计算及研究。

The evolution characteristics of hydrocarbon composition and gas/oil ratio have an important significance for evaluating the resource and mobility of shale oil. In this study, based on the single cold trap pyrolysis chromatography analysis and the software Kinetics 2005, the kinetic simulation of hydrocarbon generation was carried out on the EESax shale from the Bonan sub-sag under the conditions of an open system. Pyrolysis products of shales at different evolution stages were analyzed to calculate the activation energy and frequency factor （.4） of dry gas （C1）, wet gas （C2-C4）, light oil （C5-C14） and heavy oil （C15＋） generation. Hydrocarbon generation history and hydrocarbon generation characteristics, such as gas/oil ratio, were reconstructed based on the burial history of the Bonan sub-sag and kinetic parameters of hydrocarbon generation of the shales.