中国不同类型盆地油气资源丰度统计特征及预测模型

油气资源丰度是油气资源评价的一项关键参数,取准资源丰度对于客观评价资源潜力十分重要。本文立足于类比刻度区进行统计分析,探索建立资源丰度预测模型的思路并开展研究;统计表明我国主要含油气盆地的常规油气资源普遍为中低丰度,并以特低丰度和低丰度资源为主,仅局部优越区块为高丰度。据此筛选刻度区数据,并按照裂谷、克拉通、前陆3种基本盆地类型分析常规油气资源丰度与相关地质参数的关系。不同类型盆地的油气资源丰度均与烃源岩生烃强度、圈闭面积系数、区域不整合次数3项主控地质参数具有显著的相关性,但不同类型盆地油气资源丰度与3项主控地质参数之间关系的变化趋势存在差异,拟合的单参数地质模型能够较好描述3项主控地质参数单独与不同类型盆地油气资源丰度的定量关系。由此建立了基于烃源岩生烃强度、圈闭面积系数、区域不整合次数3项主控地质参数的油气资源丰度预测模型,能够快速、准确求取不同类型盆地的常规油气资源丰度。预测模型在实际应用中效果较为理想,具有易操作、易推广的优点,实用价值较高。

Statistical characteristics and prediction models for oil and gas resources abundance in different types of Chinese basins

Oil and gas resources abundance is a key parameter for oil and gas resources assessment. Accurate resources abundance is very important for objective assessment of resource potential. This paper studies ideas of establishing resources abundance prediction models and conducts researches, based on the statistical analysis of the analog calibrated units; The statistical results show that the conventional oil and gas resources of major petroliferous basins in China are generally low-to-medium abundance, with super low abundance or low abundance resources making up most part, and only small-scale superior areas are high abundance. Based on these results, the calibrated units data is analyzed and the relationships between conventional oil and gas resources abundance and related geological parameters are analyzed according to three basic basin types: Rift Basin, Craton Basin and Foreland Basin. The analysis results show that oil and gas resources abundance of different types of basins has a significant correlation with three primary geological parameters including the hydrocarbon generation intensity of hydrocarbon source rocks, the trap area coefficient and the number of regional unconformities. But the relationships between oil and gas resources abundance and primary geological parameters in different types of Chinese basins are different. However, single-parameter geological models can describe the quantitative relationship between three primary geological parameters and oil and gas resources abundance in different types of basins more accurately. Accordingly, the prediction models of oil and gas resources abundance based on three primary geological parameters are established, including the hydrocarbon generation intensity of hydrocarbon source rocks, the trap area coefficient and the number of regional unconformities. They can quickly and accurately forecast the conventional oil and gas resources abundance in different types of basins. The prediction results of models are accurate in practical applications, which are easy to operate and popularize with a high practical value.