油气资源分布的分形特征及应用

Fractal model for petroleum resource distribution and its application

根据南堡凹陷543个油藏、大民屯凹陷911个油藏、徐家围子凹陷16个气藏和全国43个大型油田储量的分布,发现不仅油气藏储量规模分布具有分形特征,储量丰度分布和储量空间分布也同样具有分形特征。据此,提出了基于随机模拟技术和傅立叶变换功率谱方法的油气资源空间分布的二维分形模型,用于描述区带油气资源的分布。利用该模型修正资源丰度、排除高风险区域、设置丰度经济界限,既可以预测不同含油气概率地区的资源量,又能够指出资源空间分布位置。在徐家围子凹陷预测出剩余天然气资源主要分布在凹陷东南部,为下步勘探指明了方向。

The reserves distribution of 543 oil pools in Nanpu Sag, 911 oil pools in Damintun Sag, 16 gas pools in Xujiaweizi Sag and 43 large oilfields in China indicates that the distribution of scale, abundance and spatial of reserves have fractal characteristics. A two dimensional fractal model for characterizing the geographic distribution of hydrocarbon accumulation was proposed on the basis of the stochastic simulation procedure and power spectrum approach. This model can be used to amend the resource abundance, truncate the high risk areas and shift some areas in less economy limit. The model can also be used to predict the resource potential in different exploration risks and provide information of possible geographic locations of undiscovered petroleum resources. The application of the model to Xujiaweizi Sag suggests that the gas residual resources mostly locate in the southeast of the sag. The predictions provide the useful information for future gas exploration in this area.