琼东南盆地深水区中央峡谷油气指标的多重分形性分析

不同形态的多重分形频谱可用于含油气远景评价和油气分布规律的研究,本文运用多重分形矩方法对中央峡谷体系已钻井获得的2 684个数据13项油气指标的多重分形谱函数形态特征进行了研究。结果表明,琼东南盆地深水区中具有较强多重分形特征的指标,具有多重分形谱函数宽而连续的特征,成一右偏弧形状;而其他指标则显示较弱或单一分形特征。将这一结果与常用的统计方法因子分析结果做对比,结果表明,通过多重分形分析对这几项油气指标的分组结果与常规的统计分析结果基本吻合。为更进一步探究这几种主要油气指标在油气指示中的权重,采用主成分分析法对这几种指标进行分析,结果表明在琼东南盆地深水区,异丁烷、正丁烷、异戊烷为圈定油气远景区的重要指标。

Multifractal properties of oil and gas indexes in central canyon of Qiongdongnan Basin deepwater area

Different Multifractal spectrum can be used for petroleum prospect evaluation. A typical multifractal model called the method of moments is employed to study the distribution patterns based on the multifractal spectrum forms obtained from 13 oil and gas indexes and 2 684 data in the deepwater area of central canyon of the Qiongdongnan basin. The results show that the indicators with strong multi-fractal characteristics in deepwater have wide and continuous fractal spectrum function features, forming a right side arc shape. While other indicators display weak or single fractal feature. Comparing the result with the one from factor analysis, shows that these results are generally consistent. In order to further examine the weights of these oil and gas indexes, principal component analysis was used to analyze these indicators. The results indicate that isobutane, normal butane, iso-pentane is important indicators to delineate hydrocarbon in the deepwater area.