The volcanic rocks of the Es3 (third member of the Shahejie) formation in the eastern sag of the Liaohe Basin are composed of basalt and trachyte, and the reservoir characteristics indicate complex reservoir space and strong heterogeneity. The latter is closely related to oil and gas reserves, and is important for evaluating reservoirs and predicting their oil and gas production. Electrical imaging data are obtained during such analysis and are subsequently transformed into a porosity map to obtain the porosity spectra and bin distribution. The results can then be used to qualitatively study the heterogeneity of the reservoir. In the present study, however, quantitative analysis is applied to evaluate the reservoir diversity of these volcanic rocks by calculating four heterogeneity parameters: the sorting index and the porosity variation coefficient, porosity ratio, and the heterogeneity coefficient. Combining the porosity spectra and porosity bin features enables the reservoir heterogeneity to be divided into three categories. The first is weak heterogeneity, which has both a sorting index and variation coefficient of <0.15, a porosity ratio of <2, and a porosity heterogeneity coefficient of <1.5. The second is moderate heterogeneity, with both a sorting index and porosity variation coefficient of 0.15–0.25, a porosity ratio of 2–4, and a porosity heterogeneity coefficient of 1.5–2.0. The third is strong heterogeneity, with both a sorting index and porosity variation coefficient of >0.25, a porosity ratio of >4, and a porosity heterogeneity coefficient of >2.0. In these three cases, the porosity spectra are dominated by unimodal distributions, bimodal distributions with tails, or multimodal distributions with tails, respectively. The heterogeneity of the volcanic reservoir was controlled by the lithology. The trachyte, from which most oil and gas is presently produced, is characterized mainly by weak heterogeneity, and the basalt is characterized mostly by moderate or strong heterogeneity. Thus, exploration conducted in the basalt layer should consider reservoirs with moderate heterogeneity and large pore sizes.

辽河盆地东部凹陷沙三（沙三段）组火山岩由玄武岩和粗面岩组成，储层特征表明储集空间复杂、非均质性强。后者与油气储量密切相关，对储层评价和油气产量预测具有重要意义。在这种分析过程中获得电成像数据，随后将其转换为孔隙度图，以获得孔隙度光谱和 bin 分布。结果可用于定性研究储层的非均质性。然而，在本研究中，通过计算四个非均质性参数，应用定量分析来评估这些火山岩的储层多样性：分选指数和孔隙度变化系数、孔隙度比和非均质系数。结合孔隙度谱和孔隙度仓特征，可以将储层非均质性分为三类。一是弱非均质性，分选指数和变异系数均<0.15，孔隙度比<2，孔隙度非均质系数<1.5。二是中度非均质性，分选指数和孔隙度变异系数均为0.15~0.25，孔隙度比为2~4，孔隙度非均质系数为1.5~2.0。三是非均质性强，分选指数和孔隙度变异系数均>0.25，孔隙度比>4，孔隙度非均质系数>2.0。在这三种情况下，孔隙度光谱分别以单峰分布、带尾的双峰分布或带尾的多峰分布为主。火山岩储层的非均质性受岩性控制。目前生产油气的粗面岩以弱非均质性为主，玄武岩以中度或强非均质性为主。因此，玄武岩层勘探应考虑非均质性中等、孔径大的储层。玄武岩以中度或强非均质性为主。因此，玄武岩层勘探应考虑非均质性中等、孔径大的储层。玄武岩以中度或强非均质性为主。因此，玄武岩层勘探应考虑非均质性中等、孔径大的储层。