扎哈泉地区上干柴沟组致密油烃源岩测井评价方法

柴达木盆地扎哈泉地区新近系上干柴沟组下段近年来发现了大规模分布的致密油藏，但其源储配置关系尚不明确，急需建立有效的烃源岩评价方法。 综合分析烃源岩岩心实验室分析资料及其常规测井响应特征，优选声波时差、电阻率及铀为反映烃源岩有机质丰度的敏感参数，利用ΔlgR 法与铀-TOC 回归拟合法建立了烃源岩定性及 TOC 含量定量解释模型；同时，探索了利用特殊测井系列岩性扫描测井技术计算地层有机碳含量的方法。 研究表明，铀-TOC 回归拟合模型可以准确反映扎哈泉地区上干柴沟组下段烃源岩 TOC 含量的变化趋势，且计算简便，能够为该区致密油烃源岩评价提供可靠依据；岩性扫描测井方法在该区计算 TOC 含量精度稍低，但该方法不受环境因素控制，可以广泛应用于不同地区油藏岩性及烃源岩精细解释。

Logging evaluation methods of source rocks of tight oil of Upper Ganchaigou Formation in Zhahaquan area

In recent years, there have been found large-scale distribution of tight oil reservoir in the lower member of Upper Ganchaigou Formation（N₁g） in Zhahaquan area of Qaidam Basin, but the source-reservoir configuration is not clear. So it has an urgent need to establish effective source rock evaluation method. Based on source rock coring materials and comparative analysis of laboratory data with conventional logging response, the resistivity, acoustic and Uranium are proved to be the sensitive parameters reflecting the organic matter abundance of source rocks. ΔlgR method and Uranium-TOC regression method were used to establish qualitative and quantitative interpretation model. At the same time, the method of evaluating the organic matter abundance through Litho Scanner was explored. The quantitative interpretation model according to Uranium-TOC regression method is proved to be the most efficient way to reflecting the change trend of TOC of the lower member of Upper N₁g in Zhahaquan area, and the calculation is simple and convenient, so it can provide a reliable basis for evaluating the source rocks of the tight oil in this area. The calculation accuracy of TOC according to Litho Scanner is slightly lower affected by the geological condition of this area, but this method is not controlled by regional environmental factors, and can be widely used in fine interpretation of lithology and source rocks of reservoirs in different areas.