[Objective] In the Kuqa Depression, the Triassic and Jurassic periods feature five sets of source rock sequences that developed as alternating lake and swamp facies. Based on lithology, these sequences can be divided into coal, carbonaceous mudstone, and dark mudstone. The source rocks are characterized by high TOC abundance, significant thickness, and extensive distribution. Due to the multiple vertically distributed layers of source rocks and the strong heterogeneity in lithological distribution, conventional methods like the ΔlgR method have shown poor performance in TOC logging quantification. [Methods] To better understand the hydrocarbon resource potential and assess the reserves in the Kuqa Depression, this study first identified the lithological characteristics of the source rocks through core analysis. Further geological characterization of the source rocks was achieved via geochemical analysis data. Initially, the ΔlgR method was applied to quantitatively evaluate TOC logging, and LithoScanner logging was used for lithological identification of the source rocks. Further, LithoScanner logging was employed to achieve quantitative TOC logging evaluation. [Results] Overall, the Triassic and Jurassic periods are dominated by type II1, II2, and III organic matter, with medium to high maturity, and the quality of these source rocks ranges from medium to good. The method of using LithoScanner logging to identify different lithological source rocks and quantitatively evaluate TOC demonstrated significantly higher accuracy compared to the ΔlgR method. [Conclusion] The research findings provide valuable guidance for assessing the hydrocarbon resource potential in the Kuqa Depression and expand the application scope of LithoScanner logging data.
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