Abstract Subsurface hydrocarbon occurrences can be detected by clay mineral (CM) alteration at the surface as a consequence of hydrocarbon migration. This study analyzed CM alteration in an oil and gas (O&G) field in the West Tugu field, located in the northwest Java Basin of Indonesia. Landsat 8 OLI data acquired on 25 September 2015 and soil spectral reflectance (SSR) data recorded using analytical spectral devices (ASD) in March 2017 were processed using clay indices to analyze CM alteration. Soil samples from a field survey of the same area were also analyzed using X-ray diffraction (XRD) to identify their CM compositions. CM distribution was empirically modeled by integrating the SSR bands re-sampled to Landsat 8 OLI (SSRL) bands and the CM composition using the best subset regression method and regression analyses. The resulting model was applied to Landsat 8 OLI images to map the surface CM alteration. The results show that CM alteration observed in the O&G field is an indicator of hydrocarbon microseepage at the surface. These results can be used as a technique to identify prospective regions that contain hydrocarbons and differentiate from those that are barren, and could be useful for increasing the rate of drilling success.

中文翻译：

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油气田中粘土矿物的变化：表面表达、土壤光谱和 X 射线衍射数据的综合分析

摘要 地下碳氢化合物的存在可以通过碳氢化合物运移导致的地表粘土矿物 (CM) 蚀变来检测。本研究分析了位于印度尼西亚爪哇盆地西北部的 West Tugu 油田的油气 (O&G) 油田的 CM 蚀变。2015 年 9 月 25 日获得的 Landsat 8 OLI 数据和 2017 年 3 月使用分析光谱设备 (ASD) 记录的土壤光谱反射率 (SSR) 数据使用粘土指数进行处理，以分析 CM 改变。来自同一地区实地调查的土壤样品也使用 X 射线衍射 (XRD) 进行分析，以确定它们的 CM 组成。通过使用最佳子集回归方法和回归分析将重新采样的 SSR 波段与 Landsat 8 OLI (SSRL) 波段和 CM 组成相结合，对 CM 分布进行了经验建模。所得模型应用于 Landsat 8 OLI 图像以绘制表面 CM 变化图。结果表明，在 O&G 油田中观察到的 CM 蚀变是地表油气微渗流的一个指标。这些结果可用作识别含有碳氢化合物的预期区域并与贫瘠区域区分开来的技术，并可用于提高钻井成功率。