Segregation of sediments for oil and gas potential is a complex task. In this study three oil wells i.e. Dhurnal, Pariwali and Pindori were analyzed for oil and gas potential using geophysical well logs and isotopic analysis. 50 sediments (Eocene to Early Permian) from three productive oil wells were analyzed for source and depositional environment. The Eocene Chorgali limestone and Eocene Sakesar limestone showed good permeability (Spontaneous Potential log) with interbedded shale (Gamma Ray log) while Paleocene Patala and Early Permian Sardhai formation indicated low permeability and good shale presence. Isotopic ( 13 δC and 15 δN) and elemental analysis suggested that the source of organic matter was C 3 plants with anoxic carbonate depositional setting. Total organic carbon and Rock Eval parameters (S1 and S2) indicated a good quantity of organic matter. Ratio based on Rock Eval parameters indicated the dominant potential for oil expulsion in Paleocene Patala and Early Permian Sardhai formation. Hydrogen index and oxygen index indicated the Type-II/III kerogen as a source of organic matter. The sediments were thermally mature and within the oil expulsion window. Based on results, Eocene Chorgali limestone has a good reservoir while Paleocene Patala shale has a good source rock character.

中文翻译：

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巴基斯坦 Potwar 盆地早二叠世、古新世和始新世沉积物的地球化学分离：I 源和沉积环境的地球物理和同位素分析

分离沉积物以获取油气潜力是一项复杂的任务。在这项研究中，使用地球物理测井和同位素分析对三口油井，即 Dhurnal、Pariwali 和 Pindori 进行了油气潜力分析。分析了来自三个生产油井的 50 个沉积物（始新世至早二叠世）的来源和沉积环境。始新世 Chorgali 石灰岩和始新世 Sakesar 石灰岩与页岩互层（伽玛射线测井）显示出良好的渗透性（自发势测井），而古新世 Patala 和早二叠世 Sardhai 地层显示出低渗透性和良好的页岩存在。同位素（ 13 δC 和 15 δN）和元素分析表明有机质来源为碳酸盐缺氧沉积环境的C 3 植物。总有机碳和岩石评估参数（S1 和 S2）表明有机质含量很高。基于岩石评价参数的比率表明古新世帕塔拉和早二叠世 Sardhai 地层的主要排油潜力。氢指数和氧指数表明Ⅱ/Ⅲ型干酪根是有机质的来源。沉积物热成熟并在排油窗口内。结果表明，始新世乔加里灰岩储集层较好，古新世帕塔拉页岩烃源岩特征较好。沉积物热成熟并在排油窗口内。结果表明，始新世乔加里灰岩储集层较好，古新世帕塔拉页岩烃源岩特征较好。沉积物热成熟并在排油窗口内。结果表明，始新世乔加里灰岩储集层较好，古新世帕塔拉页岩烃源岩特征较好。