碳酸盐岩生烃指标及生烃量评价的新认识

我国存在大量平均有机碳丰度很低（一般小于0．20％）、但仍能达到以往提出的碳酸盐岩烃源岩有机碳丰度下限（一般在0．10％）的碳酸盐岩，多年的勘探未发现其能生成原生工业性油气藏，表明该下限提得过低，原因在于传统观点笼统地认为碳酸盐岩中有机质生烃能力较高、碳酸盐岩排烃率高、提出过高的高演化阶段碳酸盐岩原始有机碳恢复系数，并且未考虑运移散失。在重新考虑这些因素后，认为烃源岩平均有机碳下限指标应主要由实际情况的类比来确定。碳酸盐岩烃源岩、高—过成熟阶段的烃源岩以及气源岩的有机碳丰度下限未必分别明显低于泥岩烃源岩、成熟阶段的烃源岩和油源岩，它们的平均有机碳含量都应在0．40％～0．50％以上。

碳酸盐岩生烃机制及生烃能力模糊评价方法

针对碳酸盐岩生烃机制及生烃能力的问题,对碳酸盐岩生烃能力与生烃机制展开研究,讨论了古老碳酸盐岩烃源岩能否有效生烃和排烃的问题.为了快速有效评价碳酸盐烃源岩生烃能力,对影响碳酸盐烃源岩生烃方面因素进行分析研究,采用极差标准变换对数据进行标准化,基于层次分析法确定了碳酸盐岩生烃能力评价指标体系.选取鄂尔多斯盆地西南缘碳酸盐岩样品对该评价指标体系进行验证,验证结果证明该评价指标体系准确合理.

The Study of Pollution of PAHs （Polycyclic Aromatic Hydrocarbons） in AI-Hilla River, Iraq by Using Bioindicator Freshwater Crab （Sesarma boulengeri Caiman）

The present study was used freshwater Crab （Sesarma boulengeri Caiman） as bioindicator to measured the PAHs levels in AI-Hilla River, Iraq, during the period from March 2010 to February 2011. Crab samples were collected from two sites on the AI-Hilla River. Sixteen of PAils compounds were identified seasonally in these samples. High mean value was （72.06 μg/g）, recorded by Dibenzo （a, h） anthracene （DbA） in Site 1 and low mean value was （0.36 μg/g） recorded by Anthracene （Ant） in Site 2. The study showed a clear variation in PAHs concentration independent from the seasons and locations. Site 1 recorded high value of HMW （high molecular weight） and LMW （low molecular weight） more than Site 2. The present study revealed that all PAHs compounds were from Pyrogenic Origin. Seven carcinogenic PAHs （cPAHs） were recorded in crab tissues that were collected from the AI-Hilla River. The TEF （toxicity equivalency factor） was calculated to toxicity equivalent crab concentration. From the results, the fresh water Crab Sesarma boulengeri is a good bioindicator to water pollution by PAHs.