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41.
The organic geochemical methods of hydrocarbon prospecting involve the characterization of sedimentary organic matter in terms of its abundance, source and thermal maturity, which are essential prerequisites for a hydrocarbon source rock. In the present study, evaluation of organic matter in the outcrop shale samples from the Semri and Kaimur Groups of Vindhyan basin was carried out using Rock Eval pyrolysis. Also, the adsorbed low molecular weight hydrocarbons, methane, ethane, propane and butane, were investigated in the near surface soils to infer the generation of hydrocarbons in the Vindhyan basin. The Total Organic Carbon (TOC) content in shales ranges between 0.04% and 1.43%. The S1 (thermally liberated free hydrocarbons) values range between 0.01–0.09 mgHC/gRock (milligram hydrocarbon per gram of rock sample), whereas the S2 (hydrocarbons from cracking of kerogen) show the values between 0.01 and 0.14 mgHC/gRock. Based on the Tmax (temperature at highest yield of S2) and the hydrogen index (HI) correlations, the organic matter is characterized by Type III kerogen. The adsorbed soil gas, CH4 (C1), C2H6 (C2), C3H8 (C3) and nC4H10, (nC4), concentrations measured in the soil samples from the eastern part of Vindhyan basin (Son Valley) vary from 0 to 186 ppb, 0 to 4 ppb, 0 to 5 ppb, and 0 to 1 ppb, respectively. The stable carbon isotope values for the desorbed methane (δ13C1) and ethane (δ13C2) range between −45.7‰ to −25.2‰ and −35.3‰ to −20.19‰ (VPDB), respectively suggesting a thermogenic source for these hydrocarbons. High concentrations of thermogenic hydrocarbons are characteristic of areas around Sagar, Narsinghpur, Katni and Satna in the Son Valley. The light hydrocarbon concentrations (C1–C4) in near surface soils of the western Vindhyan basin around Chambal Valley have been reported to vary between 1–2547 ppb, 1–558 ppb, 1–181 ppb, 1–37 ppb and 1–32 ppb, respectively with high concentrations around Baran-Jhalawar-Bhanpur-Garot regions (Kumar et al., 2006). The light gaseous hydrocarbon anomalies are coincident with the wrench faults (Kota – Dholpur, Ratlam – Shivpuri, Kannod – Damoh, Son Banspur – Rewa wrench) in the Vindhyan basin, which may provide conducive pathways for the migration of the hydrocarbons towards the near surface soils. 相似文献
42.
43.
山东金亭岭金矿矿床地球化学异常分带模型 总被引:1,自引:0,他引:1
通过对山东金亭岭金矿各类微量元素和烃类组分在该矿床不同中段的含量变化以及在纵向上的异常展布和富集规律进行分析和总结,建立了该矿床的地球化学叠加异常分带理想模型,得出矿床地球化学异常轴向分带序列确定为:甲烷、乙烷、丙烷、正丁烷、异丁烷、乙烯、丙烯、Sb(前缘晕)→As、Hg(矿头晕)→Au、Ag、Pb、Zn、Cu、Mn(矿中晕)→Co、Ni、Mo、Bi(矿尾晕),并总结了找矿预测标志,为其深部找矿预测提供了一定的科学借鉴依据。 相似文献
44.
伊拉克AHDEB油田油藏成藏规律对油田后期开发具有重要意义, 与埋藏史相结合的流体包裹体研究是揭示油藏油气成藏期次和时间的有效手段.利用伊拉克AHDEB油田白垩系油藏储层样品对流体包裹体特征进行了分析, 并且通过流体包裹体的显微观察、荧光颜色、单一包裹体的红外光谱和均一温度测定, 结合地质背景对该油田的油充注期次进行了研究.研究表明, 油包裹体以发绿色和黄绿色荧光为主, 少数发浅黄色和黄褐色荧光.油包裹体的显微傅立叶红外光谱测定结果计算的CH2a/CH3a、Xinc、Xstd可划分油的成熟度, 表明存在两种成熟度的油.最后, 根据均一温度测定结果, 结合埋藏史和热史, 认为该油田可能存在4期油充注成藏相关的流体活动: 第1成藏期发生在95.0~96.5Ma, 相当于晚白垩世早期; 第2成藏期为71.0~78.5Ma, 相当于晚白垩世晚期, 第1期和第2期烃源岩排烃规模小, 产生中-重质油, 后期遭受氧化而形成沥青; 第3成藏期发生在14.0~15.0Ma, 相当于中中新世, 处于生排烃高峰期, 为主要成藏期; 第4期发生在10.0Ma左右, 与第3期为多幕连续充注. 相似文献
45.
应用热重-质谱(TG-MS)联用技术对风化煤(WC)及其腐植酸提取后残渣(WCR)的热解行为进行了研究,分析了非烃类(H2、H2O、CO和CO2)、低碳烃类(CH4、C3H6和C3H7)和芳烃类(C6H6)的实验结果,并利用Coast-Redfern积分法对其热解和烃类生成动力学进行了探讨,获得了热解过程和烃类生成动力学参数。结果表明:热解过程中风化煤的质量损失率(38.9%)略大于其腐植酸提取后残渣(36.6%);除CO和CO2外,残渣中非烃类、低碳烃类和芳烃类产物的逸出量都稍微或显著多于风化煤中各类组分的逸出量。用Coast-Redfern积分法求得的动力学参数很好地解释了这一结果。 相似文献
46.
YANG Minghui LI Liang ZHOU Jin JIA Huichong SUN Xiao GONG Ting DING Chao 《《地质学报》英文版》2015,89(5):1636-1648
The hydrocarbon potential of the Hangjinqi area in the northern Ordos Basin is not well known, compared to the other areas of the basin, despite its substantial petroleum system.Restoration of a depth-converted seismic profile across the Hangjinqi Fault Zone(HFZ) in the eastern Hangjinqi area shows one compression that created anticlinal structures in the Late Triassic, and two extensions in ~Middle Jurassic and Late Early Cretaceous, which were interrupted by inversions in the Late Jurassic–Early Early Cretaceous and Late Cretaceous, respectively.Hydrocarbon generation at the well locations in the Central Ordos Basin(COB) began in the Late Triassic.Basin modeling of Well Zhao-4 suggests that hydrocarbon generation from the Late Carboniferous–Early Permian coal measures of the northern Shanbei Slope peaked in the Early Cretaceous, predating the inversion in the Late Cretaceous.Most source rocks in the Shanbei Slope passed the main gas-migration phase except for the Hangjinqi area source rocks(Well Jin-48).Hydrocarbons generated from the COB are likely to have migrated northward toward the anticlinal structures and traps along the HFZ because the basin-fill strata are dipping south.Faulting that continued during the extensional phase(Late Early Cretaceous) of the Hangjinqi area probably acted as conduits for the migration of hydrocarbons.Thus, the anticlinal structures and associated traps to the north of the HFZ might have trapped hydrocarbons that were charged from the Late Carboniferous–Early Permian coal measures in the COB since the Middle Jurassic. 相似文献
47.
As an in situ, simple and passive technology, Permeable Reactive Barrier (PRB) is becoming widely used in groundwater remediation. Based on its definition and development process, the development of PRB can be divided into two stages: The traditional zero-valent iron PRB before 2000 and the PRB composed of novel mixed media after 2000. With the rapid worsening of groundwater pollution, the increasing application of PRB and the rapid development of materials science, the development of PRB technology in future will be mainly focused on the investigation of mixed and novel media, the design of mixed PRBs, the combination of PRB technology with other remediation technology, and the long term monitoring and management of PRB projects. 相似文献
48.
We investigated the distribution of lipids in Lower Triassic sedimentary rocks (252–247 myr) from South China, including a shallow water microbialite in the uppermost section of the outcrop. Archaeal derived hydrocarbons were the major constituents of the microbialite from the latest Early Triassic. Among these, we detected (i) abundant C40 acyclic and monocyclic biphytanes (possibly derived from glycerol dialkyl glycerol tetraether lipids) and their degradation products, C30–39 pseudohomologues and (ii) a C25 head-to-tail linked (regular) isoprenoid hydrocarbon [possibly derived from dialkyl glycerol diether lipids (DGDs)] and its degradation products, C21–24 pseudohomologues and abundant pristane and phytane. Through combination of compound-specific stable carbon isotope analysis of isoprenoid hydrocarbons, which had average δ13C values of −35‰ to −30‰, and their molecular distribution, it was not possible to unambiguously define the archaeal source for the biphytanes in the microbialite. The δ13C values for pristane and phytane were similar to those for head-to-tail linked C21–25 isoprenoids; potential source organisms for these compounds were halophilic archaea. Except for methane seep microbialites, no other ancient or recent phototrophic microbialites have been reported to contain predominantly archaeal isoprenoid hydrocarbons. Our findings suggest the presence of a new type of microbialite. 相似文献
49.
From a determination of the transformation matrix for three pyrolysis product experimental data sets, an examination is given of both the applicability of the laboratory experimental data to the modeling of oil cracking in a sedimentary basin, and of the appropriateness of an inverse model. The results of the laboratory experimental data sets, which were done under different thermodynamic conditions and using different sources, show that the transformation matrix varies over each data set and also with time. Therefore, it is necessary to check the data sets before applying them to a basin for hydrocarbon modeling. The laboratory experimental data taken at lower temperature and over longer times appear more pertinent for the construction of an oil-cracking kinetic model suitable for geologic conditions. 相似文献
50.