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塔中西北部奥陶系碳酸盐岩埋藏溶蚀作用 总被引:34,自引:5,他引:34
对塔中西北部奥陶系碳酸盐岩埋藏溶蚀发育的地质背景、充填矿物(岩石)学-地球化学特征进行了研究,埋藏溶蚀作用在碳酸盐岩储层发育中有重要作用。塔中西北部多期次构造活动和中-晚二叠世为主的岩浆—热液活动是埋藏溶蚀产生的基本条件;深埋或热液作用是以黄铁矿、绿泥石、石英、铁方解石、萤石等标型矿物和具有能发出明亮桔黄色光的富锰贫铁方解石胶结物、生长环带、铁白云石溶蚀等特征。方解石充填物中富含铁、锰、镁、锶等元素,δ18OPDB平均值为-6.6‰ ,δ13CPDB平均值为-2.0‰;流体包裹体均一温度为115~130℃和170~210℃,盐度为5%~7%/、8%~9%和12%~13% ,反映了埋藏成岩作用中有深部流体或循环流体参与。 相似文献
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鄂尔多斯盆地奥陶系马家沟组五段膏盐下白云岩储层形成的主控因素 总被引:1,自引:0,他引:1
近期勘探实践表明,鄂尔多斯盆地东部奥陶系马家沟组五段膏盐下白云岩具有良好的天然气勘探开发潜力。为此,综合岩心观察、薄片鉴定、物性分析及地球化学特征等资料,对其岩石学、储集空间和孔渗特征等开展了系统研究。结果表明,鄂尔多斯盆地奥陶系膏盐下储集层为孔隙型白云岩储层,纵向上分布在马五6亚段、马五7亚段和马五9亚段。马五6亚段储集层岩性主要为颗粒白云岩和斑状粉晶白云岩,马五7亚段和马五9亚段储集层岩性主要为颗粒白云岩和粉-细晶白云岩。三个储层段储集空间均以溶蚀孔洞为主,次为残余粒间孔、晶间溶孔、晶间孔和微裂缝,平均孔隙度分别为5.84%、6.81%和7.03%。沉积古地貌、海平面变化和准同生期大气淡水溶蚀作用等因素共同控制膏盐下白云岩储集层的发育与分布。研究认为位于盐岩边界线外侧的中央古隆起带和榆林-横山隆起带地势相对较高,颗粒滩沉积厚度大,在准同生期和浅埋藏期易于发生大气淡水溶蚀作用,其内部赋存的孔隙不易被膏盐岩充填,是盆地内膏盐下有利白云岩储集层的发育区。 相似文献
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Dragica Lj. Stojić Tomislav D. Grozdić Milica P. Marčeta Kaninski Aleksandar D. Maksić Nataša D. Simić 《International Journal of Hydrogen Energy》2006
Intermetallics phases along Mo–Pt phase diagram have been investigated as cathode materials for the production of hydrogen by electrolysis from water KOH solutions, in an attempt to increase the electrolytic process efficiency. These materials were compared with conventional cathodes (Fe and Ni), often used in the alkaline electrolysis, and also with the intermetallic Ti–Pt. An significant upgrade of the electrolytic efficiency using intermetallics in pure KOH electrolyte was achieved in comparison with conventional cathode materials. 相似文献
16.
J Stephen Robinson J Keith Syers Nanthi S Bolan 《Journal of the science of food and agriculture》1994,64(4):397-403
Laboratory experimental and literature data were integrated to develop a simple, conceptual model to describe and predict the dissolution of a reactive phosphate rock (Gafsa phosphate rock, GPR) in soils. The model showed that initial solution Ca concentration strongly influences the time required for a single application of GPR (at 30 kgP ha?1) to dissolve. The model predicts that all of the GPR will dissolve within a year of application in an unlimed, acid (pHw 4.5) loam. However, if the soil has previously been limed to (pHw 5.8, and contains permanent charge only, the model predicts that only about 50% of the GPR would have dissolved by the end of the second year after application. On the other hand, if a previously limed soil ((pHw 5.8) contains variable-charge components, the model predicts that virtually all of the GPR would have dissolved in this soil by the end of the second year after application. These results emphasise that, even in the presence of a high proton supply, solution Ca has an overriding influence on the dissolution of GPR. The faster rate of GPR dissolution in the limed soil with variable charge, compared to that in the limed soil with permanent charge only, demonstrates the ability of the variable-charge component of soil to act as a sink for some of the lime-derived Ca. According to the solubility product principle, this allows more GPR to dissolve. Because of the generally stronger buffering of soil for P than for Ca, a relatively large proportion of any P removed by leaching and plant uptake is buffered by the sorbed phase. Consequently, the influence of leaching and plant uptake on GPR dissolution is attributed primarily to the removal of the relatively less-strongly buffered Ca. 相似文献
17.
Junling Guo Huayu Pei Ying Dou Siyuan Zhao Guosheng Shao Jinping Liu 《Advanced functional materials》2021,31(18):2010499
Lithium-sulfur batteries (LSBs) are considered a promising next-generation energy storage device owing to their high theoretical energy density. However, their overall performance is limited by several critical issues such as lithium polysulfide (PS) shuttles, low sulfur utilization, and unstable Li metal anodes. Despite recent huge progress, the electrolyte/sulfur ratio (E/S) used is usually very high (≥20 µL mg−1), which greatly reduces the practical energy density of devices. To push forward LSBs from the lab to the industry, considerable attention is devoted to reducing E/S while ensuring the electrochemical performance. To date, however, few reviews have comprehensively elucidated the possible strategies to achieve that purpose. In this review, recent advances in low E/S cathodes and anodes based on the issues resulting from low E/S and the corresponding solutions are summarized. These will be beneficial for a systematic understanding of the rational design ideas and research trends of low E/S LSBs. In particular, three strategies are proposed for cathodes: preventing PS formation/aggregation to avoid inadequate dissolution, designing multifunctional macroporous networks to address incomplete infiltration, and utilizing an imprison strategy to relieve the adsorption dependence on specific surface area. Finally, the challenges and future prospects for low E/S LSBs are discussed. 相似文献
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以四川盆地川西坳陷上三叠统煤系地层的须家河组优质储层为对象,运用普通薄片、主体薄片、阴极发光、扫描电镜和激光拉曼探针分析,对其中发育的硅质碎屑溶蚀机理进行了探讨。川西须家河组硅质碎屑存在酸性地层水条件下有氟参与发生的溶蚀。在须家河组石英包裹体中测到的F成分,是F-、HF2-、未离解的HF分子及(HF)2等含F成分的总和,并且以未离解的HF分子和(HF)2为主。硅质溶蚀过程中,活性成分(HF)2或HF2-吸附于硅质颗粒表面,H+对反应起催化作用。其他矿物组合同时发生物质的交换与变化,包括长石、岩屑的溶蚀、硅质胶结等。硅质溶蚀的识别标志主要包括:地球化学标志、硅质颗粒的部分溶解、致密砂岩背景下颗粒间接触缝的开启和矿物组合标志。 相似文献
20.
More than in the case of the other major fertiliser elements the performance of phosphorus in fertilisers in dependent on the state of chemical combination of the element. As distinct from typical American practice where fully acidulated fertilisers are emphasised, some other countries have moved in part to production of materials of less than full acidulation where some reliance is placed on the reactivity of the original phosphate rock. Solutions of various aliphatic acids and their salts have been used as tests for the availability of phosphorus in fully acidulated fertilisers and, to a degree, for phosphate rocks themselves. Less than fully acidulated products are at present assessed in the same way as fully acidulated materials, but in this and other evaluations problems and anomalies arise which are discussed within the framework of a number of fertiliser systems. Analytical data are adduced which illustrate the effects of some extraneous cations on the results achieved which conflict with some previous opinions. Research towards a fuller understanding of the subject is suggested. 相似文献