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941.
942.
If observed oil and gas field size distributions are obtained by random samplings, the fitted distributions should approximate that of the parent population of oil and gas fields. However, empirical evidence strongly suggests that larger fields tend to be discovered earlier in the discovery process than they would be by random sampling. Economic factors also can limit the number of small fields that are developed and reported. This paper examines observed size distributions in state and federal waters of offshore Texas. Results of the analysis demonstrate how the shape of the observable size distributions change with significant hydrocarbon price changes. Comparison of state and federal observed size distributions in the offshore area shows how production cost differences also affect the shape of the observed size distribution. Methods for modifying the discovery rate estimation procedures when economic factors significantly affect the discovery sequence are presented. A primary conclusion of the analysis is that, because hydrocarbon price changes can significantly affect the observed discovery size distribution, one should not be confident about inferring the form and specific parameters of the parent field size distribution from the observed distributions.This paper was presented at Emerging Concepts, MGUS-87 Conference, Redwood City, California, 13–15 April 1987. 相似文献
943.
944.
《中国科学D辑(英文版)》2006,(9)
1 Introduction China’s continent is a mountain-building zone made up of numerous micro-continental blocks and mini- continental blocks[1,2]. The continent has been sub- jected to the processes and evolution of three continual geodynamic systems of Paleo-Asia Ocean, Pa- leo-Tethys Ocean and Pacific Ocean[3]. The structural framework of China’s continent had been gradually finalized in the Neogene-Quaternary period owing to the India-Eurasia collision and its continuous com- pression[3], … 相似文献
945.
GL-1井完钻井深为6300.83 m,预计井底温度高达260 ℃。至完钻使用抗260 ℃高温白油基油包水钻井液施工6个月。应用结果表明:该钻井液具有抗温性(260 ℃ )、抗污染能力强、有利于井壁稳定、润滑性好和对油气储层损害程度小等优点。该井的成功为大庆油田下一步高温深层顺利勘探开发提供了安全有效的技术保障。 相似文献
946.
947.
Different types of crude oils have different light hydrocarbon compositional and geochemical characteristics. Based on the light hydrocarbon data from two kinds of oils, i.e., coal-generated oils and marine oils in China, light hydrocarbons in marine oils in the Tazhong area are generally relatively enriched in n-heptane, and coal-generated oils from the Turpan Basin are enriched in methylcyclohexane. The K1 values, reported by Mango (1987), range from 0.97 to 1.19 in marine oils, basically consistent with what was reported by Mango on light hydrocarbons in terms of the majority of the crude oil data. But the K1 values of coal-generated oils are particularly high (1.35-1.66) and far greater than those of marine oils; heptane values in marine oils, ranging from 32.3% to 45.4%, and isoheptane values, ranging from 1.9 to 3.7, are respectively higher than those of coal-generated oils, indicating that the oils are in the high-maturity stage. In addition, expulsion temperatures of coal-generated oils from the Turpan Basin are obviously lower than those of marine oils from the Tazhong area. 相似文献
948.
949.
Ozan Eskikaya Pinar Belibagli Raouf Bouchareb Zelal Isik Nadir Dizge 《洁净——土壤、空气、水》2024,52(3):2300083
Waste motor oil (WMO), which has no stable form or structure, causes major environmental problems and damage to the ecosystem once it is disposed to the environment. Because of the high toxicity of contents in such effluent, it must be treated before being discharged into the receiving environment. In recent years, the valorization and the use of waste materials to remove toxic pollutants is of great importance to researchers and diverse industries. In this study, the usability of waste welding powder (WWP) as an adsorbent for waste oil removal was investigated. For this purpose, investigating the usability of material, which is generated as industrial waste, in wastewater treatment will lead to the evaluation of waste. The effects of temperature, pH, WWP amount, and initial WMO amount were investigated. According to the adsorption studies, 1 g WWP/L of the processed adsorbent was able to effectively remove 95.05% of WMO (100 mg) at a pH of 2 at 30°C. Stereo microscopy images showed a large amount of oil adsorbed on the WWP surface. The different WWP properties were determined by adsorption isotherm (Harkins–Jura), kinetic (pseudo-second order), and thermodynamic (ΔG: −5.1 kJ mol–1) experiments. It is thought that WWP, which is a low-cost and waste material, can be used as a promising adsorbent in WMO removal. 相似文献
950.
多年冻土区输油管道工程中的(差异性)融沉和冻胀问题 总被引:17,自引:8,他引:17
多年冻土区石油和经济开发不断推动输油管道技术的发展,但是多年冻土区输油管道的(差异性)融沉和冻胀问题仍是关键性难题.寒区管道设计和施工必须考虑沿线的地形和环境条件对冻胀和融沉,以及相应的管道工程基础和结构整体性的影响.阿拉斯加输油管道工程取得成功的原因在于充足的科研投入、讨论和决策时间,以及最终采用的一系列创新设计来保护多年冻土和抑制融沉.这些研究围绕的关键问题是温热油管在多年冻土中的水热效应和差异性融沉和冻胀所导致的管道变形破坏,这些研究对可能出现问题的及早发现、充分理解和正确预测以及最终合理的设计、施工和维护至关重要.罗曼井和格拉线环境温度输油管道在20a左右的运营中,冻胀和融沉都比较显著.准确预测管道和围岩土的冻胀和融沉需要详细的观测研究和模拟试验相结合.在预测的基础上,针对具体问题抑制融沉和冻胀.成功设计、施工和运行寒区输油管道需要科学家、工程师、业界人士和管理部门密切合作. 相似文献