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Exploration Strategies for Complex Fault Block Reservoirs in the Subei Basin 被引量:2
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作者 Liu Xiaoping Yang Xiaolan Liu Yurui 《Petroleum Science》 SCIE CAS CSCD 2007年第1期30-35,共6页
The geological background of the Subei basin is that of small relief subsidence, low geothermal gradient, multi-sedimentary hiatuses, intense reconstruction of the basin, frequent magmatic activity, and a unique combi... The geological background of the Subei basin is that of small relief subsidence, low geothermal gradient, multi-sedimentary hiatuses, intense reconstruction of the basin, frequent magmatic activity, and a unique combination of source rock and reservoir. This geological background resulted in characteristics such as many small fault blocks, multiple oil-bearing formations, scattered oil distribution, mini- to small-sized reservoirs, and difficulties in exploration. Aimed at such characteristics, an effective exploration strategy was adopted, and the oil reserves, production and economic benefits of the Jiangsu oilfield were significantly increased. This exploration strategy included understanding the hydrocarbon generation mechanism of source rocks, progressive evaluation of oil resources, comprehensive research on the faulted systems, the distribution of oil reservoirs and their controlling factors. The techniques used included integration of acquisition, processing and interpretation with 3-D seismics as the core technology, trap description and evaluation, directional drilling and cluster drilling, integration of cuttings logging, gas chromatographic logging and geochemical logging, and integration of early reservoir description and progressive exploration and development. This strategy could be guidance for other complex fault blocks. 展开更多
关键词 complex fault block petroleum exploration technical strategy Subei Basin
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Polymerization of lactide and synthesis of block copolymer catalyzed by copper(Ⅱ) Schiff base complex 被引量:4
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作者 Anita Routaray Somanath Mantri +2 位作者 Nibedita Nath Alekha Kumar Sutar Tungabidya Maharana 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第12期1763-1766,共4页
In the present investigation, the novel copper Schiff base complex was synthesized and its catalytic activity was evaluated for the ring-opening polymerization (ROP) of lactide and block polymerization of poly(lact... In the present investigation, the novel copper Schiff base complex was synthesized and its catalytic activity was evaluated for the ring-opening polymerization (ROP) of lactide and block polymerization of poly(lactide) with po/y(ethylene glycol)methyl ether, 展开更多
关键词 ROP LACTIDE Schiff Base Copper complex PLA block polymer
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Farewell faults in complex fault blocks with multi-technological integration
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作者 YANG Guang-lin HU Xiao-hui YAN Jing-hua 《Journal of China University of Mining and Technology》 EI 2008年第2期229-231,共3页
In the middle and second half of oilfield development,further exploration and development of petroleum reservoirs in complex fault blocks are major tasks.Based on the characteristics of fully developed farewell faults... In the middle and second half of oilfield development,further exploration and development of petroleum reservoirs in complex fault blocks are major tasks.Based on the characteristics of fully developed farewell faults in the Wenweigu oil field and the data from 3D earthquakes,RFT,HDT and other techniques,farewell faults and their distribution were identified.Conformation of the fault blocks has been provided and the precision of describing the farewell faults improved.Research technology of farewell faults has applied these methods in this region. 展开更多
关键词 farewell fault complex fault block stratigraphic correlation EARTHQUAKE RFT
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Crystalline inclusion complexes formed between the drug diflunisal and block copolymers
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作者 Zhi Zhong Xiaotong Yang +4 位作者 Xiao-Bin Fu Ye-Feng Yao Bao-Hua Guo Yanbin Huang Jun Xu 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第6期1268-1275,共8页
The solid form of drugs plays a central role in optimizing the physicochemical properties of drugs,and new solid forms will provide more options to achieve the desirable pharmaceutical profiles of drugs.Recently,certa... The solid form of drugs plays a central role in optimizing the physicochemical properties of drugs,and new solid forms will provide more options to achieve the desirable pharmaceutical profiles of drugs.Recently,certain drugs have been found to form crystalline inclusion complexes(ICs) with multiple types of linear polymers,representing a new subcategory of pharmaceutical solids.In this study,we used diflunisal(DIF) as the model drug host and extended the vip of drug/polymer ICs from homopolymers to block copolymers of poly(ethylene glycol)(PEG) and poly(s-caprolactone)(PCL).The block length in the vip copolymers showed a significant influence on the formation,thermal stability and dissolution behavior of the DIF ICs.Though the PEG block could hardly be included alone,it could indeed be included in the DIF ICs when the PCL block was long enough.The increase of the PCL block length produced IC crystals with improved thermal stability.The dissolution profiles of DIF/block copolymer ICs exhibited gradually decreased aqueous solubility and dissolution rate with the increasing PCL block length.These results demonstrate the possibility of using drug/polymer ICs to modulate the desired pharmaceutical profiles of drugs in a predictable and controllable manner. 展开更多
关键词 Pharmaceutical solid forms Inclusion complexes Drugs block copolymers Thermal stability Aqueous solubility Dissolution profiles
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A New Generalized Complex Orthogonal Space-Time Block Codes
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作者 单红梅 胡光锐 《Journal of Shanghai University(English Edition)》 CAS 2005年第3期241-243,共3页
Recent research challenges in the wireless communication include the usage of diversity and efficient coding to improve data transmission quality and spectral efficiency. Space diversity uses multiple transmitting and... Recent research challenges in the wireless communication include the usage of diversity and efficient coding to improve data transmission quality and spectral efficiency. Space diversity uses multiple transmitting and/or receiving antennas to create independent fading channels without penalty in bandwidth efficiency. Space-time block coding is an encoding scheme for communication over Rayleigh fading channels using multiple transmitting antennas. Space-time block codes from complex orthogonal designs exist only for two transmitting antennas. This paper generalizes a new complex orthogonal space-time block code for four transmitting antennas, whose decoding complexity is very low. Simulations show that the generalized complex orthogonal space-time block code has low bit error rate, full rate and possibly large diversity. 展开更多
关键词 space diversity space-time block code multiple antennas generalized complex orthogonal designs.
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LBlock码的不可能差分密码性能分析 被引量:4
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作者 郭建胜 罗伟 +1 位作者 张磊 郭渊博 《电子与信息学报》 EI CSCD 北大核心 2013年第6期1516-1519,共4页
该文分析研究了LBlock分组密码算法的不可能差分性质。基于LBlock算法的轮函数结构和部分密钥分别猜测技术,给出了21轮和22轮的LBlock算法的不可能差分分析方法。攻击21轮LBlock算法所需的数据量约为262,计算量约为262次21轮加密;攻击22... 该文分析研究了LBlock分组密码算法的不可能差分性质。基于LBlock算法的轮函数结构和部分密钥分别猜测技术,给出了21轮和22轮的LBlock算法的不可能差分分析方法。攻击21轮LBlock算法所需的数据量约为262,计算量约为262次21轮加密;攻击22轮LBlock算法所需的数据量约为262.5,计算量约为263.5次22轮加密。与已有的结果相比较,分析所需的计算量均有明显的降低,是目前不可能差分分析攻击LBlock的最好结果。 展开更多
关键词 分组密码 不可能差分分析 Lblock分组密码 计算复杂性
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粤西高州地区变质基底的原岩特征、变质演化及其构造意义
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作者 陈德源 尹常青 +3 位作者 钱加慧 吴尚京 乔恒忠 王晓曼 《岩石学报》 北大核心 2026年第1期186-206,共21页
高州地区地处华南板块华夏地块西南部,位于云开地体的核心区域。本研究在高州地区开展了详细的150000地质填图工作,针对含/不含石榴子石黑云斜长片麻岩进行了地球化学分析,并对石榴黑云斜长片麻岩开展了精细的岩相学、地球化学、矿物化... 高州地区地处华南板块华夏地块西南部,位于云开地体的核心区域。本研究在高州地区开展了详细的150000地质填图工作,针对含/不含石榴子石黑云斜长片麻岩进行了地球化学分析,并对石榴黑云斜长片麻岩开展了精细的岩相学、地球化学、矿物化学分析以及相平衡模拟研究。结果显示含/不含石榴子石黑云斜长片麻岩均呈现出高SiO_(2)、Al_(2)O_(3),低TiO_(2),低Na_(2)O/K_(2)O、Fe_(2)O^(T)_(3)/K_(2)O,铕负异常,高(La/Yb)N比值等特征,并富集Rb、Th、U而亏损Nb、Ta、Zr、Hf等高场强元素。其原岩可能为地表的一套含粘土质杂砂岩建造,夹少量的长石砂岩,属于副片麻岩。岩相学观察表明,石榴黑云斜长片麻岩经历了两个变质阶段。峰期矿物组合为石榴子石+斜长石+黑云母+钾长石+白云母+熔体+石英,退变质矿物组合为斜长石+黑云母+钾长石+白云母+石英。通过矿物成分分析和相平衡模拟,限定了峰期的温压条件为740~750℃、1.15~1.2GPa,退变质温度条件为<650℃。样品具有顺时针P-T轨迹和峰后降温减压的特征,表明这些岩石经历了早期地壳增厚以及随后的快速折返/隆升过程。前人年代学研究数据表明华夏地块的角闪-麻粒岩相的变质作用发生于460~400Ma。结合前人研究结果,本文表明高州地区的变质基底岩石在早古生代经历了高压角闪岩相变质作用,指示云开地体被卷入了加里东期的地壳增厚事件。 展开更多
关键词 石榴黑云斜长片麻岩 原岩特征 变质P-T轨迹 高州杂岩 华夏地块
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Paleoproterozoic Potassic Granitoids in the Sushui Complex from the Zhongtiao Mountains,Northern China:Geochronology,Geochemistry and Petrogenesis 被引量:15
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作者 TIAN Wei LIU Shuwen ZHANG Huafeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期875-885,共11页
Paleoproterozoic potassic granitoids in the southern Sushui Complex from the Zhongtiao Mountains yielded SHRIMP zircon U-Pb ages of 1968-1944 Ma. Lithologically, the potassic granitoid series consists chiefly of monzo... Paleoproterozoic potassic granitoids in the southern Sushui Complex from the Zhongtiao Mountains yielded SHRIMP zircon U-Pb ages of 1968-1944 Ma. Lithologically, the potassic granitoid series consists chiefly of monzodiorite, quartz monzonite and syenogranite. Their trace elements and Sm-Nd isotope characteristics indicate that they were derived from partial melting of Archean TTG rocks in an overthickened continental crust. Petrogenesis of this potassic granitoid series implies a collisional environment within the Trans-North China Orogen in the Paleoproterozoic, which supports a tectonic model of Eastern and Western Continental Blocks being amalgamated in the Paleoproterozoic. 展开更多
关键词 Sushui complex Zhongtiao block Trans-North China Orogen potassic granitoid zircon U-Pb Sm-Nd isotope PALEOPROTEROZOIC
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Ring-opening Copolymerization of ε-Caprolactone and δ-Valerolactone Catalyzed by a 2,6-Bis(amino)phenol Zinc Complex 被引量:2
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作者 Qian Hu Su-Yun Jie +1 位作者 Pierre Braunstein Bo-Geng Li 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2020年第3期240-247,I0006,共9页
In combination with methyllithium,a 2,6-bis(amino)phenol zinc complex 1 was used in the ring-opening polymerization ofδ-valerolactone in the absence or presence of benzyl alcohol and showed high efficiency,mainly pro... In combination with methyllithium,a 2,6-bis(amino)phenol zinc complex 1 was used in the ring-opening polymerization ofδ-valerolactone in the absence or presence of benzyl alcohol and showed high efficiency,mainly producing cyclic and linear polyvalerolactones,respectively.On the basis of homopolymerization,the ring-opening copolymerization ofε-caprolactone andδ-valerolactone was investigated.The P(CL-co-VL)random copolymers,PCL-b-PVL and PVL-b-PCL diblock copolymers,were prepared by varying the feeding strategy(premixing or sequential feeding).The copolymer composition was adjusted by varying the feeding ratio of two monomers.The structure and thermal properties of obtained polymers were characterized by GPC,1 H-NMR,13 C-NMR,MALDI-TOF mass spectroscopy,and DSC,respectively. 展开更多
关键词 Zn complex COPOLYMERIZATION block copolymer Random copolymer
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Differential diagnosis of tachycardia with a typical left bundle branch block morphology 被引量:1
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作者 Jeffrey S Neiger Richard G Trohman 《World Journal of Cardiology》 CAS 2011年第5期127-134,共8页
The evaluation of wide QRS complex tachycardias (WCT)remains a common dilemma for clinicians.Numerous algorithms exist to aid in arriving at the correct diagnosis.Unfortunately,these algorithms are difficult to rememb... The evaluation of wide QRS complex tachycardias (WCT)remains a common dilemma for clinicians.Numerous algorithms exist to aid in arriving at the correct diagnosis.Unfortunately,these algorithms are difficult to remember,and overreliance on them may prevent cardiologists from understanding the mechanisms underlying these arrhythmias.One distinct subcategory of WCTs are those that present with a"typical"or"classic" left bundle branch block pattern.These tachycardias may be supraventricular or ventricular in origin and arise from functional or fixed aberrancy,bystander or participating atriofascicular pre-excitation,and bundle branch reentry.This review will describe these arrhythmias,illustrate their mechanisms,and discuss their clinical features and treatment strategies. 展开更多
关键词 TYPICAL left BUNDLE branch block Wide complex TACHYCARDIA BUNDLE branch REENTRANT VENTRICULAR TACHYCARDIA
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L-Lactide Homopolymerization and Copolymerization with ε-Caprolactone by Tetrahydrosalen Stabilized Yttrium Borohydride Complex
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作者 Yan-hua Wang Dong Xiang +3 位作者 Rong Ren Jin Luo 孙维林 Zhi-quan Shen 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2014年第11期1500-1506,共7页
L-lactide(LLA) homopolymerization and copolymerization with ε-caprolactone(CL) in toluene initiated by tetrahydrosalen-supported yttrium borohydride complex were systematically investigated. A possible mechanism ... L-lactide(LLA) homopolymerization and copolymerization with ε-caprolactone(CL) in toluene initiated by tetrahydrosalen-supported yttrium borohydride complex were systematically investigated. A possible mechanism of LLA homopolymerization was proposed according to the 1H-NMR result. In addition, PCL-b-PLLA copolymers were synthesized by sequential addition of monomers and their structure was characterized by GPC, 1H-NMR and 13C-NMR. 展开更多
关键词 Yttrium borohydride complex HOMOPOLYMERIZATION block copolymer.
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Drug-polymer inclusion complex as a new pharmaceutical solid form
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作者 Xiaotong Yang Zhi Zhong +1 位作者 Jun Xu Yanbin Huang 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第11期2099-2104,共6页
The solid forms of drugs play a central role in controlling their physicochemical properties and consequently the bioavailability. Multiple types of drug solid forms have been developed to achieve the desirable pharma... The solid forms of drugs play a central role in controlling their physicochemical properties and consequently the bioavailability. Multiple types of drug solid forms have been developed to achieve the desirable pharmaceutical profiles, but new solid forms will provide more options for the solid-state property optimization and hence are highly desirable. This review focuses on a new pharmaceutical solid form, drug-polymer inclusion complexes (ICs), and summarizes their structural features, structure- property relationships, as well as potential pharmaceutical applications 展开更多
关键词 Pharmaceutical solid forms Crystalline inclusion complex Thermal stability Dissolution profiles Homopolymers block copolymers
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Geochemistry of the Granites in the Tamuqi Area on the Southern Margin of Tarim Block
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作者 朱立华 张传林 +2 位作者 赵宇 郭坤一 董永观 《Chinese Journal Of Geochemistry》 EI CAS 2001年第4期343-350,共8页
This study shows that the intrusive rocks distributed in the Aoyiqieke-Tamuqi area on the southern margin of the Tarim Block are composed of gabbro, diorite, granodiorite and granite, which constitute regionally a nea... This study shows that the intrusive rocks distributed in the Aoyiqieke-Tamuqi area on the southern margin of the Tarim Block are composed of gabbro, diorite, granodiorite and granite, which constitute regionally a nearly EW-trending tectono-magmatic belt. Petrochemically the diorite, granodiorite and granite belong to the calc-alkaline, high-K series, with Na 2O/K 2O ratios varying between 0.83 and 2.63. M/F ratios in the diorite are within the range of 0.44- 0.70 and those of the granodiorite (granite) are 0.45- 0.87. Petrochemistry data show that the intrusive complexes are of the I type and their ΣREE is slightly variable, within the range of 178.31- 229.01×10 -6. The LREE/HREE ratios of the diorite and granite are 3.78- 5.13 and 6.69- 7.66, respectively. The plutons usually show moderate negative Eu anomalies with δEu values ranging from 0.53 to 0.82, showing almost no difference among different rocks. The (La/Yb) N values of diorite and granite are 12.39- 14.86 and 22.07- 26.03, respectively. The diorite and granite possess very similar REE distribution patterns, indicating that they were both derived from the same source. As for their trace element ratios, the diorite has higher Nb/Ta ratios than the granite, which are 15.73- 17.16 and 12.03- 15.01, respectively. It can be seen that the Nb/Ta ratios of the diorite are much closer to the average mantle ( 17.5). Their Zr/Hf ratios are very close to each other, within the range of 29-34. Th/Y ratios in the diorite are 0.42- 0.80 (all less than unity) while those of the granite are 1.02- 2.04. Some difference is also noticed in Ti/V between the diorite and the granite ( 52.6- 54.2 for the former and 52.6- 54.2 for the latter). As compared with ocean ridge granites, both diorite and granite are characterized by remarkable LILE enrichment, as well as by moderate negative Ba and postive Ce anomalies. The contents of Nb and Ta in the diorite and granite are equivalent to those of the ocean ridge granites, but the contents of Zr, Hf, Sm, Y, and Yb are all lower than those of the ocean ridge granites, indicating that these granites are similar to the island-arc granites of Chile. From their geochemical characteristics, it is considered that the intrusive rocks in the area studied were formed in an island-arc environment at the continental margin. 展开更多
关键词 花岗岩 塔里木盆地 地球化学 岛弧环境
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海塔油田复杂断块井震断层解释关键技术及其应用
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作者 沙宗伦 陈国飞 +3 位作者 张飞飞 杜先芳 沈中梅 麻永明 《大庆石油地质与开发》 北大核心 2025年第5期70-80,共11页
海塔油田进入高含水开发阶段后,挖潜断控区剩余油对断层刻画成果的精度要求高,生产井已证实初期阶段断层识别与刻画精度难以满足需求。为解决上述问题,从地震解释性处理、多融合属性和断层解释思想研究入手,发展谱反演解释性处理技术,... 海塔油田进入高含水开发阶段后,挖潜断控区剩余油对断层刻画成果的精度要求高,生产井已证实初期阶段断层识别与刻画精度难以满足需求。为解决上述问题,从地震解释性处理、多融合属性和断层解释思想研究入手,发展谱反演解释性处理技术,提高低主频地震断层成像质量;创新HIS(色度−亮度−饱和度)融合属性技术,提高破碎带和小断层识别能力;形成以分期解释思想为指导的井震结合断层解释方法,解决了多期断层交切部位“切轴”问题,精细刻画断面形态。结果表明:综合运用上述技术可以有效识别出断距大于(等于)10 m的断层,深化复杂断块断裂体系认识;断层再认识成果在塔木察格盆地19区块构造变化区未动型剩余油挖潜中得到应用,共部署井位15口,新增地质储量4.32×10^(6)t。研究成果可为海塔油田整体断控区挖潜提供重要技术支撑。 展开更多
关键词 海塔油田 复杂断块 解释性处理 谱反演 HIS融合属性 断层分期解释
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苏北盆地复杂断块油藏CCUS-EOR关键技术与实践
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作者 姚红生 邱伟生 +3 位作者 周德华 钱洋慧 高和群 陈雨菡 《天然气工业》 北大核心 2025年第9期212-222,共11页
苏北盆地复杂断块油藏是中国东部断陷盆地油藏的典型代表,在该区开展CCUS-EOR技术攻关与工程实践,对中国CCUS产业的高质量发展具有重要的现实意义。为此,以苏北盆地复杂断块油藏为对象,针对“碎、低、薄、深、散”的油藏地质特征,以及C... 苏北盆地复杂断块油藏是中国东部断陷盆地油藏的典型代表,在该区开展CCUS-EOR技术攻关与工程实践,对中国CCUS产业的高质量发展具有重要的现实意义。为此,以苏北盆地复杂断块油藏为对象,针对“碎、低、薄、深、散”的油藏地质特征,以及CCUS应用中难以构建整体井网、无法规模化建设地面设施的难题,开展了油藏CCUS-EOR全流程技术攻关与矿场实践,构建了全流程技术体系,涵盖室内实验、油藏适应性评价、开发模式优化及配套工程等,并验证技术的可靠性与可行性。研究结果表明:①阐明了CO_(2)-水交替驱通过水相增阻和CO_(2)超覆作用实现了平面和纵向扩大波及范围、压驱+CO_(2)驱形成缝网增渗—高压建驱—扩散促吸—降黏混相等多维度增效机制的机理;②建立了“相态分析—驱替模拟—微观表征—机理揭示”的室内实验评价体系、含30项指标的CO_(2)驱油封存适应性评价体系,以及块状混相驱、大倾角重力稳定驱等4种开发模式;③研发形成了低成本捕集—输送—回注工艺和安全平稳注采工艺技术系列。结论认为,苏北盆地复杂断块油藏实践并形成的CCUS-EOR关键技术,可以为中国复杂断块油藏开展CCUS-EOR驱油封存实践提供关键技术支撑与重要示范参考。 展开更多
关键词 苏北盆地 复杂断块油藏 CCUS-EOR 油藏工程 碳捕集 关键技术 产出气回注
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苏北盆地中低TOC复杂断块页岩油勘探进展与攻关方向 被引量:7
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作者 钟志国 于雯泉 +1 位作者 段宏亮 杨保良 《油气藏评价与开发》 北大核心 2025年第1期11-18,共8页
苏北盆地页岩油资源潜力大,其中阜宁组二段(以下简称阜二段)和阜宁组四段(以下简称阜四段)页岩厚度大、分布面积广、脆性矿物含量高、纹层发育、有机质类型好,具有中低TOC(总有机碳含量)、构造岩性双复杂、断层/裂缝发育等典型地质特征... 苏北盆地页岩油资源潜力大,其中阜宁组二段(以下简称阜二段)和阜宁组四段(以下简称阜四段)页岩厚度大、分布面积广、脆性矿物含量高、纹层发育、有机质类型好,具有中低TOC(总有机碳含量)、构造岩性双复杂、断层/裂缝发育等典型地质特征,是勘探的主要目的层。2011年来,江苏油田通过加强基础研究和攻关实践,建立了中低TOC复杂断块页岩油差异富集理论,集成创新了勘探开发关键技术,探索了绿色低碳开发模式,取得高邮凹陷阜二段、阜四段页岩油勘探突破。但仍面临页岩油富集高产规律认识不清,工程工艺技术适配性待提升,效益开发技术政策不明确,开发成本较高等挑战。深化页岩油富集高产主控因素等基础研究,持续攻关迭代关键技术,优化一体化组织管理运行机制,最大限度提高优质储层钻遇率、页岩油储量动用程度和采收率,进一步降本增效,是实现页岩油规模建产与效益开发的主要途径。 展开更多
关键词 苏北盆地 高邮凹陷 复杂断块页岩油 勘探进展 攻关方向
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Mineral Chemistry and Geochemistry as Proxy for Petrogenetic Evaluation of Charnockites: Evidences from Marandahalli, Salem Block of Southern India
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作者 Sunki Amarendhar Valluri Sai Krishna Priya +1 位作者 Malintee Vittal Madabhhoshi Srinivas 《Open Journal of Geology》 CAS 2024年第11期963-987,共25页
The charnockites of Marandahalli, Dharmapuri District, Tamil Nadu India, form a part of the southern granulitic terrain in the Salem Block (SB). The charnockites are medium to coarse grained, inequigranular, with porp... The charnockites of Marandahalli, Dharmapuri District, Tamil Nadu India, form a part of the southern granulitic terrain in the Salem Block (SB). The charnockites are medium to coarse grained, inequigranular, with porphyroblastic and granophyric textures. They are composed of plagioclase feldspars (49 - 66 vol.%), K-feldspar (1 - 5 vol.%) and quartz (21 - 34 vol.%). The mafic minerals include pyroxene (2 - 7 vol.%) and biotite (1 - 12 vol.%). The accessory minerals include magnetite and apatite. Orthopyroxene compositions (MgO 16 - 22 wt.%) fall within the hypersthene series (En55.03Fs43.57Wo1.4) and yield peak metamorphic temperatures of 800˚C - 1000˚C. Biotites show K2O, MgO, FeO, TiO2, and Al2O3 concentrations consistent with magmatic formation, and Ti-in-biotite thermometry suggests temperatures of ~740˚C - 800˚C. Plagioclase compositions (An26-33) plot in the oligoclase field, while K-feldspar (Or93-99) plots in the orthoclase/microcline field. A ternary feldspar geothermometer indicates a retrograde temperature of 2 (65 - 68 wt.%), Na2O > K2O, high CaO (3 - 5 wt.%), MgO (2.5 - 4 wt.%) and Fe2O3 (2 - 6 wt.%). The concentration of V, Rb and Ni, and LREE-rich and HREE-depleted patterns of the rocks indicate low degree of partial melting. 展开更多
关键词 CHARNOCKITE Salem block Fractional Crystallization AMPHIBOLITE Marandahalli Peninsular Gneissic complex (PGC)
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A low-complexity line-based motion estimation algorithm and its hardware architecture
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作者 Li Wern CHEW Li-Minn ANG Kah Phooi SENG 《通讯和计算机(中英文版)》 2008年第9期1-4,共4页
关键词 复杂系统 计算机技术 硬件 计算方法
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基于优化VMD-DTCWT的局放信号去噪方法
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作者 伍忠东 王鹏波 +2 位作者 汤春阳 郑礼 苟敬聪 《兰州交通大学学报》 2025年第5期42-49,57,共9页
变压器局部放电检测是评估绝缘状态和预防故障的重要手段,但现场采集的变压器局部放电信号易受到背景噪声影响,需要通过去噪处理获取纯净信号。为此,提出一种基于改进VMD-DTCWT的局放信号去噪的方法。该方法基于峭度值准则采用改进的VM... 变压器局部放电检测是评估绝缘状态和预防故障的重要手段,但现场采集的变压器局部放电信号易受到背景噪声影响,需要通过去噪处理获取纯净信号。为此,提出一种基于改进VMD-DTCWT的局放信号去噪的方法。该方法基于峭度值准则采用改进的VMD算法初步去除了背景噪声中的窄带干扰噪声,其次通过使用美洲狮算法优化块阈值参数,进行双树复小波块阈值去噪,有效抑制白噪声干扰信号,最后使用自适应滤波器对背景噪声中的残余窄带干扰噪声进行滤除。实验结果表明,与传统去噪算法相比,提出的方法可以更有效地抑制噪声,使波形相似度系数在去除噪声后提高3%左右,更好地保留了局部放电信号的波形特征。 展开更多
关键词 局部放电 VMD 双树复小波 美洲狮算法 阈值块
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扬子北缘后河杂岩花岗岩类及其对古元古代造山作用的响应 被引量:1
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作者 李霄琦 赵燕 +3 位作者 张瑞英 敖文昊 兰彩云 李超 《岩石矿物学杂志》 北大核心 2025年第1期24-50,共27页
后河杂岩作为扬子北缘早前寒武纪基底岩石的重要组成部分,其岩石成因和构造背景尚不清楚,进而制约了对扬子北缘乃至整个扬子地块在古元古代时期的地质演化过程的理解。本文选取碑坝地区后河杂岩中的奥长花岗岩和二长花岗岩为研究对象,... 后河杂岩作为扬子北缘早前寒武纪基底岩石的重要组成部分,其岩石成因和构造背景尚不清楚,进而制约了对扬子北缘乃至整个扬子地块在古元古代时期的地质演化过程的理解。本文选取碑坝地区后河杂岩中的奥长花岗岩和二长花岗岩为研究对象,开展全岩主量、微量元素和Sm-Nd同位素、锆石U-Pb年代学及Lu-Hf同位素综合研究。U-Pb测年结果表明奥长花岗岩和二长花岗岩均形成于古元古代晚期,二者的结晶年龄分别为2101±10 Ma和2072±15 Ma。全岩主量、微量元素分析结果显示,奥长花岗岩具有高硅、富钠、低钾、贫镁的特征,属于准铝质-弱过铝质钙碱性Ⅰ型花岗质岩石系列,且显示岛弧花岗岩的特征;锆石εHf(t)值为-0.8~+4.6,全岩εNd(t)值为+0.1~+1.1,两阶段Hf模式年龄(t_(DM2))为3005~2469 Ma。与奥长花岗岩相比,二长花岗岩具有相对较低的硅含量,但是相对富镁、铝和钾,属于弱过铝质的高钾钙碱性Ⅰ型花岗岩。其稀土元素总量较高,轻、重稀土元素之间分异明显,伴随弱负Eu异常,并富集Rb、Ba、Th等大离子亲石元素,相对亏损Nb、Ta、Ti等高场强元素,亦具有岛弧花岗岩的特征。此外,该岩石具有较高的Mg^(#)值以及Cr和Ni含量,锆石εHf(t)值为-2.9~+2.4,全岩εNd(t)值为+0.1~+0.9,两阶段Hf模式年龄(t_(DM2))为2939~2604 Ma。根据上述特征,推测奥长花岗岩主要是由新太古代玄武质大陆下地壳部分熔融形成的,其形成过程中经历了一定程度的分离结晶作用,而二长花岗岩是幔源岩浆底侵并导致新太古代古老大陆地壳部分熔融形成的,其中有岩石圈地幔物质的添加。结合扬子北缘已报道的古元古代晚期(2.1~2.0 Ga)镁铁质-长英质岩浆活动的时空分布和岩石成因,推测扬子北缘碑坝地区后河杂岩中2101~2072 Ma的花岗质岩石形成于活动陆缘弧环境,是扬子北缘对全球古元古代哥伦比亚超大陆聚合过程的响应。 展开更多
关键词 扬子北缘 后河杂岩 古元古代 花岗质岩石 活动陆缘弧
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