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南海构造格局及其演化 被引量:59
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作者 张功成 贾庆军 +6 位作者 王万银 王璞珺 赵庆乐 孙晓猛 谢晓军 赵钊 唐武 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2018年第10期4194-4215,共22页
依据重磁资料在南海及其邻区识别出17条深大断裂和10个重磁异常区.据此并结合其他地质资料,在南海及其邻区划分出7个地质结构不同的构造单元.早白垩世南海地区曾形成过统一的基底,新生代时统一的南海基底发生肢解,这一个肢解过程经历了... 依据重磁资料在南海及其邻区识别出17条深大断裂和10个重磁异常区.据此并结合其他地质资料,在南海及其邻区划分出7个地质结构不同的构造单元.早白垩世南海地区曾形成过统一的基底,新生代时统一的南海基底发生肢解,这一个肢解过程经历了两个在时空上接踵发生、交叠作用的构造事件.第一个构造事件为巽他地块与华夏古陆之间古南海的萎缩、闭合和地块碰撞;第二个构造事件为南沙地块裂离华夏古陆并向巽他地块增生,且伴随新南海的持续扩张,直至中中新世.区域构造演化控制了南海沉积盆地呈"北三南三、东西两竖"格局分布,进而控制了油气富集区的分布. 展开更多
关键词 深大断裂 构造地层组合 地块 古地磁 油气 南海
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美松永久根管充填糊剂在一次性根管治疗中的疗效 被引量:1
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作者 赵庆乐 乔颖 何彦平 《检验医学与临床》 CAS 2018年第7期897-899,902,共4页
目的探讨美松永久根管充填糊剂在一次性根管治疗中的疗效。方法选择2016年1-12月北京市昌平区南口医院接诊的100例慢性根尖周炎(CAP)患者,共100颗患牙,按随机数字表法分为观察组和对照组,每例患者只取1颗患牙,每组各50颗患牙。两组均行... 目的探讨美松永久根管充填糊剂在一次性根管治疗中的疗效。方法选择2016年1-12月北京市昌平区南口医院接诊的100例慢性根尖周炎(CAP)患者,共100颗患牙,按随机数字表法分为观察组和对照组,每例患者只取1颗患牙,每组各50颗患牙。两组均行一次性根管治疗,观察组采用美松永久根管充填糊剂,对照组采用常规根管充填糊剂。比较两组治疗1周后疼痛感、牙周袋深度(PD)、牙龈指数(GI)、龈沟出血指数(SBI)及愈合情况。结果治疗后,观察组疼痛感发生率低于对照组,差异有统计学意义(P<0.05);两组PD、GI、SBI水平较治疗前均有所降低,且观察组PD、GI、SBI水平均低于对照组,差异均有统计学意义(P<0.05);观察组愈合总有效率高于对照组,差异有统计学意义(P<0.05)。结论在一次性根管治疗中采用美松永久根管充填糊剂对CAP进行治疗,效果确切,可有效减轻治疗后疼痛感,远期愈合效果明显。美松永久根管充填糊剂是目前治疗根尖周炎的理想根充材料,值得临床推广应用。 展开更多
关键词 美松永久根管充填糊剂 一次性根管治疗 根尖周炎 疗效
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Paleozoic Tectono-Metallogeny in the Tianshan-Altay Region,Central Asia 被引量:6
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作者 WAN Tianfeng zhao qingle WANG Qianqian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第4期1120-1132,共13页
The research on Paleozoic tectonics and endogenic metallogeny in the Tianshan-Altay region of Central Asia is an important and significant project. The Altay region, as a collision zone of the Early Paleozoic (500-39... The research on Paleozoic tectonics and endogenic metallogeny in the Tianshan-Altay region of Central Asia is an important and significant project. The Altay region, as a collision zone of the Early Paleozoic (500-397 Ma), and the Tianshan region, as a collision zone of the early period in the Late Paleozoic (Late Devonian-Early Carboniferous, 385-323 Ma), are all the result of nearly N-S trending shortening and collision (according to recent magnetic orientation). In the Late Devonian-Early Carboniferous period (385-323 Ma), regional NW trending faults displayed features of dextral strike-slip motion in the Altay and Junggar regions. In the Tianshan region, nearly EW-trending regional faults are motions of the thrusts. However, in the Late Carboniferous-Early Permian period (323-260 Ma), influenced by the long-distance effect induced from the Ural collision zone, those areas suffered weaker eastward compression, the existing NW trending faults converted into sinistral strike-slip in the Altay and Junggar regions, and the existing nearly E-W trending faults transferred into dextral strike-slip faults in the Tianshan region. The Rocks of those regions in the Late Carboniferous-Early Permian period (323-260 Ma) were moderately ruptured to a certain tension-shear, and thus formed a number of world famous giant endogenic metal ore deposits in the Tianshan-Altay region. As to the Central Asian continent, the most powerful collision period may not coincide with the most favorable endogenic metallogenic period. It should be treated to "the orogenic metallogeny hypothesis" with caution in that region. 展开更多
关键词 tectonics endogenic metallogeny long distance effect Tianshan-Altay region
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The genesis of tectono-magmatism in eastern China 被引量:15
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作者 WAN TianFeng zhao qingle 《Science China Earth Sciences》 SCIE EI CAS 2012年第3期347-354,共8页
The tectono-magmatism in eastern China is a hotspot for the researches, and many hypotheses of that were discussed. There is a middle crust with solid, low velocity and high conductivity in eastern China, which is imp... The tectono-magmatism in eastern China is a hotspot for the researches, and many hypotheses of that were discussed. There is a middle crust with solid, low velocity and high conductivity in eastern China, which is impossible to form"convection magmatic layer". The subduction and compression of oceanic plate induced to the lateral pressure for the eastern China lithosphere in the condition of increasing pressure and decreasing temperature, it is also impossible to form an extensively melting magma layer. In South China, the granitic zone migrates from west to east, their evolution cannot be explained by plate subduction. The original magmatic reservoirs are controlled by main faults and spheres, which occurred the tectonic detachment and formed in the process of decreasing pressure and increasing temperature. The magma only originates in very small part of lithosphere. The tectono-magmatism and tectonic detachment of eastern China lithosphere during the Jurassic and the Cretaceous are concentrate mainly near the intersections between the regional faults and middle crust or the Moho discontinuity, and then magma intrudes or erupts along faults. The tectono-magmatism of Cenozoic originates near the intersections between the regional high-angle normal faults and the bottom of lithosphere. Obviously, the different penetration depth of faults induces a different kind of magmatism. 展开更多
关键词 TECTONO-MAGMATISM GENESIS migration of magmatic zone tectonic detachment decreasing pressure and increasingtemperature
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Early diagenetic growth of carbonate concretions in the upper Doushantuo Formation in South China and their significance for the assessment of hydrocarbon source rock 被引量:6
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作者 DONG Jin ZHANG ShiHong +4 位作者 JIANG GanQing zhao qingle LI HaiYan SHI XiaoYing LIU JunLai 《Science China Earth Sciences》 SCIE EI CAS 2008年第9期1330-1339,共10页
Mineralogical and textural characteristics and organic carbon composition of the carbonate concretions from the upper Doushantuo Formation (ca. 551 Ma) in the eastern Yangtze Gorge area reveal their early diagenetic (... Mineralogical and textural characteristics and organic carbon composition of the carbonate concretions from the upper Doushantuo Formation (ca. 551 Ma) in the eastern Yangtze Gorge area reveal their early diagenetic (shallow) growth in organic-rich shale. High organic carbon content (up to 10%) and abundance of framboidal pyrites in the hosting shale suggest an anoxic or euxinic depositional environment. Well-preserved cardhouse clay fabrics in the concretions suggest their formation at 0-3 m burial depth, likely associated with microbial decomposition of organic matter and anaerobic oxidation of methane. Gases through decomposition of organic matter and/or from methanogenesis created bubbles and cavities, and anaerobic methane oxidation at the sulfate reduction zone resulted in carbonate precipitation, filling in bubbles and cavities to form spherical structures of the concretions. Rock pyrolysis analyses show that the carbonate concretions have lower total organic carbon (TOC) content but higher effective carbon than those in the host rocks. This may be caused by enclosed organic matter in pores of the concretions so that organic matter was protected from further modification during deep burial and maintained high hydrocarbon generating potential even in over-matured source rock. As a microbialite sensu latu, concretions have special growth conditions and may provide important information on the microbial activities in depositional and early burial environments. 展开更多
关键词 Doushantuo Formation CARBONATE CONCRETION SEDIMENTARY environment HYDROCARBON source rock
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