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《吉林大学学报(地球科学版)》2015,(Z1)
<正>研究目的:通过分段加热模拟实验,了解与致密砂岩共存的方解石样品在形成过程中吸附烃类的经历,以便进一步追溯和研究样品的地质背景。样品背景:方解石样品5个(60~80目),采自漠河盆地泥盆系5个不同层位。实验条件:气相色谱-单体碳同位素质谱联用仪(GC/C/delta Plux XP)是德国Thermo Finnigan公司生产的新型仪器。气相色谱条件:HP-5石英毛细管色谱柱(60 m×0.32 mm×0.25μm),升温程序:80℃恒温5 min,以3℃/min程序升温至300℃,恒温30 min;载气高纯He,碳同位素比值经PDB标准换算。 相似文献
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LA-MC-ICP-MS锆石Hf同位素的分析方法及地质应用 总被引：68，自引：111，他引：68
本研究利用Thermo Finngan Neptune型多接收等离子质谱和Newwave UP213 激光剥蚀系统对两个国际锆石标准和一个实验室锆石标准进行了系统的测定.测得的TEMORA、GJ1和FM02锆石标准的176Hf/177Hf比值分别为0.282700±64(2SD,N=22),0.282008±25(2SD,N=26)和0.282967±44(2SD,N=27),该结果在误差范围内与文献报道值完全一致.采用不同的剥蚀直径对FM02锆石标准进行了对比测定,结果在误差范围内是一致的.从分析结果来看,GJ1和FM02的Hf同位素比值变化范围较小,是Hf同位素LA-MC-ICP-MS测试的理想标准锆石.文中还对四个不同地区的锆石Hf同位素进行了测定,结合前人研究,对其成因和物质来源进行了初步探讨. 相似文献
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《地质通报》2014,(10)
正国外总发行:中国国际圈书贸易总公司(地址:北京399号信箱邮编:100044国外发行代号:M3684)《地质通报》是中国国土资源部主管、中国地质调查局主办的地质学综合性学术刊物,本刊遵循"百花齐放,百家争鸣"的方针,以推动地质调查与地质科技创新发展.为国民经济建设和社会公众服务为宗旨,力求全面展示和及时报道国家地质调查全新领域的新进展、新成果、新发现、新方法。辟有"专题报告"、"基础地质"、"矿产资源"、"水文地质·环境地质","疗法与应用"、"快报"、"学术讨论"、"特稿·专论"、"综述与进展"、"地学纵横"、"知识经纬"、"动态与信息"、"书评"等栏日,内容涉及基础地质、经济地质、海洋地质、能源地质、生态环境地质、灾害地质、城市地质、农业地质、地质遗迹(公园)、勘查地球物理、勘查地球化学、地质实验、探测技术、地质调查 相似文献
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《地质通报》2014,(11)
正《地质通报》——全方位展示中国地质调查研究科技信息的重要窗口及时了解中国地质调查研究进展与成果的必备手册国内总发行:北京市报刊发行局邮发代号:2-767国外总发行:中国国际图书贸易总公司发行代号:M3684《地质通报》是中国国土资源部主管、中国地质调查局主办的地质学综合性学术刊物。本刊遵循"百花齐放,百家争鸣"的方针,以推动地质调查与地质科技创新发展,为国民经济建设和社会公众服务为宗旨,力求全面展示和及时报道国家地质调查全新领域的新进展、新成果、新发现、新方法。辟有"专题报告"、"基础地质"、"矿产资源"、"水文地质·环境地质"、"方法与应用"、"快报"、"学术讨论"、"特稿·专论"、"综述与进展"、"地学纵横"、"知识经纬"、"动态与信息"、"书评"等栏目,内容涉及基础地质、经济地质、海洋地质、 相似文献
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笔者等以近20年CNKI数据库收录的核心期刊中关于"地质公园"和"地质遗迹"主题的论文为研究对象,应用文献计量学方法开展地质公园领域论文数量、期刊、主要作者、关键词、主要机构的综述研究。采用CiteSpace软件进行关键词共现、聚类分析、关键词时区视图等可视化操作,根据聚类结果将地质公园领域的研究热点归纳为:"地质公园规划"、"地质遗迹保护"、"遗迹资源研究"、"地质公园旅游"、"可持续发展"5个方面,通过关键词梳理将地质公园研究阶段划分为:"规划建设期"、"深入完善期"和"市场开发期"。最后,通过对各热点及相关作者研究的总结,提出"体验优化研究"、"相关理论建设"和"多元化景观系统"3个潜在热点方向。 相似文献
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《地质通报》2014,(10)
正《地质通报》——全方位展示中国地质调查研究科技信息的重要窗口及时了解中国地质调查研究进展与成果的必备手册国内总发行:北京市报刊发行局邮发代号:2-767国外总发行:中国国际图书贸易总公司发行代号:M3684《地质通报》是中国国土资源主管、中国地质调查局主办的地质学综合性学术刊物。本刊遵循"百花齐放,百家争鸣"的方针,以推动地质调查与地质科技创新发展,为同民经济建设和社会公众服务为宗旨,力求全面展示和及时报道同家地质调查全新领域的新进展、新成果、新发现、新方法。辟有"专题报告"、"基础地质"、"矿产资源"、"水文地质·环境地质"、"方法与应用"、"快报"、"学术讨论"、"特稿·专论"、"综述与进展"、"地学纵横"、"知识经纬"、"动态与信息"、"书评"等栏目,内容涉及基础地质、经济地质、海洋地质、能源地质、生态环境地质、灾害地质、城市地质、农业地质、勘查地球物理、勘察地球化学, 相似文献
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《地质通报》2014,(7)
正《地质通报》——全方位展示中国地质调查研究科技信息的重要窗口及时了解中国地质调查研究进展与成果的必备手册国内总发行:北京市报刊发行局邮发代号:2-767国外总发行:中国国际图书贸易总公司发行代号:M3684《地质通报》是中国国土资源部主管、中国地质调查局主办的地质学综合性学术刊物。本刊遵循"百花齐放,百家争鸣"的方针,以推动地质调查与地质科技创新发展,为国民经济建设和社会公众服务为宗旨,力求全面展示和及时报道国家地质调查全新领域的新进展、新成果、新发现、新方法。辟有"专题报告"、"基础地质"、"矿产资源"、"水文地质·环境地质"、"方法与应用"、"快报"、"学术讨论"、"特稿·专论"、"综述与进展"、"地学纵 相似文献
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《地质通报》2014,(6)
正国外总发行:中国国际图书贸易总公司(地址:北京399号信箱邮编:100044国外发行代号:M3684)《地质通报》是中国国土资源部主管、中国地质调查局主办的地质学综合性学术物。本刊遵循"百花齐放,百家争鸣"的方针,以推动地质调查与地质科技创新发,为国民经济建设和社会公众服务为宗旨,力求全面展示和及时报道国家地质调全新领域的新进展、新成果、新发现、新方法。辟有"专题报告"、"基础地质"、"矿资源"、"水文地质·环境地质"、"方法与应用"、"快报"、"学术讨论"、"特稿·专论"、综述与进展"、"地学纵横"、"知识经纬"、"动态与信息"、"书评"等栏目,内容涉及基地质、经济地质、海洋地质、能源地质、生态环境地质、灾害地质、城市地质、农业地地质遗迹(公园)、勘查地球物理、勘查地球化学、地质实验、探测技术、地质调查息技术、科技政策、科技管理等专业领域。作为中国地学传媒中的首份地质学综 相似文献
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After the fall of the Mengistu regime in 1991 the extreme south of Ethiopia first went through a period of relative peace in spite, or because of, the total absence of state institutions. The structures of local societies, among them thegada or generation set system, and the local forms of food production appeared to be sufficient for the needs of the local population. Then a variety of parties and liberation fronts started to compete for the control of state institutions which were expected to reappear. This led to a local war in which group identities were re-drawn to fit the patterns of ethnic movements or micro nationalisms. The paper examines primarily the examples of Oromo and Somali identity in this context. 相似文献
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Makhnach A. A. Kuleshov V. N. Pokrovskii B. G. Gulis L. F. Mikhailov N. D. Kolosov I. L. 《Lithology and Mineral Resources》2002,37(6):536-545
The isotopic composition of oxygen and carbon was studied in accessory carbonates and quartz separated from salts in Upper Devonian halogenous formations of the Pripyat Trough (Belorus). It is established that isotopic characteristics vary in a wide range. Values of 18O vary in the following range (SMOW): from 18.2 to 29.2 in calcites, from 15.7 to 32.5 in dolomites, and from 17.4 to 27.2 in quartz. Values of 13C range from –13.4 to 1.4 in calcites and from –11.1 to 1.7 in dolomites (PDB). Results obtained indicate highly variable isotope-geochemical conditions of sedimentation and early diagenesis during the formation of evaporitic sediments. Accessory minerals were repeatedly formed in a wide temperature range and probably at various stages of the lithogenesis. 相似文献
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Akira Miyake 《Contributions to Mineralogy and Petrology》1990,104(4):390-396
Dendritic cordierite occurs in argillaceous hornfels from the Toki area, Gifu Prefecture, Japan. The cordierite crystal consists of c-arms elongated parallel to the c-axes and a-arms perpendicular to the c-axis. The latter arms could be divided into six kinds of untwinned a-arms with different growth directions elongated parallel to the respective a-axis and twinned a-arms elongated parallel to the (110) twin plane. A-arms branch out from c-arms or other a-arms with different growth directions and c-arms sometimes branch out from a-arms, leading to a tree-like structure. Each of the c-arms contains three kinds of domains related by a three-fold axis about the c-axis. These domains are irregularly distributed without any relation to the shape of the c-arm and the domain boundaries are of zigzag shape. This domain arrangement suggests that c-arms grew as hexagonal cordierite and were later transformed into orthorhombic cordierite. The fact that each untwinned a-arm has a fixed growth direction to its orientation suggests that the a-arms grew as an orthorhombic cordierite. From the growth directions of c- and a-arms, orthorhombic and hexagonal phases are considered to grow preferentially along the c- and a-axes, respectively. The branching of a new arm is explained by nucleation on an old arm with a different preferred growth direction. The preferential growth is discussed in terms of a significant chemical potential gradient of the cordierite component. This has been preserved in the mineral zoning observed in the matrix around the cordierite porphyroblast. 相似文献
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Land subsidence, a major and well-known geological hazard in Shanghai, has caused serious losses. Based on past studies, the cost and benefit of the Shanghai's land subsidence hazard control were assessed and forecasted by risk assessment. An economic benefit-risk assessment was taken in order to control completely land subsidence and make rational safety elevations of the flood control wall. The result of risk assessment shows that the present 6.9-m elevation of the floodwall is not sufficient for the standard of occurring only once in a thousand years. After 200 years, the spring tide hazardous risk losses caused by land subsidence would amount to 49.73 million yuan per year. The proportion of expense in thoroughly controlling land subsidence to the economic benefit is 1:41.44; to construct the flood control wall to an elevation that would prevent inundation from a flood event, to reach the standard of occurring only once in a thousand years, and to avoid tide losses, the ratio of the investment of reducing tide hazard to the economic benefit should be 1:53.24. 相似文献
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The abiotic, thermochemically controlled reduction of sulfate to hydrogen sulfide coupled with the oxidation of hydrocarbons, is termed thermochemical sulfate reduction (TSR), and is an important alteration process that affects petroleum accumulations in nature. Although TSR is commonly observed in high-temperature carbonate reservoirs, it has proven difficult to simulate in the laboratory under conditions resembling nature. The present study was designed to evaluate the relative reactivities of various sulfate species in order to provide greater insight into the mechanism of TSR and potentially to fill the gap between laboratory experimental data and geological observations. Accordingly, quantum mechanics density functional theory (DFT) was used to determine the activation energy required to reach a potential transition state for various aqueous systems involving simple hydrocarbons and different sulfate species. The entire reaction process that results in the reduction of sulfate to sulfide is far too complex to be modeled entirely; therefore, we examined what is believed to be the rate limiting step, namely, the reduction of sulfate S(VI) to sulfite S(IV). The results of the study show that water-solvated sulfate anions are very stable due to their symmetrical molecular structure and spherical electronic distributions. Consequently, in the absence of catalysis, the reactivity of is expected to be extremely low. However, both the protonation of sulfate to form bisulfate anions () and the formation of metal-sulfate contact ion-pairs could effectively destabilize the sulfate molecular structure, thereby making it more reactive.Previous reports of experimental simulations of TSR generally have involved the use of acidic solutions that contain elevated concentrations of relative to . However, in formation waters typically encountered in petroleum reservoirs, the concentration of is likely to be significantly lower than the levels used in the laboratory, with most of the dissolved sulfate occurring as , aqueous calcium sulfate ([CaSO4](aq)), and aqueous magnesium sulfate ([MgSO4](aq)). Our calculations indicate that TSR reactions that occur in natural environments are most likely to involve bisulfate ions () and/or magnesium sulfate contact ion-pairs ([MgSO4]CIP) rather than ‘free’ sulfate ions () or solvated sulfate ion-pairs, and that water chemistry likely plays a significant role in controlling the rate of TSR. 相似文献
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基于地下水开发的岩溶地下水系统类型划分方案探讨 总被引：3，自引：2，他引：1
岩溶山区多年的地下水开发利用实践证明,传统的岩溶地下水系统划分不利于指导岩溶山区勘查找水和地下水资源的开发。为了更好地指导岩溶山区地下水资源的勘查和开发,文章从有利指导岩溶山区地下水勘查和开发利用的角度,在继承传统划分方法的基础上,提出了一种新的以地下水的赋存条件、富集条件,以及开发条件三个层次组合的地下水系统综合划分方法:根据岩溶地下水系统与供水目标在空间上的关系划分为“高位”和“低位”两种类型,根据控制地下水富集的水文地质结构划分为“开放”和“封闭”两个亚类,根据地下水的水动力和排泄特点划分为集中（地下河、岩溶泉）和分散排泄三类系统,并给出了“高位”型地下水系统开发成本低、“封闭型”地下水系统资源丰富,“封闭型地下水系统”是缺水区勘查找水的主要目标,合理的岩溶水系统的开发利用应按照“高位封闭型”、“高位开放型”、“低位封闭型”的顺序进行规划部署,“低位开放型”地下水系统则因富水性差、开发利用成本高可作为储备水源地的建议。 相似文献
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本文讨论了“拉疏隆起－压缩凹陷”－不稳定孕震体特性和形成机理,通过对丽江７．０级地震前滇西地区的地壳形变资料,进一步证实本区有强震发生及发震的地点;讨论了孕震体由“僵硬闭锁”到“不同步加速”,“分离反向”“不均匀掀斜”再度“停滞平衡”甚至“颤抖”等多态不稳变化,是地壳形变的短临地震前兆特征; 相似文献
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Eugene J. Palka 《GeoJournal》1995,37(2):201-208
This paper revisits and interrelates the scope of military geography and the changing role of the military, two themes previously addressed in the 1993 and 1994 special editions ofGeoJournal. I begin by tracing the evolution of military geography in the US from World War I through the end of the Gulf War to reveal the demise of the subfield within American academic geography. Within the context of the post-Cold War era, I describe the military's reorientation and emphasize the need and opportunity to broaden the scope of military geography accordingly. The military's current operating environment is best characterized by operations other than war, undertaken on an unprecedented scale. Military geographers and regional, systematic, and technical experts throughout the discipline now have an unparalleled opportunity to contribute to the success of peacekeeping, humanitarian, and disaster assistance missions with which the military is currently preoccupied. Initiatives by academic geographers would not only enhance mission accomplishment from the military and federal government's perspective, but might also help to revive military geography as a legitimate subfield by demonstrating that military geographic endeavors can be both socially responsible and politically correct, particularly within operations other than war. 相似文献
19.
Defining the urban 总被引：1，自引：0，他引：1
A. Sayer Dr. 《GeoJournal》1984,9(3):279-284
In everyday discourse, the term urban causes few problems, but it certainly has for social theory. While the paper accepts the recent consensus that the term no longer serves to refer to a distinct object in capatalist societies, it argues that the familiar arguments have been confused by inadequate approaches to the problem of definition and inadequate concepts of space and ideology. Clarification of such definitions is a prime task of social theory and different methods of definition are discussed. The paper ends with a commentary on what is probably the best attempt at defining the urban — Raymond Williams The Country and the City. 相似文献
20.
Olivines which cool under oxidizing conditions exsolve iron oxides at high temperature, and at low temperatures break down to essentially chloritic materials. Olivines which cool under non-oxidizing conditions alter at intermediate temperatures to complex assemblages of chlorite and interstratified phyllosilicates containing a smectite. Alteration under oxidizing conditions at low temperature, probably below 140° C, produces iddingsite, an orientated assemblage of goethite and interstratified phyllosilicates also containing a smectite.Post-deuteric alteration extends or initiates the breakdown of olivine to phyllosilicate mixtures often resulting in widespread movement of materials through the flow. Post-deuteric alteration of iddingsite produces strongly pleochroic, highly ordered varieties which eventually break down to green phyllosilicate assemblages.Weathering of olivine may produce orientated assemblages similar to deuteric forms of iddingsite. Weathering of green alteration products results in oxidation and the liberation of discrete iron hydroxides.Alteration in all cases requires exchange of material between interstitial components and olivine. During deuteric alteration, plagioclase and pyroxene are usually unaffected. 相似文献