萃取分离—石墨炉原子吸收光谱法测定铅锌矿中的铟

样品经硝酸、氢氟酸分解除硅,加热硫酸冒烟除尽硝酸、氢氟酸,利用铟与氢溴酸能生成稳定的络合物并被乙酸丁酯萃取的性质,将铟与其它干扰离子分离并富集.使用MOLAARM6（Thermo Electron Corporation）石墨炉原子吸收分光光度计,以钒为机体改进剂,测定铅锌矿中的铟.方法检出限为LD=0.012ug/ml.实验结果令人满意.     

岩石样品分步热解-质谱在线分析释气量对比研究

<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。     

LA-MC-ICP-MS锆石Hf同位素的分析方法及地质应用

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.     

《地质通报》——全方位展示中国地质调查科技信息的重要窗口及时了解中国地质调查与研究最新成果的必备读物

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     

欢迎订阅《地质通报》(月刊)

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、     

国内地质公园研究演化趋势与热点分析——基于知识图谱视角

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。     

《地质通报》——全方位展示中国地质调查科技信息的重要窗口及时了解中国地质调查与研究最新成果的必备读物

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"、     

欢迎订阅《地质通报》(月刊)

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,     

欢迎订阅《地质通报》(月刊)

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     

《地质通报》——全方位展示中国地质调查科技信息的重要窗口及时了解中国地质调查与研究最新成果的必备读物

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     

Dendritic cordierite in argillaceous hornfels from the Toki area,Gifu Prefecture,central Japan

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.     

Local war and its impact on ethnic and religious identification in Southern Ethiopia

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.     

地学时间单位Ma和Myr及其派生单位用法的探讨

针对夏明生先生认为“Ma”及其派生单位(如“m/Ma”和“℃/Ma”)在地学期刊中属错误用法的观点,查阅了国家标准GB 3100-93和国际地学期刊有关规定。进而提出“Ma”和“Myr”均可表示“100万年”的观点,并指出这两个单位在国际期刊用法中的区别,即“Ma”用于表示某一地质事件距今的绝对年代(absolute dates),而“Myr”用于表示某一地质事件的延续时间或时间间隔(duration或interval)。另外,还提出了Ma”和“Myr”的派生单位供大家讨论。      

Isotopic Composition of Oxygen and Carbon and Formation Temperature of Accessory Minerals from Evaporitic Sediments in the Pripyat Trough

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.     

Oldest Atlantic seafloor

Basalt recovered beneath Jurassic sediments in the western Atlantic at Deep Sea Drilling Project sites 100 and 105 of leg 11 has petrographic features characteristic of water-quenched basalt extruded along modern ocean ridges. Site 100 basalt appears to represent two or three massive cooling units, and an extrusive emplacement is probable. Site 105 basalt is less altered and appears to be a compositionally homogeneous pillow lava sequence related to a single eruptive episode.Although the leg 11 basalts are much more closely related in time to the Triassic lavas and intrusives of eastern continental North America, their geochemical features are closely comparable to those of modern Mid-Atlantic Ridge basalts unrelated to postulated mantle plume activity. Projection of leg 11 sites back along accepted spreading flow lines to their presumed points of origin shows that these origins are also outside the influence of modern plume activity. Thus, these oldest Atlantic seafloor basalts provide no information on the time of initiation of these plumes. The Triassic continental diabases show north to south compositional variations in Rb, Ba, La, and Sr which lie within the range of plume-related basalt on the Mid-Atlantic Ridge (20 °–40 °N). This suggests that these diabases had mantle sources similar in composition to those beneath the present Mid-Atlantic Ridge. Plumes related to deep mantle sources may have contributed to the LIL-element enrichment in the Triassic diabase and may alos have been instrumental in initiating the rifting of the North Atlantic. Systematically high values for K and Sr⁸⁷/Sr⁸⁶ in the Triassic diabases may reflect superimposed effects of crustal contamination in the Triassic magmas.Contribution Number 3953 from the Woods Hole Oceanographic Institution     

Economic benefit risk assessment of controlling land subsidence in Shanghai

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.     

Evaluation of biotite-garnet geothermometers: application to the English River subprovince,Ontario

In recent years, there have been numerous calibrations of the biotite-garnet Fe-Mg exchange geothermometer. The Eastern Lac Seul region of the English River subprovince, Ontario, provides an excellent field area in which to compare these calibrations.Trend surface analysis using the temperatures obtained from garnet cores and matrix biotites-showed almost identical trends in the eastern Lac Seul region regardless of the calibration used. The absolute temperatures and the precision of each calibration do, however, show large variation. Geothermometers based solely on lnK_D were found to give more precise results than the calibrations that attempt to incorporate non-Fe-Mg components. The Perchuk and Lavrent'eva (1983) thermometer yields the most precise and accurate results. If a sufficient number of samples are collected over a region, it can be used to estimate metamorphic temperature trends to ±30° C. Metamorphism and migmatization of the English River subprovince occurred during the Kenoran orogeny, 2.68 b.y. ago. Our results show that a thermal anticline has been preserved, with temperatures of 600° C at the north and south contacts with Uchi and Wabigoon Greenstone belts, increasing to 725 °C at the center of the subprovince. A garnet-cordierite in isograd occurs at 650° C and an orthopyroxene in isogradat 700° C.     

Theoretical study on the reactivity of sulfate species with hydrocarbons

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.     

Space in geography

The concept of space is one of the most fundamental of geographical concepts. There is no work in geography that does not certain it. Nevertheless, geography has not as yet formulated an explicit and unambiguous definition of geographical space. This fact has had negative consequences for geographical theory, methodology and application. In the effort of contributing to its elimination we will try to outline the basic connotations of the concept.The concept of geographical space is a relational one. It acquires meaning and sense only when related to other concepts. The concept of space may be conceived as a supplement to things, i.e. substantively conceived objects. Space conceived in this way is the synonym of emptiness. The concept of space may be also conceived in relation ti individual landscape elements as their environments. Space conceived in this way has the character of a field of force. And, finally, space may be conceived also with respect to the totality of landscape elements, i.e. the system expressed by the term synergic. It is only this third variant of space which should be understood as the geographical space in the full menaing of the term. It is only this conception of geographical space as the space filled with qualities in relations and proportions that is considered as one of the basic prerequisites for the formulation of the theory of geography as science capable of prediction and thus also of practical utilization.