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20 0 0年 4月 2 0日 ,乌兹别克斯坦卡什卡达林斯克区的岳尔捷帕发生了 M=5.4级强烈地震。对这次地震前后 (1 999年 1 0月 3 1日— 2 0 0 0年 4月 2 2日 )的地震序列进行了初步分析 ,并结合震区附近的《舒尔奇》和《朱玛巴扎尔》等综合预报台地下水观测参数 (流量、湿度、Eh值、p H值等 )的变化和震源机制解 ,分析了应力场的变化和迁移特征。最后认为 k≤ 1 2的地震可以引起应力场的变化 ,这种变化可通过综合观测台来跟踪研究 ;观测点彼此间距不应超过1 0 0— 1 50 km;每个观测点必须选配自己的一组最有信息量的观测方法 相似文献
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土壤氡气异常特征与台湾南投7.6级地震 总被引：4，自引：0，他引：4
总结了10年来长乐筹东土壤氡气（土氡）观测点所测得的9个3．6级以上地震的土氡前兆异常特征，表明土氡异常具有预报意义。同时着重分析了1999年9月21日台湾南投Ms7.6级地震前该测点4－6月间的土氡异常特征，据此在1999年的半年度会商中提出预报意见。并介绍了7月后该测点的土氡变化特征，认为7－9月间测值的变化是由于降雨过多引起的。 相似文献
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长白山天池火山区上地壳Q值结构 总被引：4，自引：0，他引：4
同天然地震资料相比，人工地震剖面观测资料具有震源球对称且位置已知，观测点位密集、震源和观测点呈直线排列、速度结构已知等突出优点。本文提出了一种利用人工地震振幅资料反演分层介质中Q值的新方法。在利用该方法得到Q值深度函数的基础上，综合各炮点的结果，可研究Q值沿剖面的横向变化。利用上述方法计算了长白山L1剖面上地壳的Q值值结构。发现长白山天池火山区下方Q值明显低于邻近地区，该区域位于天池地区壳内低速异常体的上部，对应于已往的火山喷发通道。 相似文献
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汶川8.0级地震氡观测值震后效应特征初步分析 总被引：12，自引：0，他引：12
文中收集了2008年5月12日的四川汶川8.0级地震放射性同位素氡的观测资料, 初步分析了汶川地震氡观测值震后效应的特征。 结果表明, 氡震后效应的观测点大多沿着地震破裂带分布即在震源北侧的北东向与南侧的南北向, 变化以阶变上升型为主, 而且部分观测点发生了可能与氡射气浓度相关的水位或流量同步变化。 截止到2008年10月, 大部分产生震后效应的观测点已经恢复到原来测值状态, 但仍有少部分测点保持震后变化的的高值或低值, 甚至有的测点继续上升。 对氡震后效应的初步统计分析结果, 肯定了氡射气具有对地震波响应的特点, 也提出了研究地球化学组分变化与含水层动力过程的关系等问题, 这有利于氡的地震前兆机理的研究。 相似文献
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研究了1995年10月24日云南省武定6．5级强震前的地震活动性参数、空间分布图象、距震中135km的巧家台振幅比、波速比演化特征，结果表明武定6．5级地震孕育发生有明显的阶段性变化，经历了早期（1988年4月－1992年7月），中期（1992年8月－1995年3月），晚期（1995年4月－1995年10月）阶段的发展，最终发生了强震。最后应用岩石破裂实验结果，分析了武定6．5级地震孕震过程。 相似文献
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德令哈井水温异常特征与地震的关系 总被引：1，自引：0，他引：1
较为系统地分析了德令哈水温观测点自2008年以来的水温观测数据,发现这口井在2008年5月12日四川汶川Ms8．0级和2010年4月14日青海玉树Ms7．1级地震前均有较明显的前兆异常;2013年4月20日在同一井孔,同一深度架设了水温观测仪,对比观测资料显示,2套仪器观测资料形态一致,水温观测资料真实、可靠。 相似文献
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Реϑакцшонная Коллегия 《Studia Geophysica et Geodaetica》1968,12(2):235-236
12 января 1968 г. исполнилось 85 лет со дня рождения доктора техническиш наук, пофессора франтишека фиалы, выдающегося ученго-геодезиста и педагога, посвятившего свою плодоворную жизнь бекорыстному служению геодезической науке и высшей школе. жизнь юбиляра может служнть образцом трудолубия и беззаветной преданности делу, плодотворного сочетания наично-педагогической деятелвности с личным, творческим участием в фундаментальныш геодезическнх работах страны. Он оставил глубокий след прежде всего в области математической картографин, обогатив ее фундаментальными грудами, завершенными учебником “Математическая кчртография” (“Matematická kartcgrafie”, N?SAV, Praha 1955), переизданного на немецком языке (“Mathematische Kartographie”, VEB Vlg. Technik, Berlin 1957). Его призвание к математической картографии датируется уже его докторской диссертациеи, которую он защитил в 1911 г., по проблеме конформного отображения Гаусса земного сфероида на шаре, применительно к конкретным условиям страны (“Gaussovo konformní zobrazení sféroidu zemského na kouli se zvlá?tním z?etelem na země koruny ?eské”). В 1921 г. им была опубликована фундаменталыая работа дВыбор картографического графического изображения для чехословацкого государства с введением в картографию” (“Volba zobrazení pro stát ?eskoslovenský s úvodem do kartografie”, ?MT, Praha 1921), по которой ему было в 1922 г. присвоено звание доцента высшей геодезии. С 1927 г, когда он стал профессором мттематической геодезии и математической картогррфии Чешского политехнического институга в Праге, он посвятил себя, прежде всего, составлению учебных пособий по дисциплинам, которые за нимбыли закреплены. Эго перу принадлежит ?яд томов по матемчтической геодезии и математической картографии, которые переиздавались в несколько раз, будучи автором буквально постоянно усовершенствуемыми. Они стали не только блестящими пособиями студентов высшей школы, но также прекрасными руководствами и настольными посовиями геодезистов на прпизводстве и в научно-исследовательскиш инстигугах. Профессор фиала постоянно удепял большое внимание углублению и расширению геодезической специальности в Чешском политехническом институте в Праге. В несколько раз он был избран деканом геодезического факультета и этот период он посвятил расцвету факультета полностью. Кроме высшей школы профессор фиала активно участвовал в многих научныш и научно-обшественнын органах страны, прежде всего в Чехословчцком ноциональном комитете геодезии и геофизики ЧСАН, в научных советах научных учреждений страны по геодезии и картографии (Научно-qiсследовательского иистигуга геодезии, топографии и картографии и картографнческой лаборатории ЧСАН), в Центральном совете Центрального управления геодезии и картографии, в Обществе чехословацкнх математиков и физиков, в редакционных коллегиях геодезических журналов, и т. д. Признание научных, педагогических и обществениых заслуг профессора фиалы выражено в его награждении труда в 1963 г., по случаю его восьмидесяилетия. Питомцы профессора фиалы и все, кто с ним совместно работают и работаяи, знают его еще как исключительно скромного, отзывчивого и откровенного человека с большим и чутким сердцем, который всегда ставит пользу дела на первое место, не щадя своих сил, н который никогда не руководстуется узко лячными интересамх. Наш жырнал, отмечая 75-летие*) профессора, фиалы, принес уже его детальные биографические данные и детальное описание его плодотворной деятельности. По сличаю же 85-летия, которое, застало его совершенно крепким, принимающим актнвное участие в научных органах странах страны, нам хотелось бы от всей душн пожелатв нашему дорогому юбиляру впредь постоянно крепкого здоровья, чтобы он мог долгие годы продолжать свою деятельность и способствовать дальиейшему развитню чехословацкой геодезии. 相似文献
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HU Ping YIN Xiulan ZHAO Linghu & LI Dien . Department of Earth Sciences China University of Geosciences Wuhan China . Northeastern Illinois University Chicago IL USA . China Institute of Geo-Environmental Monitoring Beijing China . Division of Chemistry Los Alamos National Laboratory Los Alamos NM USA 《中国科学D辑(英文版)》2005,48(11)
A large amount of nuclear wastes has been pro-duced due to nuclear weapon development and nuclear electricity generation. One possible resolution for the disposal of the nuclear wastes is to seal them in an underground repository, which requires detailed knowledge on the mobility, chemical behavior and immobilization of radionuclides in underground water. In addition, toxic heavy metals are extensively present in ground and underground water, how to immobilize and remedy these toxic heavy meta… 相似文献
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公元849年10月20日(唐宣宗大中三年十月辛巳),在内蒙古包头附近发生了一次大地震，造成城堡、军营和民房破坏等严重震害和数千人死亡。目前对本次地震的震中位置、烈度和震级等基本参数认识尚存疑。通过对相关史料的系统梳理，重点对位置存疑的云伽关或云伽镇等进行进一步分析论证，重新核定了主要破坏地点及其地震烈度，修绘了地震等震线图，校核了地震震级、震中位置等基本参数。结果表明，公元849年地震等震线呈不对称的纺锤形，长轴方向为近东西向，短轴呈近南北向，极震区烈度可达X～X+度，震中位置大约在今内蒙古包头市附近，即40.6°N、110.3°E,震级达(7.8±0.3)级或7级。其中，等震线南侧地震影响范围大(包括河套盆地及其以南较大区域)、震害重、烈度衰减慢，而北侧几乎无震害记载，地震烈度衰减快，影响范围小。本次地震烈度等震线属于典型的正断层地震类型，其发震构造为大青山山前断裂中西段。文章依据历史地震史料校核结果与前人基于活动断裂研究结果所确定的震中位置和震级大致相当。综合研究认为鄂尔多斯北缘发生的公元849年地震震级约为7级，该区未来地震震级上限及其大震风险值得继续深入研... 相似文献
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Shigeaki Ono Tsuyoshi Iizuka Takumi Kikegawa 《Physics of the Earth and Planetary Interiors》2005,150(4):331-338
In situ X-ray diffraction measurements on a calcium aluminosilicate (CAS) phase have been carried out using a laser-heated diamond anvil cell up to a pressure of 44 GPa, employing a synchrotron radiation source. CAS is the major mineral formed from sediments subducted into the Earth's mantle. The sample was heated using a YAG laser after each pressure increment to relax the deviatoric stress in the sample. X-ray diffraction measurements were carried out at T = 300 K using an angle-dispersive technique. The pressure was calculated using an internal platinum metal pressure calibrant. The Birch–Murnaghan equation of state for the CAS phase obtained from the experimental unit cell parameters showed a density of ρ0 = 3.888 g/cm3 and a bulk modulus of K0 = 229 ± 9 GPa for K′0 = 4.7 ± 0.7. When the first pressure derivative of the bulk modulus was fixed at K′0 = 4, then the value of K0 = 239 ± 2 GPa. From the experimental compressibility, the density of the CAS phase was observed to be lower than the density of co-existing Al-bearing stishovite, calcium perovskite, calcium ferrite-type phases, and (Fe,Al)-bearing Mg-perovskite in subducted sediments in the lower mantle. Therefore, the density of subducted sediments in the lower mantle decreases with increasing mineral proportion of the CAS phase. 相似文献
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Filip P. Adamus 《Geophysical Prospecting》2020,68(8):2361-2378
We investigate the dependence of quasi P-wave phase velocity propagating in orthotropic media on particular elasticity parameters. Specifically, due to mathematical facilitation, we consider the squared-velocity difference, , resulted from propagation in two mutually perpendicular symmetry planes. In the context of the effective medium theory, may be viewed as a parameter evaluating the influence of cracks – embedded in the background medium – parallel to one or both aforementioned planes. Our investigation is both theoretical and numerical. Based on Christoffel's equations, we propose two accurate approximations of . Due to them, we interpret the aforementioned squared-velocity difference as being twice more dependent on , than on . To describe the magnitude of the dependence, we consider the proportions between the partial derivatives of . Further, it occurs that is influenced by the ratio of vertically propagating quasi P-wave to vertically propagating quasi S-wave. Anomalously high might be caused by the low P/S ratio, which in turn can be an indicator of the presence of gas in natural fractures or aligned porosity. Also, we carry out numerical sensitivity study, according to which is approximately twice more dependent on than on , twice more sensitive to than to , and equally dependent on as on . The dependence on and can be neglected, especially for small phase angles. We verify the approximations and perform the sensitivity study, using eight examples of the elasticity tensors. 相似文献
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Expression of Mammalian Metallothionein-I Gene in Cyanobacteria to Enhance Heavy Metal Resistance 总被引：2，自引：0，他引：2
Metallothionein (MT) from mammals is a low molecular weight (about 6–7 KD), and cystein-rich (20 cystein per molecular) protein (Vallee, 1991). So MT has the strong binding ability of metal such as Cd, Hg and Pd. Wild-typed cyanobacteria have their own metallothionein-like proteins, which are of low cysteine content and have weak ability to bind heavy metal. Therefore, it is imperative to transfer the MT-I gene from mammal into cyanobacteria cell for the absorption and accumulation of heavy metals in aqueous system including marine and lake ( Misra and Gedamu, 1989). We inserted the MT-I cDNA gene after the strong promoter PpsbA or Psmt into the intermediary vector pRL-439, and then pRL-MT was ligated with shuttle vector pKT-210 (a shuttle vector pDC-08 was used at an earlier time) to construct the shuttle expression vector pKT-MT. (The MT-I mutant -KKS- also was selected as aim gene.) Then the constructed vector was introduced into cyanobacterium Anabaena sp. PCC7120, Synechocystis sp. PCC6803 and Synechococcus sp. PCC7942 with triparental conjunctive transfer (Bryant, 1994). The expression efficiency is about 1%. We also used homologous recombination vector pTZ18-8 to introduce MT-I cDNA into chromosomes in cyanobacteria and got higher expression efficiency. Metal tolerance tests show that the transgenic cyanobacteria acquire metal resistance up to 60 μmol/g CdCl2 and expression efficiency up to 1045 μg MT/g fresh cells according to the data of ELISA. 相似文献
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Over the last 25 years, considerable changes have been observed in the littoral vegetation of 11 lakes within the Sejny Lake District. In eight lakes (Dowcień, Jurkowo, Kunis, Miałkie, Pilwie, Płaskie, Wiłkokuk, Zelwa) where Chara species dominated, their communities declined or disappeared completely. In four of these lakes (Dowcień, Jurkowo, Kunis and Miałkie), charophytes were replaced by communities of the class Potametea (mainly Nupharo-Nymphaeetum albae and Ceratophylletum demersi). In three other lakes (Pilwie, Płaskie and Wiłkokuk), the area covered by charophyte communities decreased. In Lake Zelwa, Charetum rudis and Charetum jubatae disappeared while Charetum tomentosae and Charetum fragilis expanded. A total area of charophyte communities remained approximately the same. A considerable increase in the water total hardness and concentration was noted in each of the eight lakes. In most of them increased levels of dissolved organic matter (measured as COD-KMnO4) and pH were detected as well. However, the increase in the concentration was smaller in Lakes Wiłkokuk and Zelwa in which only slight changes in the vegetation were observed. In the above two lakes, the concentration of dissolved organic matter decreased and low water colour values are now noted. In three lakes (Długie, Dmitrowo and Gajlik), the charophyte communities tended to expand under the condition of moderate or high (Lake Długie) concentration, while dissolved organic matter concentrations were low. These lakes are also characterized by low values of colour. Charophyte communities may persist in lakes for a long period of time even when there is a moderate increase in concentration until the colour of water distinctly increases (>20 mg Pt L−1). 相似文献
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The singular evolutive extended Kalman (SEEK) filter has been proposed recently by Pham et al. (1997) for data assimilation into numerical oceanic models. This filter has been applied in different realistic ocean frameworks and has provided satisfactory results ( Pham et al., 1997; Verron et al., 1998). However, the SEEK filter remains expensive in real operational assimilation. To reduce cost and obtain a better representativity, we introduce the idea ‘local correction basis'. Such basis however cannot be made to evolve according to the model without destroying its locality property. Therefore we shall keep this basis fixed and we augment it by a few global basis vectors which evolve. The resulting semi-evolutive partially local filter is much less costly to implement than the SEEK filter and yet can yield better results. In the first application, validation twin experiments are conducted in a realistic setting of the OPA model over the tropical Pacific Ocean. 相似文献
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Levent Şaylan Barış Çaldağ Fatih Bakanoğulları Hüseyin Toros Mustafa Yazgan Orhan Şen Yunus Özkoca 《洁净——土壤、空气、水》2011,39(5):491-501
Pollutants affect not only the environment in which they originate since they are also transported by air currents to other locations. For this reason, air pollution is a global problem for all countries and the air and water quality need to be monitored carefully. More information on precipitation chemistry is required to determine the source of pollution as well as its effects on the ecosystems. In this study, precipitation chemistry has been analyzed for the first time by using simple bulk collectors located at four different sites in Northwest Turkey for a period of two years. About 650 sequential rainwater samples were collected and analyzed for pH, electrical conductivity, anions such as , , Cl?, and cations such as Na+, K+, Mg2+, Ca2+, and . The selected sites were under the effect of different environmental factors. Our results showed that the highest and concentrations were measured in the Northwest of the research area. Additionally, it has been found that Ca2+ ions are abundant within all rainwater samples. 相似文献