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991.
太平洋多金属结核及沉积物标准物质研制   总被引:8,自引:0,他引:8  
太平洋多金属结核及深海沉积物标准物质,GSPN-2,3和GSMS-2,3,4个样品已研制完成。GSPN-2,3和GSMS-2采自太平洋CC区,GSMS-3采自中太平洋海盆(CP区)。原样被加工成-200目(74μm)的均匀粉未,其均匀性采用高精度的X射线荧光光谱法检测。样品的特性值采用国内外多实验室协同分析的方式定值,有包括台湾大学在内的14个国内实验室和18个国外实验室参加了合作分析。测试组分分别达79和81个,定值组分63个。全组分的百分总和分别为:99.7%,99.5%,99.8%和99.7%。这4个标准物质已于1997年被国家技术监督局批准为国家一级标准物质,序号分别为GBW07295,GBW07296,GBW07315和GBW0731。  相似文献   
992.
周毅 《地球学报》1998,19(3):325-334
20世纪是人类物质文明最发达的时代,但也是地球生态环境和自然资源遭到破坏最为严重时期。不可持续的经济畸增的产生和消费模式使人类生存和发展面临严峻挑战。传统工业是一柄福音和灾祸的双刃剑,中国并不庞大的工业由于先天不足、粗放外延发展等原因过早地走入了破坏自然生态、人口急剧膨胀、环境污染不断加剧的尴尬境地,有可能重蹈发达国家“经济腾飞,公害泛滥”的覆辙。本文提出人口、生态、资源、环境、社会、经济、文明可持续发展新思路及可操作性对策是当务之急。  相似文献   
993.
基性岩墙群是大陆和大陆造山带内发育的特殊地质体,包含丰富的地球动力学信息。造山带内基底岩块是造山作用过程卷入造山带的外来或原地地块(陆块),基底岩块中基性岩墙群的发育及其变形、变质特征,既为造山带内存在古老陆块和古陆块的裂离提供了证据,也为造山过程的构造动力学研究提供了重要信息。加强造山带基底岩块中基性岩墙群的多学科综合研究,对于探讨大陆造山带的形成、演化及其动力学过程具重要意义。  相似文献   
994.
大洋温盐环流的稳定性及变率模拟研究进展   总被引:11,自引:2,他引:9  
围绕大洋温盐环流的稳定性和变率,以三维原始方程大洋环流模式(OGCM)和海气耦合模式为重点,兼顾理想概念模式,总结了近年来模拟研究的主要成果。概括了几个主要前沿方向——大洋温盐环流的多平衡态现象、数十年/年代际变率以及百年到千年尺度的变率特性等的研究成果,探讨了其内部机制。  相似文献   
995.
After an earthquake, earthquake emergency response and rescue are important ways to mitigate earthquake-induced losses. Various earthquake emergency maps can provide effective references and guidance to those actions. Currently, related studies include the investigation on symbols of emergency maps, remote sensing emergency mapping and GIS-based mapping methods. However, the existing studies overlook the characteristics of rapidity, dynamicity and variety of presentation methods in making earthquake emergency maps. In this paper, a map template matching method is used to quickly make earthquake emergency maps considering their characteristics. We take investigations on the service objects(users)of the earthquake emergency maps to understand the needs of making earthquake emergency maps. The audience theory in mass media field and map information transmission theory are adopted to classify the users of the earthquake emergency maps into four categories: earthquake emergency commanders, technical staffs for decision-making, earthquake emergency rescuers, and the public. The components of different types of users are described and then their diverse demands in earthquake emergency maps are analyzed, such as the needs of on-field disaster information maps, earthquake information maps, physical geography and social economic maps. Following those needs, we introduce the representation methods of the earthquake emergency maps according to their formats(vector or raster)and contents, such as point symbolization method, kilometer grid method, line symbolization method and range method. Then, we study the rapid plotting method of earthquake emergency map based on map template matching method. The core steps of the method include: 1)before earthquake, the templates of different earthquake emergency maps are designed, prepared and connect the earthquake emergency features with their related spatial database. The map layout and map elements are stored in the templates. 2)After earthquake, the earthquake emergency features will be generated from seismic models(such as attenuation model of earthquake magnitude and seismic intensity)or the information obtained from field investigation. 3)Corresponding earthquake emergency map template is selected in accordance with the generated seismic features. And the features are used to update related features inside the selected template. 4)Minor adjustments are made such as to the map scale and some map annotations to finally generate the formal earthquake emergency map. Architecture of template system of the earthquake emergency maps is designed, including map user level, map template level, template layer level and map element level. Regrading to the architecture, the general map template of earthquake emergency is presented which includes four main regions: title region, main picture region, auxiliary region and annotation region. The main picture region is the essential, which lays geographic background maps and earthquake emergency features. Finally, an earthquake emergency mapping system is developed. Based on the system, a case study is presented, which demonstrates making a simulated seismic intensity influence map. From three aspects, the case presents the application of the template-matching method including: generating earthquake emergency features, substituting the features inside the template with the generated features, and revising map annotations. Therefore, the map template matching method is verified so that it can be used to quickly generate various earthquake emergency maps.  相似文献   
996.
The Bolokenu-Aqikekuduk fault zone(B-A Fault)is a 1 000km long right-lateral strike-slip active fault in the Tianshan Mountains. Its late Quaternary activity characteristics are helpful to understand the role of active strike-slip faults in regional compressional strain distribution and orogenic processes in the continental compression environment, as well as seismic hazard assessment. In this paper, research on the paleoearthquakes is carried out by remote sensing image interpretation, field investigation, trench excavation and Quaternary dating in the Jinghe section of B-A Fault. In this paper, two trenches were excavated on in the pluvial fans of Fan2b in the bulge and Fan3a in the fault scarp. The markers such as different strata, cracks and colluvial wedges in the trenches are identified and the age of sedimentation is determined by means of OSL dating for different strata. Four most recent paleoearthquakes on the B-A Fault are revealed in trench TC1 and three most recent paleoearthquakes are revealed in trench TC2. Only the latest event was constrained by the OSL age among the three events revealed in the trench TC2. Therefore, when establishing the recurrence of the paleoearthquakes, we mainly rely on the paleoearthquake events in trench TC1, which are labeled E1-E4 from oldest to youngest, and their dates are constrained to the following time ranges: E1(19.4±2.5)~(19.0±2.5)ka BP, E2(18.6±1.4)~(17.3±1.4)ka BP, E3(12.2±1.2)~(6.6±0.8)ka BP, and E4 6.9~6.2ka BP, respectively. The earthquake recurrence intervals are(1.2±0.5)ka, (8.7±3.0)ka and(2.8±3)ka, respectively. According to the sedimentation rate of the stratum, it can be judged that there is a sedimentary discontinuity between the paleoearthquakes E2 and E3, and the paleoearthquake events between E2 and E3 may not be recorded by the stratum. Ignoring the sedimentary discontinuous strata and the earthquakes occurring during the sedimentary discontinuity, the earthquake recurrence interval of the Jinghe section of B-A Fault is ~1~3ka. This is consistent with the earthquake recurrence interval(~2ka)calculated from the slip rate and the minimum displacement. The elapsed time of the latest paleoearthquake recorded in the trench is ~6.9~6.2ka BP. The magnitude of the latest event defined by the single event displacement on the fault is ~MW7.4, and a longer earthquake elapsed time indicates the higher seismic risk of the B-A Fault.  相似文献   
997.
气候突变的聚类分析   总被引:9,自引:2,他引:7       下载免费PDF全文
气候数据是时间序列,是一类有序样品.本文给出了一种新的有序样品谱系聚类算法,先对数据进行平滑拟合,然后用聚类分析的方法分析了北半球的气候资料,证实了1920年为气候突变点.同时也找到了较低的各个层次上的突变点.  相似文献   
998.
依据研究区的地热梯度(25℃/km),在高温高压(最高温度为1050℃,最高压力为1.2GPa)条件下系统测量了横穿红河-哀牢山断裂带的元江-墨江地质剖面上的哀牢山岩群各类变质岩(千枚岩、片岩、浅粒岩、变粒岩、大理岩和片麻岩)的纵波速度.实验结果表明,不同岩类的纵波速度随温度压力变化的趋势不同.在相当于衷牢山岩群变质岩峰期变质温度和压力条件下(P=0.4-0.8GPa,T=35-700℃),测得大部分岩石的纵波速度为5.50-5.80km/s,这一纵波速度值与区域地球物理测深揭示的中地壳低速层的纵波速度相当因此,结合该区变质岩、地壳内热状态及地球物理测深研究成果可初步认为:组成哀牢山岩群的浅粒岩、变粒岩、酸性片麻岩以及部分千枚岩、片岩为该地区中地壳低速层的主要岩石类型.  相似文献   
999.
依据三角测量资料分析云南小江断裂北段的应力场   总被引:1,自引:0,他引:1       下载免费PDF全文
本文试图利用小江断裂北段1956年和1967年两次二等三角测量的资料分析本区的应力场.其结果表明,此区内主压应变轴走向大都近于北西西向即近期承受北西西向的压应力作用.  相似文献   
1000.
关于黄土碳酸盐与气候环境关系探讨   总被引:1,自引:0,他引:1  
黄土中碳酸盐与气候环境密切相关。从碳酸盐的成因看,干冷的气候利于原生碳酸盐的保存,而温湿的气候使大量的次生碳酸盐产生。碳酸盐的存在形式与降水量多少有关,降水量大可形成结核层和钙板等,而降水量小则形成各种胶膜。胶膜中各种不同形态的方解石胶膜又可反映不同的气候条件。黄土一古土壤中形成的碳酸盐实际上在古土壤期形成的碳酸盐要高于黄土期形成的,只是由于古土壤期强烈的风化淋溶作用,大量的碳酸盐从古土壤中淀积到下伏的黄土层中。黄土中CaCO3的淀积可分为连续淀积和不连续淀积两类。依据淀积深度和降水量的关系,可建立二者定量的关系。从黄土碳酸盐的不同方面,得到其与气候环境关系较为全面的认识。  相似文献   
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