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地震图缩微工作，原以中周期ＳＫ记录为主，全国基准台１９７９－１９９３年的全部ＳＫ记录图已完成缩微存档。为适应科研需要，从１９９４年起，缩微任务调整为同时完成ＳＫ台网和ＬＰ台网的有震记录图。按照缩微新模式，ＳＫ和ＬＰ两种记录不仅都实现了缩微化，而且缩微资料由书本型变为信息型，地震缩微胶片的利用价值大大提高。 相似文献
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《地震地磁观测与研究》1995,16(5):66-70
１９９４年ＳＫ和７６３（ＬＰ）记录地震图缩微目录地球物理研究所缩微组（中国北京１０００８１国家地震局地球物理研究所）地震图缩微工作，从１９９４年开始做了调整，改为同时承担全国基式地震仪台网中周期（ＳＫ）记录及全国７６３地震仪台网长周期（ＬＰ）记录的有... 相似文献
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国际地震学及地球内部物理学协会(IASPEI)在1977年8月大会上通过决议:“鉴于全球台站记录到的地震图是研究地震和地球构造的基础,而早期的地震图由于战争,灾害及变质多有损失;因此,有必要在各台系统地搜集并照像复制重要地震的地震图,以保存并可通过世界资料中心(WDC)取得。IASPEI 强烈要求全球地震台站与复制计划合作,在台站现场提供历史地震图及有关资料,以便照像复制。”随后,IASPEI 所属资料交换委员会建立了复制地震图工作组。 相似文献
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本文给出了中国地震图缩微库10年来已拍摄、存储的各类地震图,缩微胶片目录几十万张,可供用户查阅。同时,列举了已往用户对本库缩微胶片质量的评价,使未来用户能放心地使用本库资料。为进一步扩大服务范围,笔者对本库所属的新缩微系统功能做了简要介绍。地震图是当前地震、地球物理研究工作最基础的资料。如何保护好地震图,并使之有效地为科研服务,是大家十分关心的问题。我国利用现代仪器观测记录地震,已有八十多年的历史,特别是近年来,各类地震台发展很快,目前已近七百个,若按每个台平均每天出记录图两张算,则每年将出图五十多万张。如此大量的数目,如果让它连续积累,其数量是相当庞大的。不论在资料管理、资料共享、国际交换等方面都会带来相当的麻烦。要想解决这个问题,目前世界上较为成熟的方法,就是对地震图进行缩微化处理。并建立地震图缩微库。 相似文献
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IASPEI/UNESCO历史地震图和地震工作小组与历史地震图缩微计划地震图含有震源和地球内部构造的大量信息,是地震学和地球物理学研究的重要资料来源。地震图是在遍布世界各地的地震台站记录到的,仪器类型、记录格式不尽一致,资料的保管和使用也不统一,这些都给地震学家充分利用这些资料造成相当大的困难。时常是为了得到一张重要的地震图要花费很多时间和精力。随着地震学的发展,台站仪器标准化,地震 相似文献
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黎向东 《地震地磁观测与研究》1991,12(3):72-74
DW-417地震图缩微照像机是专为地震图缩微设计制造的。它是地震资料缩微保存及国际资料交换必不可少的重要仪器。在我们近十年的工作中。使用DW-417照像机缩微了几十万张地震记录图。本文重点介绍该仪器在长期使用中出现的一些电路故障及其分析处理。 相似文献
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林楚贞 《地震地磁观测与研究》1988,(6)
一、引言地震图是地震台所记录到的震源和地球内部构造大量信息的图纸,是地震学和地球物理学研究的重要资料来源。有了它可以做许多工作。如研究全球性的地震活动性,大地震的破裂过程,断层面的力学结构……等等。因此,如何珍惜和保护地震图,高效率的利用它,实现对这些资料的现代化管理,已经是很迫切的任务了。就目前来看,采用缩微技术是解决以上 相似文献
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介绍了 DW-417地震波缩微相机研制成功,文章指出这是我国地震记录存贮手段新的进展;简介了对该机进行技术鉴定的会议概况;说明该机研制成功解决了地震资料保存、使用和国内外交流的问题,满足了地震预报和地球物理研究工作的需要。 相似文献
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１９９６年８月全球Ｍ≥５．０地震动态根据地震学合作研究会（ＩＲＩＳ）地震数据管理中心提供的资料，１９９６年８月份全球范围内共发生Ｍ＞５．０的地震１１６次（见附表），其中Ｍ＞６．０地震１１次，Ｍ＞７．０地震２次，最大的一次地震发生在斐济群岛地区，震级为... 相似文献
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Gtz Schroth Luciana Ferreira Da Silva Marc‐Andree Wolf Wenceslau Geraldes Teixeira Wolfgang Zech 《水文研究》1999,13(10):1423-1436
The partitioning of rain water into throughfall, stemflow and interception loss when passing through plant canopies depends on properties of the respective plant species, such as leaf area and branch angles. In heterogeneous vegetation, such as tropical forest or polycultural systems, the presence of different plant species may consequently result in a mosaic of situations with respect to quantity and quality of water inputs into the soil. As these processes influence not only the water availability for the plants, but also water infiltration and nutrient leaching, the understanding of plant effects on the repartitioning of rain water may help in the optimization of land use systems and management practices. We measured throughfall and stemflow in a perennial polyculture (multi‐strata agroforestry), monocultures of peach palm (Bactris gasipaes) for fruit and for palmito, a monoculture of cupuaçu (Theobroma grandiflorum), spontaneous fallow and primary forest during one year in central Amazonia, Brazil. The effect on rain water partitioning was measured separately for four useful tree species in the polyculture and for two tree species in the primary forest. Throughfall at two stem distances, and stemflow, differed significantly between tree species, resulting in pronounced spatial patterns of water input into the soil in the polyculture system. For two tree species, peach palm for fruit (Bactris gasipaes) and Brazil nut trees (Bertholletia excelsa), the water input into the soil near the stem was significantly higher than the open‐area rainfall. This could lead to increased nutrient leaching when fertilizer is applied close to the stem of these trees. In the primary forest, such spatial patterns could also be detected, with significantly higher water input near a palm (Oenocarpus bacaba) than near a dicotyledonous tree species (Eschweilera sp.). Interception losses were 6·4% in the polyculture, 13·9 and 12·3% in the peach palm monocultures for fruit and for palmito, respectively, 0·5% in the cupuaçu monoculture and 3·1% in the fallow. With more than 20% of the open‐area rainfall, the highest stemflow contributions to the water input into the soil were measured in the palm monocultures and in the fallow. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
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M. N. French R. L. Bras W. F. Krajewski 《Stochastic Environmental Research and Risk Assessment (SERRA)》1992,6(1):27-45
A procedure for short-term rainfall forecasting in real-time is developed and a study of the role of sampling on forecast ability is conducted. Ground level rainfall fields are forecasted using a stochastic space-time rainfall model in state-space form. Updating of the rainfall field in real-time is accomplished using a distributed parameter Kalman filter to optimally combine measurement information and forecast model estimates. The influence of sampling density on forecast accuracy is evaluated using a series of a simulated rainfall events generated with the same stochastic rainfall model. Sampling was conducted at five different network spatial densities. The results quantify the influence of sampling network density on real-time rainfall field forecasting. Statistical analyses of the rainfall field residuals illustrate improvement in one hour lead time forecasts at higher measurement densities. 相似文献
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M. A. Kahn 《洁净——土壤、空气、水》2000,28(2):95-101
Red tide, a recurrent phenomenon has become conspicuous in several Kashmir lake ecosystems since 1991. The responsible organism (Euglena pedunculata), a rare flagellate rediscovered in the Kashmir Himalaya (Khan 1993) caused first and unprecedented red tide outbreak, constituting a maximum of 96% of resident numerical phytoplankton density in Dal Lake. At present, conflicting hypotheses exist on the generation of causal assemblage(s) imparting redness to waters: Jeeji Bai (1991) linked its origin to acid precipitation – a fallout of burning oil‐fields during the Gulf War – whilst Khan (1993) holds local factor(s) responsible. Field/experimental studies support the latter contention that the influx of untreated sewage, in unison with warm temperatures, high levels of PhAR, iron and interruption to hydrological flow‐pattern together with absence/or reduction in grazing activity created conducive environmental milieu for red tide outbreak. Dal Lake “red tide” drifted the bloom‐inoculum to other waters, including Lake Wular, where additional ecological niches were carved out, threatening the aesthetic value and biological diversity of Kashmir lakes. Ecological monitoring indicates frequent seasonal red tide occurrence in Dal Lake (including summer‐autumn event of 1998) which testifies its unabated eutrophication status. Further studies are needed on ecological adaptability and biogeographic distribution of this rare and unique red tide‐causing flagellate. 相似文献
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