Attenuation relations of ground motion for rock and soil sites in eastern United States     

Howard Hwang  Jun-Rong Huo 《Soil Dynamics and Earthquake Engineering》1997,16(6):363-372

This paper presents the attenuation relations of peak ground acceleration and spectral accelerations for rock and soil sites in the central and eastern United States (CEUS). For the bedrock site condition, 56 pairs of moment magnitude M and epicentral distance R are used to simulate ground motion, and for each pair of M and R, 550 samples of ground motion parameters are generated using a seismological model together with random vibration theory and distribution of extreme values. From the regression analyses of these data, the attenuation relations of ground motion parameters for the bedrock site are established. With the aid of appropriate site coefficients, these attenuation relations are modified for the site categories specified in the 1994 NEHRP Provisions. These attenuation relations are appropriate for the assessment of seismic hazards at far-field rock and soil sites in the CEUS.  相似文献   

蚀变岩中物质迁移的定量计算：以锡矿山锑矿床为例   总被引：6，自引：2，他引：6  

解庆林  马东升 《地质论评》1997,43(1):106-112

本文提出了确定沉积岩蚀变作用过程中的不活动组分的方法，并以锡矿山锑矿床为例，定量计算了蚀变岩中各组分的带入带出量，研究表明：锡矿山锑矿硅化过程中ＴｉＯ２和Ａｌ２Ｏ３为不活动组；ＳｉＯ２，Ｋ２Ｏ，Ｎａ２Ｏ及锑，硫，坤，汞，铅和钡为带入组分；而ＣａＯ，ＭｇＯ，Ｆｅ２Ｏ３，ＭｎＯ及铜，锌为带出组分，锑，钡，硫，ＳｉＯ２和ＣａＯ有较大的带进或带出量，锡矿山锑矿床矿石矿物为单一辉锑矿可能是由于矿液中缺少其它  相似文献   

The characteristics of Quaternary activity of faults in the sea area near the Yangtze River mouth     

章振铨  火恩杰  刘昌森  王锋 《地震学报(英文版)》2004,17(4):473-479

Introduction As far as the frequency and magnitude are concerned, the earthquakes in the sea area to the east of Shanghai are far more strong than in land area with the largest one in the sea area near the Yangtze River mouth being MS=436, while in land, only MS=434 occurred on Sept. 1, 1624. As a moderately strong earthquake active area, the sea area near the Yangtze River mouth, may cause a potential risk to Shanghai. In 1971 and 1996, earthquakes with MS=5~6 occurred in this area. Geo…  相似文献   

Preliminary Study on Cenozoic Group and Fault Activity in the Sea Area Near the Yangtze River Mouth   总被引：2，自引：0，他引：2  

Huo Enjie 《中国地震研究》2004,18(1):13-26

By shallow seismic prospecting, the Cenozoic Group in the sea area near the Yangtze Rver Mouth can be divided into five seismic sequences. They correspond to the Quaternary,Pliocene, Upper Miocene, Lower Miocene and Eocene respectively. The Quaternary System covers all the detecting area. The Tertiary System overlaps and thins out from NE to SW. The sedimentary basement mainly consists of volcanic rock (J3) and acidic rock (r35). Paleogene or Late Cretaceous basins are not found there. The faults that have been detected are all normal faults. They can be divided into three groups (NE, NW, near EW) by their trend. The NE and NW-trending faults are predominant, and agree with aeromagnetic anomaly. Their length and displacement are larger than that of the EW-trending faults. The activity of the NEtrending faults is different in different segments. The SW segment is a Quaternary fault, the middle segment is a Neogene fault, The NE is Paleogene. But the segment of the NW-trending fault is not obvious. The average vertical displacement rate is about 0.015mm/a.  相似文献   

内外网中转程序介绍          下载免费PDF全文

李定平  付东升  贺建中 《山西气象》2005,(3):22-23

为了防止计算机病毒的干扰,保证基础气象业务的正常运行,阳泉市气象局的局域网分为内网和外网,内网上的计算机用于基础气象业务,外网上的计算机都可以上互连网。为了方便内外网的信息交换,在内外网之间安装一台计算机,运行内外网中转程序,使内外网的文件基本达到同步更新。这样既保证了内网上的计算机运行稳定,又满足了外网上的计算机对内网上气象信息的需求。  相似文献   

GEOCHEMICAL CHARACTERISTICS OF PLATINUM GROUP ELEMENTS IN JINCHUAN SUPER-LARGE SULFIDE COPPER-NICKEL DEPOSIT, JINCHANG CITY, GANSU PROVINCE, CHINA     

WANG Ruiting MAO Jingwen HE Ying WANG Dongsheng TANG Zhongli 《大地构造与成矿学(英文版)》2005,29(2):152-163

The platinum-group element geochemistry of rocks and ores from Jinchuan super-large copper-nickel sulfide deposit is systemically studied in this paper. The Cu/Pd mean ratio of Jinchuan intrusion is lower than that of original mantle magma, which indicates that these ultrabasic rocks were crystallized from magma that lost Pd in the form of melting segregation of sulfides. The PGE of the rocks show trend of partial melting, similar to that of mantle peridotite, which shows that magma formation occurs during rock-forming and ore-forming processes. The chondrite normalized PGE patterns of the rocks and ores are well related to each other, which signifies the signatures of multi-episode magmatic intrusion, melting and differentiation in the formation processes of rocks and ores. In addition, analyses about the relation between PGE and S, and study on Re-Os isotopes indicate that few contamination of the crustal substances occurred during the magmatic intrusion and the formation of deposit. However, contamination by crustal substances helps to supply part of the S for the enrichment of PGE. Meanwhile, the hydrothermal process is also advantageous for the enrichment of PGE, especially lbr Pt and Pd, due to deep melting segregation. The characteristic parameters （such as Pt/（Pt＋Pd）, （Pt＋Pd）/（Ru＋Ir＋Os）, Pd/Ir, Cu/（Ni＋Cu）, and so on.） for platinum-group elements for Jinchuan sulfide copper-nickel deposit show the same features as those for sulfide copper-nickel deposit related to basic magma, which also illustrates its original magma property representative of Mg-high tholeiite. Therefore, it is the marie （not ultramafic） magma that resulted in the formation of the superlarge sulfide copper-nickel deposit enriched in Cu and PGE. To sum up, the geochemical characteristics of platinum-group elements in rocks and ores from Jinchuan copper-nickel sulfide deposit are constrained by the continental rift tectonic environment, the parent magma features, the enriched mantel magma source, the complex metallogenesis and PGE geochemical signatures, and this would be rather significant for the study about the genetic mechanism of copper-nickel sulfide deposits.  相似文献   

A nonstationary extreme value distribution for analysing the cessation of karst spring discharge          下载免费PDF全文

Yan Liu  Yonghong Hao  Yonghui Fan  Tongke Wang  Xueli Huo  Youcun Liu  Tian‐Chyi J. Yeh 《水文研究》2014,28(20):5251-5258

The effects of climate change and population growth in recent decades are leading us to consider their combined and potentially extreme consequences, particularly regarding hydrological processes, which can be modeled using a generalized extreme value (GEV) distribution. Most of the GEV models were based on a stationary assumption for hydrological processes, in contrast to the nonstationary reality due to climate change and human activities. In this paper, we present the nonstationary generalized extreme value (NSGEV) distribution and use it to investigate the risk of Niangziguan Springs discharge decreasing to zero. Rather than assuming the location, scale, and shape parameters to be constant as one might do for a stationary GEV distribution analysis, the NSGEV approach can reflect the dynamic processes by defining the GEV parameters as functions of time. Because most of the GEV model is designed to evaluate maxima (e.g. flooding, represented by positive numbers), and spring discharge cessation is a ?minima’, we deduced an NSGEV model for minima by applying opposite numbers, i.e. negative instead of positive numbers. The results of the model application to Niangziguan Springs showed that the probability of zero discharge at Niangziguan Springs will be 1/80 in 2025, and 1/10 in 2030. After 2025, the rate of decrease in spring discharge will accelerate, and the probability that Niangziguan Springs will cease flowing will dramatically increase. The NSGEV model is a robust method for analysing karst spring discharge. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

基于Fisher判别的南方双季稻低温灾害等级预警   总被引：4，自引：3，他引：1       下载免费PDF全文

吴立  霍治国  杨建莹  肖晶晶  张蕾  于彩霞  张桂香 《应用气象学报》2016,27(4):396-406

为了建立南方双季稻低温灾害综合预测预警技术体系, 基于南方双季稻种植区1961—2010年708个气象站的逐日气象资料、水稻生育期资料和低温灾害发生的气象行业标准,采用Fisher判别分析法、因子膨化法、相关性分析法,利用SPSS软件构建早稻春季低温灾害高风险区 (Ⅰ区) 未来10 d、晚稻寒露风高风险区 (Ⅰ区)、主灾区 (Ⅱ区) 未来5 d的低温灾害发生等级逐日滚动预警模型。其中,1961—2009年资料用于模型构建和回代检验,2010年资料用于模型的外延预测。结果表明:早稻、晚粳稻、晚籼稻Ⅰ区平均外延预测基本一致准确率分别达到90.5%,74.2%,80.3%,晚粳稻、晚籼稻Ⅱ区平均外延预测基本一致准确率分别为89.4%和80.3%。构建的南方双季稻低温灾害逐日滚动预警模型的外延预测基本一致准确率多超过80%,等级预测检验误差总体上在1个等级以内,模型评价效果较好。  相似文献   

Growth performance of larval and juvenile manila clam (<Emphasis Type="Italic">Ruditapes philippinarum</Emphasis>) from divergently selected individuals of a full-sib family     

Zhongming Huo  Xiaotong Li  Qian Sun  Yongren Li  Xuekai Zhang  Xiwu Yan  Feng Yang 《中国海洋大学学报(英文版)》2016,15(6):1046-1050

In this study, the method of divergent selection was employed to test the larval and juvenile growth performance within a full-sib family of Manila clam Ruditapes philippinarum. The 10% largest and 10% smallest clam individuals (on the basis of shell length) of a full-sib family were selected as parents for the fast and slow growing lines, respectively. The difference in shell length was significant among the three lines (fast, control, and slow) tested. The sequence of shell length were fast line > control line > slow line. The responses to selection, realized heritability, and genetic gain were 0.06%–0.81%, 0.04%–0.47% and 0.58%–18.89% in the fast direction, respectively; and were 0.14%–1.27%, 0.08%–0.73%, and 0.31%–49.03% in the slow direction, respectively. The results suggested that there was a large portion of additive genetic variance affecting the growth in the full-sib family. Selection in the fast direction within the full-sib family would greatly improve the growth of R. philippinarum.  相似文献   

Soil and water conservation in mining area based on ground surface subsidence control: development of a high-water swelling material and its application in backfilling mining     

Ailong Wang  Liqiang Ma  Zhongwei Wang  Dongsheng Zhang  Ke Li  Yao Zhang  Xingjun Yi 《Environmental Earth Sciences》2016,75(9):779

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