新丰江6.1级水库地震前后的波速比变化     

冯锐 《地球物理学报》1977,20(3):211-221

广东省新丰江水库区于1962年3月19日发生6.1级地震。本文分析了1961年以来十四年间,特别是主震前后纵、横波速比V_p/V_s的变化过程。结果表明:波速比V_p/V_s在主震前出现了明显的负异常,总异常时间约为十一个月,于震前一个半月返回正常值,在主震震源附近的深水峡谷区异常幅度最大,异常时间和空间范围比一般构造地震的要小.后期几次强余震前也有异常变化。虚波速度在主震前存在某些异常特征。上述波速比的变化可以用扩容模式较好地解释。 波速比值是由两个台站的记录得到的。对虚波速度的计算采用了联合地震参数的方法。  相似文献   

水库地震与地质构造的关系   总被引：4，自引：1，他引：3       下载免费PDF全文

李祖武 《地震地质》1981,3(3):61

许多实例表明,水库地震与地质构造有十分密切的关系。本文根据一些实际资料着重讨论了水库地震与活动性强烈的大地构造区、断裂带、断块间差异运动之间的关系  相似文献   

PCBs and OCPs in sediments from Hongfeng Reservoir in Guizhou Province, China     

Zhongqing WEI Congqiang LIU Xiaobing LIANG Fushun WANG Shaofeng WANG 《中国地球化学学报》2006,25(B08):69-70

In this research, chlorinated hydrocarbons （polychlorinated biphenyls and organochlorine pesticides） were measured by GC-ECD in sediments from the Hongfeng Reservoir area. The concentrations of total PCBs range from 3.2 to 31.6 ng/g, among which PCB28, PCB52 are the major congeners with the concentrations from 0.5 to 4.6 ng/g, and from 0.4 to 28.1 ng/g, respectively. The concentrations of these pollutants decrease from surface to bottom, while the concentrations at 1-4 cm are lower than at 5-8 cm, suggesting the decline of PCBs input. TOC concentrations of sediment are found in a significant positive correlation with those of PCBs, suggesting that PCBs are mainly adsorbed on organic matter and particles. HCHs and DDTs are the predominant organochlorine pesticides with the concentrations ranging from 1.6 to 8.9 ng/g （average 3.2 ng/g） and 0.9 to 25.7 ng/g （average 7.8 ng/g）, respectively. β-HCH and γ-HCH （lindane） are the predominant HCH isomers from sediments, and p, p＇-DDE and p, p＇-DDT are the predominant DDT isomers. DDT/DDE＋DDD and α-HCH/γ-HCH ratios range from 0.6 to 0.9 and 0.1 to 3.0, respectively, which indicates more use of lindane than technical mixtures of HCHs before, and also suggests changes in HCHs and DDTs in the environment. The high values of β-HCH and p, p＇-DDE also show that atmospheric input is one of the important sources of the Hongfeng Reservoir, because β-HCH and p, p＇-DDE are stable and have low Sw and Pv so that they can be easily transferred over a long range in atmosphere.  相似文献   

Overcoming flood and desiccation made by implementing artificial recharge toward absorption reservoir     

Teddy W. Sudinda Teddy 《中国地球化学学报》2006,25(B08):156-157

Flood and desiccation are perceived as two most critical and influential disasters which contradict between causes and consequences. Flood occurs when the water surface could no longer flow the whole water flow, thus, the water flooded. Contradicted to that, desiccation occurs when the water flow contains a low volume of water deposit, thus, the water requirement exceeds the available potential. That condition was caused by land utilization as the consequences due to the increased land requirement for housing or industrial needs. An attempt to overcome the flood, nowadays, is implemented mostly in a structural way, through building canals, implementing rivers normalization, building gateways or building flood control pump which are more directed toward the flood direction in order to increase the surface flow in an immediate maner to the sea. However, the effort to overcome the flood its self, could be more effective if followed by an effort to increase the soil ability to absorb natural recharge or artificial recharge or by refilling the water into the earth surface. Absorption reservoir used as one of technology alternatives （artificial recharge） could also be used to support the attempt to overcome flood and desiccation. Absorption reservoir is a dam which was designed according to the basic principles, such as the bottom surface of the reservoir that has a high permeability surface; the surface of the reservoir water is higher （higher aquifer） along with a high permeability, considering the availability of water source that has been absorbed and its quality; considering the aquifer category on the water absorption dam;  相似文献   

Early diagenesis of nurtrients （C, N, P and Si） stored in sediments of two reservoirs in southwestern China     

Yuchun WANG Jun ZHU Congqiang LIU 《中国地球化学学报》2006,25(B08):161-162

Damming is a common anthropogenic intervention along the course of rivers, which is defined as ＂artificial-lake effect＂, both in China and across the world. Today as many as 48000 dams and/or reservoirs are in operation in the Changjiang River （Yangtze River） drainage area, and more are being constructed. While damming is well known to affect riverbome nutrient loads, and thus the riverine ecosystems owing to removal of carbon fixation, and removal of particles in reservoir sediments, there is limited information on the detailed early diagenesis of sediments in reservoirs including the regeneration processes of nutrients deposited in sediments and exchange flux across the sediment-water interface, which is important for mass balance of riverbome nutrients. In the present study, two large-size reservoirs, Wujiangdu Reservoir （WJDR） and Dongfeng Reservoir （DFR）, located on the main steam of the Wujiang River and with uniformity hydrography and discrepancy biogeochemical activity （e. g. primary production）, were selected for a comparative study on the detailed processes of nutrient regeneration. Water, pore water and sediment were sampled from these two reservoirs and dissolved organic carbon （DOC）, NH4^＋, NO3^-, PO4^3-, dissolved silica （DSi） in the overlying water and pore water, and total organic matter in sediments were determined. The results of correlation analysis suggested that in these two reservoirs, processes of nutrient regeneration near the sediment-water interface were significantly different. As a result of rapid decomposition of algae-derived ＂labile＂ organic matter in upper sediments, nutrient regeneration processes and upward fluxes in WJDR are dramatically stronger than those of DFR. NH4^＋ upward flux from sediment in WJDR was about 17 times higher than that in DFR. PO4^3- flux in WJDR is about 13 times above that in DFR. DOC flux in WJDR is larger that in DFR by 5 times, and DSi by 1 time.  相似文献   

实施流域生态管理的长江中下游湿地保护探讨   总被引：4，自引：1，他引：4  

鲍达明  王学雷  吕宪国 《湿地科学》2006,4(2):96-100

长江中下游地区湿地分布广泛且类型多样,是我国淡水湖泊分布最集中和最具有代表性的地区。为了从根本上解决长江中下游湿地利用面临的问题,实现湿地资源的可持续利用,保护湿地环境,解决区内上、下游用水的供需矛盾,实现水资源的优化配置,调动区域湿地保护的积极性和主动性,有必要遵循湿地流域分布规律,应用流域生态学最新理论与实践成果,进行流域生态管理。一方面,要从流域角度处理好几大江湖关系、蓄泄关系、湖垸关系和山湖(河)关系等;另一方面,在流域内建立统一协调机制,对流域湿地进行保护与合理利用、合理布局和统一规划;同时在保护的前提下,科学合理地利用长江中下游湿地资源,开拓新的生产力。  相似文献   

那棱格勒河流域及尾闾盐湖水文循环动力学模型的选择          下载免费PDF全文

王涛  高东林  马海州  张明刚 《盐湖研究》2006,14(4):18-22

流域水文模型的研制是水文科学中最重要的分支之一。其中包括集总式和分布式流域水文模型,分布式流域水文模型的种类很多,在我国的研究和应用比较普遍。那棱格勒河是柴达木盆地最大的一条河流,正确评价该河流的水文情况,对开发柴达木盆地盐湖资源具有十分重要的意义。应用分布式流域水文模型理论,对适用于那棱格勒河流域的水文循环动力学模型的类型进行选择,通过分析对比,选择出最适合本地区特殊条件的TOPKAPI模型,以便于探讨该地区水文循环的特点与规律,从而阐明盐湖区各类水体间的相互补给关系。  相似文献   

福建省山仔水库浮游植物特征与水体富营养状况分析     

苏玉萍  陈娜蓉  林婉珍  梁晓丹 《福建地理》2006,(4)

采用浮游植物指示法评价了福州省山仔水库2005年不同季节水体的富营养状况,结果表明:冬、春季库区水体处于中—富营养水平,夏季发生水华微囊藻(Microcystis flos-aquae)“水华”,水体处于富营养水平,秋季水体处于中营养水平.由于浮游植物的生长状况受到多因素的影响,有必要进一步结合其他评价方法对整个水体的富营养状态做出综合判断.  相似文献   

高原湿地保护国际研讨会于2006年6月26～29日在印度新德里召开     

张明祥 《湿地科学与管理》2006,2(3):F0003-F0003

2006年6月26日，国际山地综合发展中心和湿地国际组织召开了“通过亚洲湿地调查方法和利益共享者主导的流域管理方法支持喜马拉雅动议项目”研讨会。目的是以研讨会的形式召开项目启动会，交流介绍项目参加国的高原湿地现状，  相似文献   

燕山水库坝基防渗墙优化设计   总被引：1，自引：0，他引：1  

张宜虎  尹红梅  杨裕云  王亮清 《岩土力学》2005,26(7):1161-1164

因现场资料不足或分析手段落后等原因,当前进行水库坝基防渗墙设计,往往存在过于保守的倾向。以河南省燕山水库为例,基于优化设计的思路,采用目前较为成熟的二维有限单元法,对不同防渗条件下的坝基渗流场分别进行了模拟,并将计算所得比降、流量与允许比降、允许流量做了对比,从定量的角度提出了既安全、又经济的防渗方案:防渗墙厚度取0.8m,深度取打入破碎带5m。  相似文献