金沙江攀枝花段水系沉积物中重金属的分布特征及污染评价   总被引：2，自引：1，他引：2  

徐争启  倪师军  张成江  庹先国  滕彦国 《物探化探计算技术》2004,26(3):252-255

对攀枝花地区金沙江水系沉积物中九个重金属元素的地球化学特征及空间分布特征进行了分析研究,并对各重金属的污染程度进行了初步评价。研究发现,重金属在支流与金沙江交汇点下游处含量高于上游处,这说明金沙江有一定的自净化能力。通过分析可知,重金属的污染程度为:Cu>V>Ti>Mn>Cr>Zn>As>Co>Pb,其中Cu、V、Ti、Mn污染严重,Pb为轻度污染。污染最严重的地区是攀钢冶金区、攀钢选矿区、攀钢采矿区以及攀钢尾矿坝。  相似文献   

Deflation rates of different clastic sediments in the arid regions of China     

SONG Yang  LIU Lianyou  LI Xiaoyan  WANG Jianhua  TUO Wanquan  LIU Yuzhang 《地理学报》2006,16(4):495-501

By wind tunnel experiment, we studied the deflation rates of 8 different clastic sediments in the arid regions of China, discussed the sources of aeolian sand and their influence on the development of sand dunes and formation of sand deserts from the view of dynamics of wind erosion. The average deflation rates of 8 typical clastic sediments in the arid regions of China can be arranged in the order of lacustrine sand > alluvial sand > weathered sandstone and shale > pluvial sediments > fluvioglacial sand > weathered granite > slope deposit > glacial sediments. The deflation rates exhibited strong positive correlations with the erodible particle (0.063–2mm) content and sorting features. In contrast, the deflation rates had obvious negative correlations with the contents of silt clay (<0.063 mm) and gravel (>2 mm). According to the deflation rates, the 8 typical clastic sediments can be divided into four categories: (1) lacustrine and alluvial sand, which are readily prone to wind erosion, assumed to be the main source of aeolian sand; (2) weathered sandstone and shale, pluvial sediments and fluvioglacial sand with considerable deflation rates, might be the secondary source of aeolian sand; (3) weathered granite and slope deposit having the lower deflation rates, could supply a little aeolian sand; and (4) glacial sediments with a strong anti-erodibility, could hardly offer any aeolian sand. In addition to the strong wind conditions, the exposure of extensive lacustrine sand induced by the desiccation of inland lake basin, as well as the pre-sorting of clastic sediments by flowing water should be the key factors influencing the development of sand deserts in China. The possible reason the sand deserts in China being mostly distributed around the inland lake basins and along riverbanks could be better understood through sand source analysis.  相似文献   

NUMERICAL STUDY OF THE ABNORMAL TRACK OF TYPHOON MAGGIE     

张中锋  刘启汉  拓瑞芳 《热带气象学报(英文版)》2006,12(2):174-178

Typhoon Maggie (1999) interacted with another tropical depression system and moved along a west-southwest track that is somewhat abnormal during its pre-landing stage. Two numerical experiments are carried out in this paper to study the effect of the interaction on the track of typhoon Maggie using the mesoscale numerical weather prediction model system with a tropical cyclone bogusing scheme developed by Center for Coastal and Atmospheric Research, the Hong Kong University of Science and Technology. Results show that the cyclone system interacting with Maggie is the main factor for the abnormal track of Maggie.  相似文献   

VERIFICATION TEST OF THE PHYSICAL MODEL IN WUHAN FOR THE GEZHOUBA DAM REGION WITH RESPECT TO ITS FIRST STAGE CONSTRUCTION IN OPERATION ── A SUMMARY REPORT     

Lin Wanquan  Wang Mingna 《国际泥沙研究》1989,(1)

I. INTRODUCTIONThe Gezhouba Project is located on the main stem of the Yangtze River with a total installed capacity of 2750 MW. The general layout of the project is shown in Fig. l--a. The drainage area upstream of the project is 1 million sq. km with an…  相似文献   

The effect of the coarse aeolian sand on siltation of the Inner Mongolian Reach of the Yellow River     

Wanquan Ta  Gensheng Yang  Jianjun Qu  Tao Wang  Fennian Dai 《Environmental Geology》2003,43(5):493-502

  相似文献   

攀枝花地区昔格达土的土壤层环境地球化学特征   总被引：8，自引：0，他引：8  

滕彦国  倪师军  庹先国  张成江 《地质灾害与环境保护》2002,13(4):16-20

攀枝花地区昔格达土系粉砂壤土和粉砂土，土壤中原生矿物主要为石英和长石，次生矿物主要为蒙脱石，伊利石和高岭石。昔格达土不同层痊稀土元素分布特征相似，稀土元素在成土过程中没有明显的地球化学迁移，对母岩具有一定的继承性。昔格达土各层位Ti、V、Cr、Ni、Cu、Zn、Pb、As、Cd等元素具有较高的地球化学背景，在地表水和地下水的作用下容易释放进入环境，造成环境污染。  相似文献   

辽河盆地埋藏史及烃源岩成熟度演化史的数值模拟   总被引：9，自引：2，他引：9  

秦承志  王先彬  林锡祥  妥进才  周世新 《沉积学报》2002,20(3):493-498

对辽河盆地烃源岩的埋藏史、热演化史建立了准三维模型 (X、Y和纵向的地质层段, 加时间 )并编制了相应程序。模型采用回剥法并考虑了不整合情况以恢复各凹陷的埋藏史, 根据古地温资料计算相应的TTI史, 依据TTI-Ro 关系式得出烃源岩Ro 的演化过程, 进而恢复成熟度演化史。模拟结果表明 :东部凹陷发育了牛居地区和高力房-荣兴屯两个沉积中心, 西部凹陷发育了台安地区和盘山-大清水沟两个沉积中心, 大民屯凹陷发育了静安堡以北地区和荣胜堡两个沉积中心 东部凹陷沙三段、西部凹陷沙四段及沙三段、大民屯凹陷沙四段及沙三段至今均已全段或大范围进入生油门限, 是辽河盆地主要生烃段。  相似文献   

地学核技术识别成矿流体地球化学界面的试验   总被引：1，自引：1，他引：1  

庹先国  滕彦国  程渤  倪师军  张成江  童纯菡 《物探化探计算技术》2002,24(1):12-15

作者在本文中应用地学核技术方法进行了成矿流体地球化学界面的识别试验，结果表明，多元素X射线荧光测量技术、地气中子活化分析技术、γ能谱测量技术均可有效地识别地球化学界面的标志。  相似文献   

一种新的稳健估计方法的权函数选取     

脱立文  吴友平 《测绘与空间地理信息》2008,31(1):181-182

介绍了利用误差分布律的概率密度函数定义权函数的一种稳健估计方法。首先从理论上阐述了此种稳健方法的计算步骤,并通过实例同最小二乘法和几种稳健估计方法(Huber估计法、Hampel估计法、丹麦估计法)作了比较;证明了此种方法的优越性。  相似文献   

兰州市沙尘和非沙尘天气降尘的粒度特征比较   总被引：7，自引：3，他引：4  

李玉霖  拓万全  崔建垣 《中国沙漠》2006,26(4):644-647

选择兰州市典型沙尘天气和非沙尘天气收集两类降尘,并对其进行粒度测定。结果表明：两种类型降尘粒度特征差别明显。总体上看沙尘天气和非沙尘天气降尘都以粉砂为主,但沙尘天气降尘粒度比非沙尘天气降尘偏粗,分选更差。非沙尘天气降尘粒度频率曲线呈双峰态分布。而沙尘天气降尘则呈单峰正偏态分布特征,说明沙尘天气沉降物来源比较单一。沙尘天气和非沙尘天气降尘的粒度分布曲线与兰州黄土的十分相似,说明现代降尘是地质时代风尘活动的继续,现代风积作用仍在进行。而它们粒度参数之间的差异可能与降尘堆积物的粘土化过程有关。  相似文献