安徽宁芜地区铁氧化物-磷灰石矿床中金云母Ar-Ar定年及其地球动力学意义   总被引：23，自引：11，他引：12  

袁顺达  侯可军  刘敏 《岩石学报》2010,26(3):797-808

铁氧化物-磷灰石型铁矿床是长江中下游成矿带的重要组成部分,对其成岩成矿时限的精确厘定,是理解长江中下游地区中生代大规模成矿作用的动力学演化的关键。本文分别对宁芜盆地南部白象山、和睦山及中部的陶村三个大-中型铁矿床中与磁铁矿密切共生的金云母单矿物进行了Ar-Ar同位素测年,获得白象山矿床金云母Ar-Ar坪年龄为134.9±1.1Ma,对应的反等时线年龄为133±2Ma;和睦山矿床金云母Ar-Ar坪年龄为132.9±1.1Ma,对应的反等时线年龄为133.9±2.4Ma;陶村矿床金云母的反等时线年龄为128±14Ma。该区铁氧化物-磷灰石型矿床与该区火山-次火山岩具有密切的时间联系,成岩成矿时限主要集中于135～126Ma。综合研究表明,长江中下游第二期成岩成矿作用的时限为135～126Ma,对应于岩石圈的大规模快速减薄的地球动力学背景。  相似文献   

华北地台南缘张士英岩体的锆石SHRIMP U-Pb测年、Hf同位素组成及其地质意义   总被引：6，自引：3，他引：3  

向君峰  赵海杰  李永峰  程彦博  高亚龙  侯可军  董春艳  李向前 《岩石学报》2010,26(3):871-887

张士英岩体位于华北地台南缘,岩石类型包括钾长花岗岩、似斑状花岗岩和石英斑岩脉,其中只在钾长花岗岩中发育有暗色岩石包体,在包体和寄主岩中发育反映岩浆混合作用的岩石结构。钾长花岗岩、似斑状花岗岩和石英斑岩脉的SHRIMP锆石U-Pb年龄分别为107.3±2.4Ma、106.7±2.5Ma和101±3Ma。锆石Hf同位素分析结果显示,钾长花岗岩的锆石εHf(t)为-15.96～-20.80,单阶段模式年龄(tDM1)为1396～1643Ma,两阶段模式年龄(tDM2)为1880～2018Ma;似斑状花岗岩的锆石εHf(t)为-18.97～-22.18,tDM1为1512～1640Ma,tDM2为1925～2080Ma;除了一粒年龄为2.6Ga的锆石具有εHf(t)为-0.71、tDM1为2943Ma和tDM2为3036Ma的组成,石英斑岩的锆石εHf(t)为-23.41～-27.95,tDM1为1678～1896Ma,tDM2为2144～2330Ma。这些数据暗示,除了存在少量太古宙地壳物质的贡献外,张士英岩体的物质来源可能主要为1.9～2.3Ga期间形成的新生地壳,但也不排除古老地壳与富集地幔源混合的可能。综合分析前人研究成果表明,在太平洋板块俯冲方向发生转变的过程中,先存断裂带发生拉张。张士英岩体与中国东部同期岩浆活动一起可能形成于这种受断裂带控制的伸展环境。  相似文献   

碳酸盐岩中锶元素地球化学特征及其指示意义   总被引：7，自引：0，他引：7  

倪善芹  侯泉林  王安建  琚宜文 《地质学报》2010,84(10):1510-1516

应用锶指示古环境的方法很多,其中以锶的含量和与Sr配对的相应的元素比值作为指示剂,具有典型代表性。本文以北京下古生界碳酸盐岩为研究对象,采用ICP-MS分析技术测试了49件样品中Sr、Ba、Cu的含量。以锶的含量、Sr/Ba、Sr/Cu比值作为地化指标,深入探讨了锶的地球化学特征。系统的分析了Sr含量,Sr/Ba、Sr/Cu比值对不同的沉积环境的地质响应。指出从浅海环境到深海环境Sr含量及其相应的元素比值增加趋势明显,对沉积环境具有重要的指示作用。并且,Sr的分布还受到不同沉积旋回的影响,研究沉积作用对Sr分布的影响时,应在同一沉积旋回中进行。此外还深入研究了不同岩性、不同沉积旋回中Sr的分布特征,探讨了影响Sr分布的不同因素。归纳了锶对沉积环境的指示作用。就成岩作用对碳酸盐岩中锶分布的影响,结合前人的工作,进行了探索性的分析。  相似文献   

上海城市降雨径流污染时空分布与初始冲刷效应   总被引：44，自引：0，他引：44  

常静  刘敏  许世远  侯立军  王和意  Ballo Siaka 《地理研究》2006,25(6):994-1002

选取上海市中心城区典型功能区监测降雨事件,研究降雨径流污染时空变化及初始冲刷效应。研究表明,上海中心城区路面径流主要污染物为TSS和CODCr,超出国家地表水Ⅴ类标准四倍多;总磷超出Ⅴ类水质标准两倍以上,氮素营养盐也有不同程度的污染。污染物含量在不同功能区之间显示出相似的分布趋势,交通区明显高于其他区域,其次为商业区和工业区,居民区情况较为良好。降雨强度是影响初始冲刷效应的主要因素,强度较大的降雨冲刷效应较为明显;不同功能区之间,商业区初始冲刷效应较强,其次为居民区和工业区,交通区冲刷强度较弱;TSS和CODCr在商业区和工业区冲刷强度要大于氮磷污染物质;而在交通区和居民区分异特征不明显。  相似文献   

Polychlorinated biphenyls and polybrominated diphenyl ethers in surface sediments from the Yangtze River Delta   总被引：4，自引：0，他引：4  

Shen M  Yu Y  Zheng GJ  Yu H  Lam PK  Feng J  Wei Z 《Marine pollution bulletin》2006,52(10):1299-1304

  相似文献   

On quasi-periodic motions around the triangular libration points of the real Earth–Moon system     

X. Y. Hou  L. Liu 《Celestial Mechanics and Dynamical Astronomy》2010,108(3):301-313

The two triangular libration points of the real Earth–Moon system are not equilibrium points anymore. Under the assumption that the motion of the Moon is quasi-periodic, one special quasi-periodic orbit exists as dynamical substitute for each point. The way to compute the dynamical substitute was discussed before, and a planar approximation was obtained. In this paper, the problem is revisited. The three-dimensional approximation of the dynamical substitute is obtained in a different way. The linearized central flow around it is described.  相似文献   

Response prediction using the PC-NARX model for SDOF systems with degradation and parametric uncertainties     

Gao Xiaoshu  Chen Cheng  Hou Hetao  Jiao Shenghu 《地震工程与工程振动(英文版)》2022,(2):325-340

Building collapses during recent earthquakes have brought up the need for research on factors pertaining to collapse and the safety of structures.This requires ...  相似文献   

Soil bacterial functional diversity as influenced by cadmium,phenanthrene and degrade bacteria application   总被引：1，自引：0，他引：1  

Wei Jiang  Jijun Wang  Jianshe Tang  Feng Hou  Yitong Lu 《Environmental Earth Sciences》2010,59(8):1717-1722

There are increasing concerns over compound pollution in northeast of China and its bioremediation. Cd, Phe, degradation bacteria W.J and their combination on soil microbial community function were assessed with the BIOLOG method. The microbial community was extracted from the soil with different treatments. Average color development, richness, Shannon–Weaver index, and principal component analysis on OD standardized data were performed. The results showed that soil microbial metabolic diversity in CK was significantly higher than that in the soils in which Cd, Phe, W.J or their combination was added. It indicated that Cd, Phe has significantly negative effect on the sole-carbon-source metabolic ability of soil microbial communities, particularly when both of them were present. Application of degradation bacteria incubation makes soil microbial communities same as control except for the significant decrease in 4-hydroxy benzoic acid, l-serine, glucose-1-phosphate metabolism. It shows that the incubate application has a considerably effect in soil communities reversion.  相似文献   

The decay kinetics of residual chlorine in cooling seawater simulation experiments   总被引：1，自引：0，他引：1  

ZENG Jiangning  JIANG Zhibing  CHEN Quanzhen  ZHENG Ping  HUANG Yijun 《海洋学报(英文版)》2009,28(2):54-59

To find out the decay character of residual chlorine (RC) in the sea water, the concentration of RC was analyzed by N, N-diethyl-p-phenylenediamine (DPD) method under different simulation experimental conditions, in which salinity, temperature, and Chemical Oxygen Demand (COD) were selected. The water used in the experiment was the mixture of aging ocean water, coastal water and extracting solution of coastal sediment at appropriate level. Results are shown as follows:(1) Piecewise function can well reflect the decay dynamics of RC in the cooling seawater. Concretely, the decay dynamics of first 1 min is too rapid to ascertain using a specific kinetic function, and that of the time from 1 to 30 min is fit for the first-order kinetic model. (2) The results could be the foundation of the chemical behavior of RC in seawater, and be used as not only the guidance of the coastal power plants production and sea water desalting companies, but also the establishment of the correlative trade standard.  相似文献   

Multi-scale wavelet analysis of TOPEX/Poseidon altimeter significant wave height in eastern China seas     

郭衍游侯一筠  李明悝 《中国海洋湖沼学报》2006,24(1):81-86

The multi-scale characteristics of wave significant height (Hss) in eastern China seas were revealed by multi-scale wavelet analysis. In order to understand the relation between wave and wind, the TOPEX/Poseidon measurements of Hs and wind speed were analyzed. The result showed that Hs and wind speed change in multi-scale at one-, two-month, half-, one- and two-year cycles. But in a larger time scale, the variations in Hs and wind speed are different. Hs has a five-year cycle similar to the cycle of ENSO variation, while the wind speed has no such cycle. In the time domain, the correlation between Hs and ENSO is unclear.  相似文献