西藏罗布真矿区林子宗群火山岩锆石U-Pb年龄、地球化学特征及其地质意义     

赵亚云  杨春四  吕金梁  刘晓峰  刘波  郑常云  刘远超  李莉  付海龙 《现代地质》2019,33(1):73-84

罗布真铅锌多金属矿床位于冈底斯火山-岩浆活动带的中南部,矿区内广泛发育林子宗群火山岩,岩性为英安岩和流纹质晶屑凝灰岩。LA-ICP-MS锆石U-Pb定年结果显示,罗布真矿区内林子宗群英安岩的成岩年龄为(49.14±0.86) Ma,应属于帕那组火山岩地层,并非前人所认为的典中组。岩石具有高K、低Ti的特征,属于高钾钙碱系列;相对富集Rb、Th、U、K、Zr、Hf等元素,亏损Nb、Ta、P、Ti、Sr等元素,且轻重稀土分馏明显,具有明显的负铕(δEu=0.50~0.65)异常。在印度-亚洲大陆汇聚的过程中,新特提斯洋向欧亚大陆俯冲,约50 Ma发生了大规模的火山、岩浆作用,同时岩浆-热液成矿作用也进入高峰期,林子宗群火山岩的形成时代与该时代一致,形成于陆陆碰撞形成的板内环境。罗布真矿区林子宗群火山岩年龄的厘定,揭示了冈底斯带林子宗群帕那组火山岩具有赋矿潜力,对认识该地区林子宗群火山岩与热液脉型铅锌多金属矿化的关系具有指导意义。  相似文献   

UML在研建地理信息标准体系中的应用     

朱秀丽  李莉 《测绘通报》2012,(4):33-37

采用统一建模语言(unified modeling language,UML),对地理信息标准体系中标准间复杂的关系作了结构化分析,使得地理信息标准体系具有科学性、系统性和可扩展性。  相似文献   

读者来信     

李莉 《测绘通报》2012,(4):106

《测绘通报》编辑部：最近看到在贵刊2011年第12期刊登的《建立新国家地理格网服务地理国情监测初探》一文。文中第二部分＂国内外地理格网现状＂中提到：＂我国现行的《地理格网》标准规定的编码规则,因和投影分带有关,  相似文献   

历史时期中国重大自然灾害时空分异特征(英文)   总被引：4，自引：0，他引：4  

刘毅  杨宇  李莉 《地理学报(英文版)》2012,22(6):963-976

Based on historical documents and records this paper analyzes the characteristics of frequency and distribution of major disasters that took place in the history of China. The findings show that occurrences of different types of disasters varied and spatial pattern at provincial level are significantly different as well. The results also indicate that there is a strong relationship between type of disasters and spatial distribution and that the spatial pattern of losses was not the same as that of the frequency. The reasons are: (1) the hazard-formative environments which, to a large extent, determine the spatial pattern of the disasters are significantly different; (2) the losses caused by natural disasters were closely related to the concentration of economy and population. Number of deaths was usually large in areas where agriculture, culture and business were relatively developed. The spatial pattern of disaster losses is an evitable result of uneven economic development in the history of China.  相似文献   

羌塘东部治多县索加一带甲丕拉组火山岩特征及其构造环境     

李莉  白云山  马丽艳  牛志军  段其发 《华北地质》2009,32(1)

羌塘东部治多县索加南一带在大地构造上属东特提斯构造域,处于金沙江缝合带与龙木错-澜沧江缝合带之间的昌都地块中部,广泛分布以海相为主的晚三叠世地层.其中的甲丕拉组火山岩主要由碱性玄武岩、粗面安山岩组成的一套中基性岩石,岩石化学表现为表现为低TiO2(<1%),高Al,稀土元素特征表现为轻稀土元素富集.在微量元素地球化学方面,表现为富集大离子亲石元素,亏损高场强元素,εNo(t)变化在-2.2～-2.4之间,εSr(t)变化在42.6～53.4之间,表现为弧火山岩特征.据此认为该火山岩是拉竹龙-金沙江洋盆(或甘孜-理塘洋)向南消减的产物.  相似文献   

南海东北部冷泉区沉积物中有机质来源的生物标志物分析与环境指示意义   总被引：2，自引：2，他引：0  

丁玲  赵美训  于蒙  李莉  黄琦瑜 《海洋学报(英文版)》2017,36(10):8-19

Multi-biomarker indexes were analyzed for two piston cores from potential cold seep areas of the South China Sea off southwestern Taiwan. Total organic carbon(TOC) normalized terrestrial(n-alkanes) and marine(brassicasterol, dinosterol, alkenones and iso-GDGTs) biomarker contents and ratios(TMBR, 1/Pmar-aq, BIT) were used to evaluate the contributions of terrestrial and marine organic matter(TOM and MOM respectively) to the sedimentary organic matter, indicating that MOM dominated the organic sources in Core MD052911 and the sedimentary organic matter in Core ORI-_(86)0-22 was mainly derived from terrestrial inputs, and different morphologies were the likely reason for TOM percentage differences. BIT results suggested that river-transported terrestrial soil organic matter was not a major source of TOM of sedimentary organic matter around these settings.Diagnostic biomarkers for methane-oxidizing archaea(MOA) were only detected in one sample at 172 cm depth of Core ORI-_(86)0-22, with abnormally high iso-GDGTs content and Methane Index(MI) value(0.94). These results indicated high anaerobic oxidation of methane(AOM) activities at or around 172 cm in Core ORI-_(86)0-22.However in Core MD052911, MOA biomarkers were not detected and MI values were lower(0.19–0.38), indicated insignificant contributions of iso-GDGTs from methanotrophic archaea and the absence of significant AOM activities. Biomarker results thus indicated that the discontinuous upward methane seepage and insufficient methane flux could not induce high AOM activities in our sampling sites. In addition, the different patterns of TEX_(86) and U_(37)~(K′) temperature in two cores suggested that AOM activities affected TEX_(86)37 temperature estimates with lower values in Core ORI-_(86)0-22, but not significantly on TEX_(86) temperature estimates in Core MD052911.  相似文献   

北京区域2013严重灰霾污染的主被动遥感监测   总被引：4，自引：2，他引：2  

李正强  许华  张莹  张玉环  陈澄  李东辉  李莉  侯伟真  吕阳  顾行发 《遥感学报》2013,17(4):919-928

灰霾造成的严重大气污染受到人们越来越多的重视。结合2013年1月北京严重灰霾污染事件,介绍了太阳-天空辐射计、激光雷达、多波段CCD相机等遥感监测手段,分析了地-空基、主-被动等遥感方法获得的灰霾气溶胶特性遥感结果,讨论了不同遥感监测手段的特点及联合使用,结果表明：主动遥感手段在严重污染、夜间等情况下具有观测优势,而被动遥感信息含量大,具有获得气溶胶复杂特性参数的能力;地面遥感点、垂直分布线监测数据与卫星遥感的面观测数据相结合,可以初步实现灰霾的主被动遥感立体监测。  相似文献   

宁夏固原炭山窑山组形成时代的裂变径迹热史约束     

宋立军  牟秋环  李爱荣  李莉 《煤田地质与勘探》2013,(4):1-4

查明鄂尔多斯盆地西缘窑山组的形成时代,是正确进行地层对比、恢复盆地原貌及其演化的关键。根据"随着沉积作用的进行,窑山组埋藏深度增加,其经历的温度相应增加"的原理,运用磷灰石裂变径迹热史模拟方法,重建了宁夏固原炭山窑山组样品经历的温度史。热史模拟结果表明,样品初始埋藏增温的时间是距今196 Ma,样品埋藏增温的时间区间距今196-168 Ma。从而可知,炭山窑山组样品形成于距今196 Ma,窑山组形成于早-中侏罗世延安期(距今196-168 Ma)。  相似文献   

靖安油田张渠二区长2₁储层特征研究     

魏涛  朱玉双  李莉  温柔  孙亚君 《地下水》2013,(3):139-141

通过岩心观察,铸体薄片、扫描电镜和测井分析等各种资料对靖安油田张渠二区长21储层特征及影响因素进行综合分析。结果认为:研究区储层岩性主要为细-中粒长石砂岩。储集空间以粒间孔为主,溶孔次之。孔隙结构以中孔中喉型为主,进汞曲线平台较明显,储层物性相对较好,属中孔、低渗油藏。储层特征主要受沉积作用和成岩作用的综合影响。  相似文献   

广西平垌岭地区钨矿床成矿地质条件分析     

刘运锷  刘伟  李莉  陶明荣 《矿产与地质》2012,26(2):123-125

平垌岭地区位于江南台背斜的西南端,为广西山字型构造系脊柱部分。沿区域性龙岸-元宝山大断裂由南向北分布有平垌岭一个大中型石英细脉带及大脉型钨矿床及雨累、九结、思英口、洞榕山等小型矿床(点),并构成了一小型钨矿田。  相似文献