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531.
532.
基于法平面的GIS平面随机线元概率算法 总被引:6,自引:1,他引:6
基于概率论与数值分析,研究基于线元法平面的GIS中平面随机线元落入其相应误差模型内的概率算法,通过实例计算与可视化分析,比较基于误差模型建模机理的概率算法,并得出如下结论:基于线元法平面的概率算法与基于误差模型建模机理的概率算法对GIS中随机线元误差模型的建模是等价的,而且对于GIS中一般曲线的误差模型建模而言,前者具有通用性。 相似文献
533.
笔者总结了近年来的研究成果认为.中国东部的郯庐断裂带白海西期以来经历了两个主要发展阶段:第一阶段是广义的郯庐断裂带发展阶段,晚三叠世-早侏罗世由于扬子地块与华北地块的碰撞,成为两地块的对接边界,具有逆冲推覆的性质,属广义的特提斯构造域。第二发展阶段从早白垩世以来,发展成为一条平移断裂带,属于狭义的环太平洋构造域的平移系统。岩相古地理资料显示了扬子地块与华北地块的对接始于晚二叠世早期:印支期的郯庐断裂带是一条由NE、NNE向展布的缓‘S’型的地块拼贴边界.在现今的郯庐断裂带上表现为残留的由北北西向南南东的斜向逆冲推覆的性质,中下构造层次表现为韧性逆冲推覆变形,上部构造层即前陆褶皱冲断带内的变形:应力场分析资料显示:早三叠世晚期开始地表浅部就有近南北向的挤压作用,左行走滑平移作用开始发育:早白垩世晚期开始转入引张伸展阶段.与中国东部的伸展作用一致:新近纪又转为近东西向挤压.发育逆冲兼右行走滑作用. 相似文献
534.
DU Xin ZHAO Xiaoguang 《地球空间信息科学学报》2007,10(1):33-36
A method based on local HSV image and the shape of object to recognize object is proposed for robot tracking. After the color segment, the knowledge of the shape of objects is used to recognize objects. The robot tracking result testifies the avail-ability of the method. 相似文献
535.
H. X. Wang S. R. Liu R. Chu B. Liu P. P. Shi 《Australian Journal of Earth Sciences》2018,65(5):711-725
This work focuses on quantitative discrimination of fault segment growth and its effect on sedimentation and stratigraphic evolution in the Tanan Depression, the Tamtsag Basin, Mongolia. Integrated seismic data sets and stratigraphic data suggest that normal faults evolve as fault segments grow, link and amalgamate to form a larger fault. Three main stages in the evolution of fault zone are recorded in the syn-rift stratigraphy. This paper applies a method to effectively discriminate the locus of fault segments by ‘three diagrams’ and quantitatively reconstruct process of fault growth by the maximum throw subtraction method. Backstripped to T23 SB event, the F1 fault comprises four hard-linked segments, and the F2 fault is divided into four soft-linked segments (F2-4 and F2-5 segments are shown by hard linkage) at the T23 structural level. The F1 and F2 fault comprise hard-linked segments at the T23-1 structural level when the F1 and the F2 are backstripped to the T22 (133.9 Ma) SB event. The F1 fault is divided into three soft-linked segments (F1-2 and F1-3 segments are shown by hard linkage), and the F2 fault is divided into four isolated fault segments at the T23-1 structural level when the F1 and the F2 is backstripped to the T23 SB event. Incorporation of paleo-fault geometry, isochron thickness map and sedimentary facies suggest that the transfer zone provided accommodation space for sediment discharge and deposition, and the depocentres were formed at the locus of maximum throw along a fault segment during its overall deposition. 相似文献
536.
大兴安岭中南段扎木钦铅锌银多金属矿床成矿物质来源及矿床成因:来自S、Pb同位素的制约 总被引:1,自引:1,他引:0
扎木钦铅锌银矿床位于内蒙古科尔沁右翼中旗,是近些年来在大兴安岭中南段地区新发现的一处大型多金属矿床。扎木钦矿床矿体主要呈脉状、透镜状、层状、似层状赋存于白音高老组中酸性火山岩中;根据矿石的结构、构造以及矿物之间的共生组合、穿切关系,划分出毒砂-黄铁矿阶段、铅锌金属硫化物阶段、银矿物阶段、石英-碳酸盐阶段四个主要成矿阶段。在对矿床成矿地质条件详细总结研究的基础上,为探讨扎木钦多金属矿床成矿物质来源及矿床成因,本文对矿床中主要金属硫化物开展了S、Pb同位素组成分析。硫同位素测试结果表明扎木钦矿床中δ~(34)S值为4. 4‰~5. 8‰,平均值为5. 05‰,数值均一,变化范围小,具有塔式分布特征,指示硫来源于深源岩浆。铅同位素测试结果为:~(206)Pb/~(204)Pb值为17. 761~18. 291,平均值为18. 130;~(207)Pb/~(204)Pb值为15. 509~15. 671,平均值为15. 593;~(208)Pb/~(204)Pb值为37. 800~38. 205,平均值为38. 032,上述结果显示其铅同位素组成稳定。μ值为9. 30~9. 69,ω值变化范围为34. 57~38. 15。各项分析数据及图解指示铅具有壳幔混合来源特征。扎木钦矿床硫铅同位素组成与大兴安岭地区成矿物质为岩浆来源的金属矿床特征极为相似,矿床成矿与早白垩世火山岩浆活动关系密切,是深部岩浆流体逐步演化的产物,矿床成因类型为陆相火山热液型铅锌银多金属矿床。 相似文献
537.
广从断裂带在金沙洲段以3条近平行的北东向分支断裂展布,钻孔岩芯及显微构造分析表明,研究区基岩受断裂活动影响无疑,且断裂活动时代较新。以金沙洲基岩之上普遍存在的土黄色-褐黄色粉砂质黏土(或黏土)标志层为样品进行粒度分析,所得粒度参数及概率累积曲线表明,该层沉积物可与珠江三角洲其他区域进行对比,为晚更新世晚期(10~20 ka B.P.)沉积,该地层之上灰黑色-黑色淤泥质层(或细砂层)出现了明显的全新世高海面沉积异常,淤泥层中腐木的~(14)C年龄为6~7 ka B.P.,确认广从断裂金沙洲段的最新活动年龄为6~7 ka B.P.。 相似文献
538.
为了解可可西里-松潘-甘孜地块西北缘的构造演化及侵入岩与区域浅成低温热液矿床成矿的关系,在野外地质调查的基础上,采集了东昆仑西段的卧龙岗岩体花岗斑岩样品,对其中的12件和2件样品分别进行了岩石地球化学及LA-ICP-MS锆石U-Pb年龄测定。结果表明,花岗斑岩SiO_2含量为64.96%~71.24%,高钾、富钠、贫钙。AR值为1.97~2.95,A/CNK值为0.98~1.16,为高钾钙碱性系列。岩石相对富集Cs、Rb、Ba、U和Nd,亏损Zr、Hf、Sr、Ti和Y。稀土元素总量为151×10~(-6)~239×10~(-6),LREE/HREE值为8.10~14.53,δEu为0.54~0.70,具有明显的负Eu异常。锆石~(206)Pb/~(238)U年龄分别为205.6±1.6Ma和204.7±2.6Ma,表明卧龙岗岩体形成于晚三叠世末期。综合分析认为,可可西里-松潘-甘孜地块西北缘在晚三叠世末期应处于后碰撞伸展构造背景,区域浅成低温热液矿床形成时代晚于晚三叠世末期。 相似文献
539.
The water quality in the surface microlayer (SML) and subsurface water (SSW) in the Guangzhou segment of Pearl River, a eutrophic urban river section in China, were analyzed. The spatial and temporal dynamics of nutrient concentrations, heavy metals and bacteria were examined from two sampling sites in monthly samples throughout 2010. The mean concentrations of total nitrogen, ammonia, nitrate and nitrite were higher than 7.0 mg/L, 3.1 mg/L, 1.1 mg/L and 0.3 mg/L, while total phosphorus and orthophosphate were 0.5 mg/L and 0.1 mg/L, respectively. These results indicated that the water quality was rich in minerals and eutrophic. The mean concentrations of Mn and Fe were higher than 0.013 mg/L; and Ni, Cr and Pb were higher than 0.001 mg/L. The mean concentrations were in the order of Mn >Fe > Ni > Pb > Cr. The concentrations of heavy metals in the Guangzhou segment were lower than the limit of the surface water quality standards in China and the World Health Organization (WHO), but higher than the median values in the world’s freshwater. The density of bacteria ranged from 3.30×105 to 5.23×106 cells/mL, and the amount of cultivable heterotrophic bacteria ranged from 1.30×103 to 1.89×106 cfu/mL. Fecal coliform levels were beyond the V class of China water quality standard. The SML was enriched in nutrients, heavy metals and bacteria, with the maximum enrichment factor of 3.84 for nutrients, 8.00 for heavy metals, and 3.04 for bacteria, suggesting that the water quality of the SML of the Guangzhou segment of the Pearl River was more serious than in the SSW. 相似文献
540.
珠江广州河段微表层与次表层水环境质量比较(英文) 总被引:1,自引:0,他引:1
The water quality in the surface microlayer(SML) and subsurface water(SSW) in the Guangzhou segment of Pearl River, a eutrophic urban river section in China, were analyzed. The spatial and temporal dynamics of nutrient concentrations, heavy metals and bacteria were examined from two sampling sites in monthly samples throughout 2010. The mean concentrations of total nitrogen, ammonia, nitrate and nitrite were higher than 7.0 mg/L, 3.1 mg/L, 1.1 mg/L and 0.3 mg/L, while total phosphorus and orthophosphate were 0.5 mg/L and 0.1 mg/L, respectively. These results indicated that the water quality was rich in minerals and eutrophic. The mean concentrations of Mn and Fe were higher than 0.013 mg/L; and Ni, Cr and Pb were higher than 0.001 mg/L. The mean concentrations were in the order of Mn Fe Ni Pb Cr. The concentrations of heavy metals in the Guangzhou segment were lower than the limit of the surface water quality standards in China and the World Health Organization(WHO), but higher than the median values in the world's freshwater. The density of bacteria ranged from 3.30×105 to 5.23×106 cells/mL, and the amount of cultivable heterotrophic bacteria ranged from 1.30×10 3 to 1.89×10 6 cfu/mL. Fecal coliform levels were beyond the V class of China water quality standard. The SML was enriched in nutrients, heavy metals and bacteria, with the maximum enrichment factor of 3.84 for nutrients, 8.00 for heavy metals, and 3.04 for bacteria, suggesting that the water quality of the SML of the Guangzhou segment of the Pearl River was more serious than in the SSW. 相似文献