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491.
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   
492.
浅覆软弱地层中小净距盾构隧道施工时,后行隧道施工显著影响先行隧道安全,但深埋情况下,由于地下岩土层的复杂性和不确定性,使得多线隧道施工时先行隧道的变形变得复杂。以上海硬X射线土建部分盾构隧道为背景,结合有限元数值模拟,分析了深埋小净距盾构隧道施工时的相互影响,并对不同的盾构参数进行了敏感性分析。研究表明:随着后行隧道的开挖,先行隧道管片的变形增量变化基本呈双峰特征。当采用左-右-中方式开挖时,管片变形增量呈一大一小双峰分布;而采用中-右-左方式时,管片竖向变形增量峰值的大小和方向相同,而水平变形增量的峰值相同,方向不同;随着浆液弹性模量的增加,管片竖向变形增量变化较大,水平变形增量基本不变;随着顶推力的增大,管片的变形也在相应地增大,并在支护应力比为0.6~0.7之间时达到稳定;地下水的存在对管片竖向变形有着一定的影响;通过对比2种开挖方式管片的变形收敛情况,选择左-右-中次序开挖比较安全。  相似文献   
493.
鄂尔多斯盆地西缘处在阿拉善地块、鄂尔多斯地块及北祁连褶皱带之间的特殊构造位置,因而也是构造-沉积演化特征明显不同于盆地本部的一个复杂构造区。本文试图在西缘南段与盆地本部沉积演化特征对比分析的基础上,结合构造演化与古生界天然气成藏关系的研究,评价优选西缘南段古生界天然气成藏的有利区带和目标。主要形成以下几方面的认识:1)相对盆地本部而言,西缘南段早古生代沉积结束的晚、晚古生代沉积开始的早,表现出拉张、裂陷为主的早期构造活动特征,形成上、下古生界两套有利的成藏组合;中生代(尤其是侏罗纪)以来,则由于受冲断推覆构造活动的影响,西缘南段侏罗系及其后续构造层系的地层厚度在横向上变化较大,各构造层系的厚度差异可达千余米以上;2)西缘南段在大规模冲断推覆构造前即已基本成藏,燕山中-晚期以来的强烈冲断推覆构造,使部分地区古生界地层抬升剥露至近地表附近,导致古生界先成气藏遭受大面积破坏;3)在推覆体系的宽缓向斜区、以及主冲断层下盘的原地岩体中,古生界地层保存相对完整,受断裂破坏程度低,仍具有相对较好的保存条件;4)综合分析认为石沟驿向斜、韦州向斜、红寺堡向斜及银洞子向斜等4个宽缓向斜构造区的上古生界,以及处在惠安堡-沙井子主冲断层下盘原地岩体中的奥陶系台缘相带,是西缘南段古生界岩性圈闭气藏勘探的有利目标。  相似文献   
494.
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   
495.
何鹏  郭硕  张天福  苏航  付启龙 《岩石学报》2018,34(12):3597-3610
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   
496.
陈小月 《江苏地质》2018,42(2):222-227
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   
497.
周玉  龚大兴  周雄  周家云  岳相元 《地质通报》2018,37(10):1853-1865
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   
498.
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   
499.
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   
500.
代洪波  赵誉 《探矿工程》2012,39(1):80-84
结合南京长江隧道管片预制生产实例,介绍了大卣径盾构隧道管片预制生产技术,总结了高强度和高抗渗性管片预制生产技术控制措施,埘类似工程施工具有指导意义。  相似文献   
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