苏州轨道交通盾构隧道施工与运营期BOFDA监测技术研究

盾构隧道越来越广泛的应用于地下交通工程及地下管道构筑物中,其结构健康监测是保障隧道长期健康服役和反馈隧道安全隐患的重要课题。布里渊光频域分析技术（Brillouin Optical Frequency Domain Analyzer,BOFDA）是近年来国际上发展起来的分布式光纤传感新技术,并开始应用于岩土体内部变形的监测。本文依托苏州轨道交通盾构隧道结构健康监测项目,将基于BOFDA的分布式光纤感测技术应用于盾构隧道施工和运营期的结构安全健康监测。作者设计了可行的监测方案,研发了合理的光纤传感器及配套夹具,对隧道环向收敛、纵向沉降以及伸缩缝的变形进行了监测,取得了一批反映盾构隧道施工和运营期的结构安全健康监测数据,并对隧道的健康状态进行了分析。监测结果表明：BOFDA技术可有效地对隧道结构变形异常点、渗漏点和管片错动处等准确定位和监测,具有分布式、长距离、耐腐蚀、成活率高等技术优势,是地铁盾构隧道施工和运营期结构健康监测的一种十分有效的新手段。     

新疆阿合奇地区晚石炭世—早二叠世蜓类动物群

在塔里木盆地西北缘的阿合奇地区晚石炭世—早二叠世地层中发现大量的 类化石,共计18属61种,另有较多未定种,自下而上建立了4个 带,依次为Pseudostaffella带、Profusulinella带、Fusulinella-Fusulina带和Pseudoschwagerina带。各 带与华南、帕米尔达尔瓦兹等地能很好的对比,且蜓类动物群面貌与华南地区相似 。根据蜓类化石确定别根他乌组为晚石炭世早中期罗苏期—达拉期,康克林组为晚石炭世晚期小独山期—早二叠世紫松期,将该区石炭系、二叠系的界线置于71层底部。石炭纪末期区域上海退和古地形的影响导致蜓带Triticites带的缺失。     

西南三江甭哥金矿床磷灰石地球化学特征及地质意义

甭哥金矿床位于西南三江造山带北段的义敦弧南缘,属于与富碱侵入岩有关的金矿床。目前,对其成矿机理认识仍较为薄弱,制约了资源评价和找矿勘查进展。本文选取甭哥金矿床强矿化的正长斑岩和弱矿化的黑云辉石正长岩中的磷灰石作为研究对象,详细剖析磷灰石的地球化学特征,探讨其记录的成岩成矿信息。结果表明,磷灰石的稀土元素含量特征及配分模式显示富碱岩浆主要来自于壳幔混合的源区,黑云辉石正长岩中磷灰石的(La/Sm)N、(La/Yb)N、(Sm/Yb)N值和Sr含量呈正相关,说明长石结晶对岩浆结晶分异有重要的影响;正长斑岩中磷灰石具有高Sr/Y、Ce/Pb值,而Th/U、(Sm/Yb)N值较低,指示强烈的流体活动参与了岩浆结晶过程;磷灰石挥发分(F、Cl)含量及比值特征指示金矿成矿流体主要来自地幔源区,成矿与富碱、高氯的成矿流体有关。磷灰石Mn氧逸度计估算结果显示,甭哥富碱侵入岩具有高氧逸度特性,但两种不同岩性岩石的氧逸度具有差异性。其中,正长斑岩的logf_(O_2)值为-12～-10. 3,黑云辉石正长岩的logf_(O_2)值为-15. 5～-11. 1,磷灰石中SO_3含量及Ga含量也暗示正长斑岩的氧逸度高于黑云辉石正长岩的特征;结合磷灰石低Mn、Ga含量和高的Cl、SO_3含量,反映甭哥金矿床金的成矿是在高氧逸度条件下金氯络合物迁移、富集而沉淀的结果。因而,磷灰石的地球化学特征对金矿床成矿过程示踪和勘查评价具有重要的指示意义。     

新疆富蕴县北部金格岩体斜长花岗岩LA-ICP-MS锆石U-Pb年龄及其地质意义

对新疆富蕴县北部金格岩体斜长花岗岩进行LA-ICP-MS锆石U-Pb年龄测定,获得了402.7±2.9Ma(MSWD=0.17)的岩浆结晶年龄,表明岩体形成时代为早泥盆世。金格岩体岩性组合为英云闪长岩-奥长花岗岩-花岗闪长岩,具有TTG组合特征,暗示与洋俯冲作用有关。岩石地球化学具有高硅(SiO_2=72.55%～77.41%),富钠(Na_2O=4.94%～6.63%),贫钾(K_2O=0.24%～0.95%)的特征,Al_2O_3含量为12.11%～15.30%,铝饱和指数在0.94～1.04之间,呈低钾拉斑玄武岩系列、准铝质-弱过铝质、I型花岗岩的特征。稀土元素显示轻稀土元素富集、重稀土元素相对亏损,中等-弱负Eu异常的右倾型,微量元素Rb、Th、U等大离子亲石元素富集,呈明显的"峰",Nb、Ta、Ti等高场强元素强烈亏损,呈明显"TNT"负异常,显示了与俯冲作用有关的岩浆岩特征。结合区域地质资料,金格岩体形成于与洋俯冲作用有关的活动大陆边缘的陆弧环境,金格—正格河地区在早泥盆世处于局部拉张环境。     

Simulation Study on the Impact of Taihang Mountain Slopes on Downhill Front Cyclone Rainstorm

The statistical and diagnostic analysis of precipitation in Hebei Province in the past six years shows that the mid-south of the North China Plain on the east side of the Taihang Mountains is an area of frequent rainstorm disasters in summer. The rain belt is mostly distributed along the Taihang Mountains, and the rainfall is often over 700mm. Focus was on the summer downhill frontal Yellow River cyclone, which accounted for 20% of the 73 storm days in the statistical samples. The analysis of the typical frontal cyclone heavy rain in 2016 shows that the meridional distribution of the Taihang Mountains cooperates with the climbing mountain jet in the north of the cyclone and the southward flow in the west of the cyclone, leading to the formation of a deep narrow cold temperature trough along the mountain orientation. It enhances the temperature gradient in the frontal cyclone, enhances the baroclinicity of the cyclone and the intensity of the rotating wind, resulting in augmentation of the cyclone and slowing of the eastward movement. Through the cooperation of the entanglement of the cyclone jet and the mountain block, a deep and abundant water vapor environment is formed, and the moving westward of water vapor flux and the low-level water vapor main body are hindered; The high-energy tongue convection instability on the eastern side of the mountain range is formed, a strong uplift with abundant water vapor masses is triggered, and three critical areas of vertical motion occurred, which restricts the rainstorm locations. Numerical experiments on the mechanism of the influence of the slope of the Taihang Mountains on heavy rain show that the downhill rainstorm area is parallel to the mountain range, and the meridional mountain range can cause a greater range of heavy precipitation. It is also easy to cause double frontal precipitation locally by a same cyclonic warm front and cold front, resulting in a long duration of heavy rain. The slope of the mountain is proportional to the intensity of the mountain block and forms the wet convection instability with the dry at lower and wet at upper overlapping on a thermal instability of the front zone with cold at lower and warm at upper, such as the total instability is stronger. The slope of the mountain is proportional to the increase and maintenance time of the cyclone decompression during downhill. It is inversely proportional to the decline to the North China Plain, which affects the path and speed of the cyclone eastward movement.     

利用曲率类属性预测储层裂缝的流程及应用实例

基于曲率类属性,本文提出预测"裂缝发育带—裂缝发育方向—开启裂缝"的一套流程,首先对地震数据体进行曲率运算预测裂缝型储层发育带;然后对曲率数据体计算玫瑰图属性,用成像测井的玫瑰图与曲率体计算的玫瑰图进行比对,从而确定裂缝的发育方向;根据裂缝发育方向优选2个主要裂缝发育的主方向,然后根据裂缝发育的主方向对曲率数据体计算2个主方向方位强度属性;将2个方位强度属性分别与产能交会,其中相关性较好的方位为裂缝的开启方位。上述方法在哈萨克K油田应用,预测了K油田区东部地区为缝洞型储层发育带,西部地区为裂缝型储层发育带;主要发育NE向和NW向两组裂缝,其中NE向裂缝北部地区开启性好,NW向裂缝南部地区开启性好;根据预测结果,提出的2口钻井获得了商业油流。     

高山峡谷地区高陡边坡深部裂缝一般特征分析

中国西南部,尤其是水能资源较为集中的青藏高原周边地区是近期工程建设的热点地区。由于强烈的内外动力地质作用,这些地区形成了高山耸立、沟谷深切的地貌景观,高山峡谷区的高陡岩质斜坡变形与稳定将是工程建设所面临的主要工程地质问题之一。高陡边坡的变形与稳定对工程建设的可行性起到决定性作用,并影响着施工周期和工程造价。本文分析了深裂缝现象的一般特征,认为深裂缝是在特定地质环境下内外动力地质共同作用的产物,一般均具有三高、继生这一共性。在工程处理方面,深裂缝可按山体加固的方法进行工程处理,预应力锚固洞可较好处理深裂缝问题。     

Al2O3改良红黏土的力学试验研究

广西是我国铝业的生产大省,在生产金属铝的时候会产生污染物赤泥,由于赤泥结合的化学碱难以脱除,对地下水污染严重,大量的赤泥堆放,不仅占用了大片的土地,干燥的赤泥还会造成粉尘污染,有效地对赤泥进行回收利用已经成为当前迫在眉睫的任务。本次研究尝试使用作为赤泥主要成分之一的Al2O3的掺入,研究其对红黏土的物理力学性质的影响,本次试验采用掺入率分别为0、1%、2%、3%、4%,5个不同掺入比例Al2O3后的红黏土。对其进行液塑性试验,分析不同掺入率的红黏土的液塑性变化情况。通过击实试验,得出不同掺入率下红黏土的最大干密度、最优含水率。最后对红黏土重塑样进行三轴不固结不排水剪切试验,获得在同一含水率,不同掺入率、不同围压下的应力-应变关系曲线、弹性模量、抗剪强度参数的变化规律。试验结果表明：改良后的红黏土还是具有高液、塑限的特性,其状态为坚硬。随着掺入的Al2O3的量增加,其液限、塑限、塑性指数、含水率、最大干密度都降低;同等Al2O3掺入量的情况下,随着围压的增大抗剪强度增强,在同等围压下,随着Al2O3掺入量的增加抗剪强度呈先降低后增高的状态。     

东昆中构造带沟里地区浅变质地层碎屑锆石UPb年龄及其地质意义

东昆中构造带具有复杂的物质组成与结构构造,其中沟里地区出露的原划石炭系浅变质沉积地层是东昆中蛇绿构造混杂岩基质岩系的重要组成部分,其形成时代和属性研究对东昆中构造带研究具有重要意义。运用LA-MC-ICP-MS锆石U-Pb年代学分析方法,对浅变质沉积地层变砂岩碎屑锆石进行详细研究,结果显示,碎屑锆石年龄谱可分为4组：①加里东期（499~565Ma）。②新元古代中期至早期（693~969Ma）。③古元古代晚期-中元古代中期（1 254~1 967Ma）。④新太古代-古元古代早期（2 348~2 776Ma）。结合前人研究资料认为浅变质沉积地层形成时间在427~499Ma,应归属于早古生代纳赤台岩群变沉积岩。其沉积物源以新元古代早期至中期响应Rodinia超大陆汇聚、裂解的物质记录及新太古代-元古代结晶基底为主,少量东昆仑地区加里东期与原特提斯洋扩张俯冲相关岩浆岩。东昆中构造带沟里地区基质地层主要是早古生代纳赤台岩群变沉积岩,而不是前人认为的石炭纪地层。东昆中构造带主要构造活动在早古生代末期就已经基本完成。     

Estimating groundwater recharge beneath irrigated farmland using environmental tracers fluoride, chloride and sulfate

Accurate recharge estimation is essential for effective groundwater management, especially in the North China Plain, where irrigation return flow is significant to vertical recharge but brings difficulty for recharge estimation. Three environmental tracers (F^?, Cl^? and SO₄ ^2?) were used to estimate vertical recharge based on the mass balance and cumulative methods. Four boreholes were dry-drilled to 5–25 m depth beneath irrigated farmland and one was drilled to 5 m beneath non-irrigated woodland; soil samples were collected in all boreholes at set depths. The results indicated that F^?, Cl^? and SO₄ ^2?were suitable tracers beneath the non-irrigated woodland, yielding recharge rates of 16.9, 18.8 and 19.4 mm/year, respectively. Recharge estimation was not straightforward when taking account of crop type, irrigation and/or fertilizer use. After comparing with previous research, conclusions were drawn: Cl^? was an appropriate tracer for irrigated farmland when taking account of Cl^? input from irrigation and absorption by crops; recharge rates were 65.9–126.8 mm/year. However, F^? was a more suitable tracer for irrigated regions where account is made of the proportion of precipitation to irrigation return flow, provided low F^? concentrations can be measured reliably.