江南造山带西南段宰便辉绿岩年代学、地球化学及其构造意义SCIEI北大核心CSCD

宰便地区位于江南造山带西南段,发育有一系列新元古代镁铁质-超镁铁质火成岩。然而,其成因与构造背景仍存在广泛争议。因此,本文选择江南造山带西南段宰便辉绿岩为研究对象,系统开展岩石学、地球化学、Nd-Hf同位素和锆石U-Pb年代学研究。研究结果表明,辉绿岩具有高Mg^(#)(50~69)、高Al_(2)O_(3)(13.94%~18.63%)、低钾(0.03%~0.33%)、低磷(0.04%~0.28%)特征,显示为低钾拉斑系列岩石特点。同时,岩石整体相对富集Th、U等大离子亲石元素,亏损Nb和Y等高场强元素,Eu具有微弱负异常特征。辉绿岩的Nb/Ta、Zr/Nb比值揭示了母岩浆在岩浆侵位过程中未发生地壳混染。3件样品的锆石U-Pb年龄分别为820.7±3.0Ma、821.1±9.2Ma和823.1±9.5Ma,表明岩浆侵位时代为新元古代早期。锆石ε_(Hf)(t)值介于-13.6~7.7之间,Hf的t_(DM2)值介于1214~2547Ma之间,结合全岩地球化学特征,揭示其原始岩浆可能源于富集地幔,并伴有一定的亏损地幔参与。综合前人和本次研究的地质、地球化学和年代学数据,本文认为江南造山带西南段宰便地区在新元古代早期处于板内构造环境。     

当中国“瓷”遇到波斯“蓝”

<正>伊斯坦布尔托普座辉煌建筑。这座建筑自1465卡帕老皇宫位年至1853年间一直都是奥斯曼于伊斯坦布尔帝国苏丹在城内的官邸及主要居欧洲老城区东所,更是昔日举行国家仪式的场侧的萨拉基里所。宫殿前的大道上经常游人如奥角,是博斯普鲁斯海峡与金角织,来自各国的游客慕名而来,湾及马尔马拉海的交汇点上的一希望从这一进又一进的庭院中找     

Guadalupian （Middle Permian） Conodont Faunas at Shangsi Section, Northeast Sichuan Province

This study recovered the Guadalupian conodont faunas from Shangsi (上寺) Section in Northeast Sichuan (四川). Four genera and nine species were identified, and three conodont zones were recognized and established; they include Jinogondolella nankingensis Zone, J. aserrata Zone, and J. postserrata Zone. The Roadian and Wordian boundary is set in the interval 5 m from the top of Bed 86 by the first appearance of the conodont J. aserrata. The Wordian and Capitanian boundary is set in the interval 2.3 m from the top of the Bed 95 by the first appearance of J. postserrata. Most of the specimens demonstrated low color alteration index (CAI) as 1.5-3, indicating that most part of the Maokou (茅口) Formation may have the suitable thermal conditions for the formation of oil source rocks.     

渗透作用下滑带细观结构演变特性

库岸滑坡受到库水升降作用影响, 内部渗透压力会产生周期性的变化。动态渗透压力会导致滑带结构与强度产生劣化, 进而影响滑坡整体稳定性。为揭示滑带在渗透作用下的结构演变特征, 通过室内渗流试验结合CT扫描技术获取了黄土坡滑坡滑带在不同渗流条件下的细观结构特征, 采用Avizo软件量化滑带细观结构参数, 定量分析了不同渗透条件下滑带结构的演变规律。结果表明, 滑带的渗透系数随渗流时长的增加而呈指数形式下降, 且水力梯度越大最终试样的渗透系数越小; 连续的CT重构图像显示渗流过程中部分黏土团聚体发生解体, 大孔隙被附近的细颗粒逐渐充填, 试样结构的宏观均一性增强; 统计数据表明滑带土的表观孔隙率由5%下降到了1%, 等效直径小于80 μm的孔隙占比随渗流时长的增加而增多, 而等效直径大于80 μm的孔隙占比随渗流时长的增加而减少。结果证明周期性渗透作用会影响滑带内孔隙结构的分布特征, 细观上表现为大孔隙被小颗粒充填, 导致渗流通道变得细长而弯曲, 孔隙的有效连通性被削弱, 宏观上表现为渗透系数随渗流时长的增加而降低。      

城市供水管网抗震能力评价研究

供水管网是城市重要的基础设施,为了高效合理地评估现有供水管网的抗震能力,本文从结构安全性角度出发,构建了供水管网综合抗震能力评价指标体系和供水管网综合抗震能力评价模型。综合分析管道各项指标,运用主成分分析法得到指标权重并建立供水管道抗震能力模型,基于图论理论构建了供水管网基础抗震能力评价模型。从物理、社会和时间效应三个维度出发,将管网基础抗震能力通过环境评价修正系数进行修正,构建了精细化的供水管网综合抗震能力评价模型,以此表征管网的易损性,为地震灾害风险评估工作提供支持。通过对深圳市供水管网进行抗震能力评价,将结果与传统震害预测结果对比,说明了评价模型的合理性。     

海床基自动监测系统中央控制单元设计与实验

根据海洋监测仪器及系统工作环境的特点,需要从高可靠性、低功耗、长时间工作、小体积、轻重量等几个方面进行深入分析和研究。论文设计的海床基自动监测系统的中央控制单元,采用工业MSP430、带中断输出的时钟芯片DS1305、FLASH RAM和低阈值VMOS功率管等低功耗3.3 V器件,应用中断和休眠软件设计方法,很好地满足了使用要求。通过实验和分析,指出了低功耗海洋监测仪器及系统设计的基本原则,总结了MSP430闲置的管脚处理、上拉电阻阻值合理选择和电池自放电电流等问题的解决方案和应用经验。     

山东七宝山隐爆角砾岩型金铜矿床含矿蚀变斑岩石英颗粒中高温高盐度沸腾包裹体的发现及其意义

山东七宝山隐爆角砾岩型金铜矿床一直以来被认为是浅成低温、低盐度热液型矿床。本研究通过对该矿床含矿蚀变斑岩石英颗粒中流体包裹体的研究,发现存在大量多相包裹体与气体包裹体、气液两相包裹体共生。显微测温显示这些包裹体具有相似的均一温度(374～404℃),盐度高达48%NaCleqv。激光拉曼光谱和扫描电镜能谱分析显示,多相包裹体中的子矿物除了石盐外,还有赤铁矿、重晶石、黄铜矿与黄铁矿等。这些捕获有高温高盐度沸腾包裹体的石英颗粒可能是早期成矿流体在硅化交代蚀变的过程中重结晶形成的,而不是斑岩体的斑晶。这一结果表明该矿床深部存在高温、高盐度的沸腾包裹体。这种高温高盐度的沸腾流体包裹体及多相包裹体中黄铜矿、黄铁矿等子矿物是斑岩型矿床的典型特征,因此该发现表明山东七宝山隐爆角砾岩型金铜矿在深部可能转变为斑岩型矿床。     

Molecular Records of Primary Producers and Sedimentary Environmental Conditions of Late Permian Rocks in Northeast Sichuan, China

A series of biomarkers were identified in the aliphatic and aromatic fractions of the extracts from Late Permian Dalong (大隆) and Wujiaping (吴家坪) formations in Shangsi (上寺) Section, Northeast Sichuan (四川), South China, on the basis of the analysis of gas chromatography-mass spectrometry (GC-MC). The dominance of lower-molecular-weight n-alkanes throughout the profile suggests the dominant contribution of algae and bacteria to the organics preserved in the marine section. Wujiaping Formation is characterized by the elevated contribution from algae as well as other photoantotrophs such as photosynthetic bacteria as shown by the molecular ratios of hopanes to steranes or tricyclic terpanes as well as the ratio of pristane (Pr) and phytane (Ph) to C17 and C18 n-alkanes. This is in accord with the data from the microscopic measurement on the calcareous algae. In contrast, Dalong Formation is featured by enhanced contribution from bacteria and probably terrestrial organics indicated by the enhanced C24 tetracyclic terpanes relative to tricyclic terpanes. The two formations also show a distinct discrimination in sedimentary environmental conditions including redox condition and salinity. The anoxic condition was only found in the middle of the Dalong Formation as shown by the ratios of Pr/Ph and dibenzothiophene to phenanthrene, consistent with the reported data of Mo and U. An enhancedsalinity indicated by the homohopane index is observed at the shallow Wujiaping Formation. On the basis of the composition of primary productivity and the redox condition, Dalong Formation is proposed, herein, to be potential hydrocarbon source rocks in the study site. It is notable that the topmost end-Permian is characterized by a large perturbance in both the redox condition and salinity, with oxic conditions being frequently interrupted by short-term anoxia, likely showing a causal relationship with the episodic biotic crisis across the Permian-Triassic boundary.     

湘东北杨山庄金矿床流体成矿机制

杨山庄金矿床位于江南造山带中部,矿体严格受NW-NWW向断裂控制,赋存于新元古代浅变质的绢云母板岩和粉砂质板岩中,成矿期分为三个阶段:石英-毒砂-黄铁矿(少量)-自然金-白钨矿-白云石-白云母(阶段Ⅰ)、石英-毒砂-黄铁矿-自然金-黄铜矿-方铅矿-闪锌矿-绢云母(阶段Ⅱ)和石英-方解石(阶段Ⅲ)。成矿Ⅰ、Ⅱ阶段流体包裹体以两相水溶液包裹体为主,含有少量的气相包裹体和含CO_2的三相包裹体,气相包裹体成分为CH_4-N_2-CO_2、N_2-CO_2和N_2。成矿温度集中在240~320℃,盐度集中在7%~9%Na Cleqv,成矿流体为中-低温、中低盐度H_2O-Na Cl-CO_2体系。在成矿Ⅰ、Ⅱ阶段,成矿流体与围岩发生交代反应,流体发生相分离,使液相CO_2含量降低,引起Au(HS)~(2-)溶解度降低,导致金发生沉淀。