康定杂岩时代及成因探讨

康定杂岩是康滇地轴上一套复杂岩系，由紫苏辉长质暗色杂岩、英云闪长质浅色杂岩及复成分混合杂岩构成。岩石结构构构造，铀、钍及稀土特表明，主体为岩浆杂岩，包含大量具层状痕迹的变质杂岩。大量的锆石Ｕ－Ｐｂ年龄及其它同位素年龄表明，岩浆岩属晋宁－澄江期。变质杂岩时代与河口群相当。     

西藏高原大地电磁深探测———亚东—巴木错沿线地区壳幔电性结构

摘 要　 展示了超宽频带大地电磁深探测所获得的西藏亚东—巴木错沿线地区电性结构图像; 阐述了西藏中、南部特殊的壳幔电性特征。     

断裂带热释光的初步研究

本文对湖南水口山矿田断裂带岩石进行了热释光分析,断裂作用可对岩石的热释光特征产生显著变化。断裂带岩石天然热释光不存在250℃以下的低温峰;从围岩到断裂带中心,热释光峰值大幅度增加;同一断裂带从地表向深部热释光峰值增加。碎裂断裂带天然热释光峰值为10~3—10~4级,高峰温度位于290—310℃范围内;硅化断裂带的天然热释光峰值大多为10~2—10~3级,高峰温度多在330—350℃范围内。     

Geogene Versus Anthropogene Origin of Trace Metals in Sediments in Cua Luc Estuary and Ha Long Bay, Vietnam

In the present study, the geochemistry of 49 surficial-bed and 101 core sediment samples is investigated to clarify the origin of trace metals in the Cua Luc Estuary and Ha Long Bay, which is a famous World Natural Heritage Site in Vietnam. Moreover, the potential mobility of trace metals is also assessed and their relationship with reference elements (Al, Fe, and Ca) and organic matter is established in order to make recommendations for sediment management and monitor future pollution. Generally, trace metals display higher concentrations in Ha Long Bay compared to the Cua Luc Estuary. However, this is controlled by the distribution of the fine (clay?+?silt) fraction, and hence the concentrations of Al, Fe, Ca, and organic matter (OM). The comparison of concentrations of trace metals (normalized towards Al) between the surficial sediments and the subsurface core sediments based on ¹³⁷Cs datings indicates that almost all surficial-sediment data fall inside or deviate slightly from the 95 % prediction interval of a background regression line. In addition, as determined by a Community Bureau of Reference three-step extraction, trace metals mainly dominate in the residual fraction (assumed to relate to crystal lattice of primary and secondary minerals), and this fraction does not change much in recent sediment layers. Therefore, trace metals are supposed to be derived from natural bio/geochemical processes and are characterized by a low potential mobility. Consequently, the established linear regression relationships of trace metal vs. Al or multiple regression relationships of trace metal vs. multi-elements (Al, Fe, Ca, and OM) are useful for the prediction of background levels of trace metals in sediments in future pollution monitoring and assessment programs.     

Geochemistry of Brines from Salt Ore Deposits in Western Tarim Basin

In the geological evolution of the Tarim Basin, many transgressions and relictions happened. So there have been plentiful sources of salt. Moreover, because of uttermost drought, a lot of salt has been deposited. It is possible to find potash salt in this area. In our fieldwork, we have found salt and brine in western Tarim Basin. Based on a geological survey and the characteristics of sedimentary facies and paleogeography, this paper deals with the geochemical parameters and discusses the possibility of formation of potash salt in terms of the chemical analyses of samples collected from western Tarim Basin. Results of brine analysis lead to some conclusions: most of these salt brines have eluviated from very thick halite beds, mainly chloridetype salt and this kind of halite does not reach the stage of potash deposition in all aspects; WKSL (Wukeshalu) occupies a noticeable place, and we should attach importance to this district because there have been some indicators of the occurrence of potash deposits as viewed from the contents of Br and K. Finally, low Br contents are recognized in the Tarim Basin as a result of salt aggradation, and this point of view has been proved by the results of this experiment and the data available. It cannot depend upon the index of Br to judge the evolution stage of halite. We must look for other facies of potash except marine facies.     

加强工程施工项目管理措施与建议

结合项目施工管理的经验,从建立项目管理班子、项目评估和合同评审签订、人力资源的优化配置、强化劳务管理、责任成本管理、建立激励约束机制六个方面来探讨加强工程项目管理办法,并同时提出了加强工程项目管理的具体措施与建议.     

Effect of loading duration on uncertainty in creep analysis of clay

Some studies suggest that creep parameters should be determined using a greater quantity of creep test data to provide more reliable prediction regarding the deformation of soft soils. This study aims to investigate the effect of loading duration on model updating. One‐dimensional consolidation data of intact Vanttila clay under different loading durations collected from the literature is used for demonstration. The Bayesian probabilistic method is used to identify all unknown parameters based on the consolidation data during the entire consolidation process, and their uncertainty can be quantified through the obtained posterior probability density functions. Additionally, the optimal models are also determined from among 9 model candidates. The analyses indicate that the optimal models can describe the creep behavior of intact soft soils under different loading durations, and the adopted method can evaluate the effect of loading duration on uncertainty in the creep analysis. The uncertainty of a specific model and its model parameters decreases as more creep data are involved in the updating process, and the updated models that use more creep data can better capture the deformation behavior of an intact sample. The proposed method can provide quantified uncertainty in the process of model updating and assist engineers to decide whether the creep test data are sufficient for the creep analysis.     

黔东北地区铁丝坳组—大塘坡组细粒沉积岩高精度层序地层特征和充填演化模式

南华系大塘坡组是一套优质烃源岩和潜在非常规油气储层,具有重要的地史研究和油气勘探意义,然而关于其沉积过程及高精度层序地层方面的研究还较为薄弱。作者以黔东北ZK513井岩心描述及薄片观察为主要研究手段,运用了新的细粒沉积物的分类标准,精细划分识别了以石英砂岩、含砾泥质砂岩、灰色泥岩、灰色含砾砂质泥岩、灰色泥质砂岩、黑色炭质–硅质砂质泥岩、黑色含砾炭质–硅质泥质砂岩、灰色石英砂岩、黑色锰质泥岩、黑色泥质粉砂岩、黑灰色泥质粉砂岩、灰黑色泥质粉砂岩、灰色粉砂质泥岩、灰白色泥岩为代表的14种岩相。并根据岩相组合特征识别了陆棚内盆地、深水陆棚、浅水陆棚3种沉积相,以及前滨、冰海浅水陆棚、陆棚内富锰盆地、陆棚内深水盆地、陆棚内盆地边缘、深水陆棚、浅水陆棚7种沉积亚相。据岩相、沉积相分析,认为陆棚内盆地相内LF9黑色锰质泥岩、LF10黑色泥质粉砂岩为烃源岩的有利相区和层段。通过对岩相、沉积相的研究,识别出5个三级层序SQ1—SQ5,以及4个三级层序界面SB1—SB4;在三级层序内部,根据岩相叠加样式并结合沉积构造定量化统计,总结出4种典型的准层序类型,根据准层序的叠加形式识别了三级层序内部若干准层序组,进而识别出5个海侵(TST)—高位(HST)体系域旋回及内部的5次最大海泛面MFS1—MFS5,进而建立单井层序地层格架。综合ZK513井和研究区其他井岩相、沉积相、层序等资料,通过连井对比,建立了黔东北大塘坡组一段沉积期充填演化模式,预测了研究区内有利相区陆棚内盆地的分布,以及相区内富有机质层段LF9—LF10的展布模式。

     

基于MAPGIS的地质矿产勘查项目信息管理系统

以MapGIS为平台,二次开发实现了地质矿产勘查项目信息管理系统,并建立了重庆市矿产地和勘查项目库。该系统利用GIS技术合理规划矿产资源勘查,信息化管理矿产开发项目,为制定可持续发展的矿产资源开发利用方案提供辅助决策。     

南京某深基坑边坡支护设计与施工

南京某深基坑周边环境较为复杂,地下水丰富,基坑开挖较深,最深处达13m。根据周边环境的情况和开挖的深度,采用了钻孔灌注桩和土钉锚杆相结合的支护形式。分析了该基坑施工的技术要点,通过监测结果,说明该支护方案是可行的。