利用X射线衍射和岩矿鉴定等技术研究河南汤家坪钼矿区主要矿物标型特征   总被引：1，自引：1，他引：0  

周姣花  汪建宇  顾茗心  王真 《岩矿测试》2015,34(1):82-90

汤家坪钼矿床是2006年探明的一处大型斑岩型钼矿床,前人用常规地质方法对该矿区基础地质工作和成矿规律研究已比较系统和完整,认为汤家坪钼矿床属于深源浅成斑岩型钼矿床,汤家坪花岗斑岩体为矿区钼矿的成矿母岩;但是没有从矿物学角度来应证这些成矿规律。本文从矿物学角度,采用分离单矿物进行化学分析、X射线衍射(XRD)及岩矿鉴定等技术,对汤家坪钼矿区的辉钼矿、黄铁矿、石英、长石4种矿物标型特征(化学组成、微量元素、晶体结构、晶胞参数、结构状态等)进行研究。结果表明:1该矿区辉钼矿全部是2H型多型变体,且成分中Re含量很低;辉钼矿的δ34S值为3.0‰,硫同位素变化范围小,接近于陨石硫,具深源硫的特点,硫来源于花岗斑岩。2黄铁矿微量元素以富含Mo、Co、Cu,贫Ni、Pb、Zn为标型特征,另外Au、Ag含量低,S/Se大于250000,与前人"S/Se大于250000~500000的地区不可能找到金矿"的结论相符。3石英富含Mo;成矿期石英脉中δ18O降低,表明成矿晚期有少量大气降水参与热液蚀变成矿。4长石富含Mo;轻稀土(La~Nd)含量大于中稀土(Sm~Ho)和重稀土(Er~Y)含量;钾长石的有序度、三斜度以及结构参数的值均较高,结构温度较低,表明该矿区钾长石为低温状态下的三斜对称的微斜长石,是热液作用的产物,岩体钾长石化对钼矿化最为有利。本研究应证了汤家坪钼矿床属于深源浅成斑岩型钼矿床,对于总结斑岩型钼矿成矿规律、找矿标志有重要意义。  相似文献   

井筒与油藏耦合的压裂水平井非稳态产能计算模型   总被引：1，自引：0，他引：1  

曾凡辉  郭建春  尹建 《现代地质》2011,25(6):1159-1166

为了准确预测压裂水平井的产量,综合考虑流体在储层、井壁、压裂裂缝、射孔孔眼以及水平井筒中的流动过程,根据势叠加原理,建立了考虑射孔孔眼、压裂裂缝生产干扰作用下的井筒、油藏耦合压裂水平井非稳态产能计算模型。结果表明:只考虑裂缝生产与裂缝、孔眼同时生产时的水平井产量在生产初期差别较大,生产后期差别变小;由于裂缝、孔眼的干扰,水平井筒两端裂缝的产量高于中间裂缝的产量;由于井筒摩阻作用,关于水平井筒中心对称的裂缝流量不相等;随着裂缝长度增加,裂缝、射孔孔眼、水平井产量增大;随着裂缝导流能力增加,裂缝产量增大,射孔孔眼产量降低,水平井产量增大;射孔段越长,孔眼与裂缝的干扰愈强,单个孔眼的产量降低,但由于射孔数增加,水平井产量增大;射孔深度增加,压裂水平井产量增加。  相似文献   

云南宣威-曲靖段高速公路遥感选线应用研究     

李聪聪  张光超  张培贤 《中国煤炭地质》2011,(7):56-60

在国家高速公路G56杭州至瑞丽公路宣威-曲靖段前期选线研究中,以日本ALOS卫星遥感图像为主要信息源,对其进行遥感数据处理。依据遥感解译结果,结合野外调查验证资料,对宣威-曲靖段进行了工程地质区划分与评价,确定地质灾害较易发区：滑坡区、地表岩溶塌陷区、隐伏岩溶区、煤矿采空塌陷区;依据公路工程评价因素,将工程区划分为4个工程地质区、9个工程地质亚区。通过对线路走廊带及主要工点工程地质条件的评价,对工程设计推荐线与三段局部比较线（C、D、E）方案进行优选,最终确定了在推存线方案中可考虑采用C、E局部方案的理想线路。  相似文献   

Stress state in the Cuu Long and Nam Con Son basins, offshore Vietnam     

Nguyen Thi Thanh Binh  Tomochika TokunagaNeil R. Goulty  Hoang Phuoc SonMai Van Binh 《Marine and Petroleum Geology》2011,28(5):973-979

The results presented in this paper are the first published estimates of the complete stress tensor in the Cuu Long and Nam Con Son basins, offshore Vietnam. We analysed in situ stress and pore pressure fields in the sedimentary formations using data from petroleum exploration and production wells to evaluate the stress state in these basins. The data were obtained from the seafloor to 4300 m burial depth and include both hydrostatic and overpressured sections. Minimum horizontal stresses were obtained from extended leak-off tests and mini-fracture tests. Maximum horizontal stresses were estimated from drilling-induced fracture parameters and borehole breakout widths in twelve wells using rock properties measured in the laboratory or estimated empirically from wireline logs. Seven data points are located in sediments, and seventeen data points in igneous basement rocks at depths greater than 3000 m.The estimated magnitudes of σ_H are 70-110% of the σ_v magnitudes. Considering the errors in the stress magnitude estimates, their relative magnitudes suggest that a borderline normal/strike-slip stress regime presently exists in normally pressured sequences of the Nam Con Son and Cuu Long basins. Of the twenty-four data points, twenty have effective stress ratios at a critical stress state for faulting on the assumption that there are faults present that are optimally oriented for failure with friction coefficients of ∼0.5. The results suggest that the stress state in these basins is generally critical.  相似文献   

AIS专题统计分析应用系统研究          下载免费PDF全文

赵忠东  夏启兵 《海洋测绘》2011,31(3):54-57

AIS专题统计分析应用系统以AIS岸基网络系统提供的信息为基础,采用分级、分类、定制等多种技术手段,实现AIS船舶运行信息的有效管理和共享,为航海及其他海洋活动提供更加全面、及时、可靠和集成的综合信息服务,进一步发挥AIS系统信息的社会服务效能.文章描述了系统的实现目标、系统组成、功能模块设计及关键技术,并对系统应用前...  相似文献   

砂质海滩地形动力分类研究进展     

于吉涛  陈子燊 《热带地理》2011,31(1):107-112

海滩状态是一个地形与水动力相互作用的三维地形动力问题.国外对海滩状态的地形动力分类已开展了大量卓有成效的研究工作,既包括波控、小潮、开阔海岸海滩状态的研究,也包括波控、不同潮差海岸海滩类型的研究和岬间海岸海滩类型的研究.文中回顾并概括了自20世纪70年代至今国外在砂质海滩地形动力分类方面代表性的研究工作,这些对于我国的...  相似文献   

铜陵地区不同景观区金属态地球化学特征     

赵华荣  杜建国  杨义忠  曹恒  李明辉 《安徽地质》2015,(1):42-48

通过铜陵地区已知矿集区和覆盖区多金属态测量,不仅确定了深穿透测量在矿集区的有效指示作用,同时,根据不同景观区、不同金属态地球化学特征的对比,指出了覆盖区具指示意义的元素金属态,为长江中下游平原区寻找隐伏矿床提出了新的化探方法。  相似文献   

微束分析技术在研究伴生金元素赋存状态中的应用   总被引：1，自引：1，他引：0  

戴婕  徐金沙  潘晓东  任静  张茜 《岩矿测试》2011,30(6):655-663

运用微束分析技术扫描电子显微镜(SEM)及其配套的背散射电子像功能,特征X射线线扫描、面扫描功能,能谱仪(EDAX)鉴定功能,观察里伍铜矿矿石中纳米级至微米级的伴生金(超微细金)矿物,获取其形貌照片、能谱图和定性定量分析结果,得到了清晰的金元素及与其共生的元素线、面分布图像,查明了里伍铜矿中的金元素是以类质同象的形式分布于含银的铋矿物和金银矿中,含银的铋矿物和金银矿分布在黄铜矿与磁黄铁矿的裂隙中及含锰的铁闪锌矿中,排除了基体成分的干扰,载金矿物颗粒至少大于20 nm。该方法操作简便,过程简单,分析结果直观、可靠,提高了研究伴生金元素赋存状态的效率。测试的样品为里伍铜矿热液型矿石,经分析形成于燕山中晚期(104～142.2 Ma),为局部构造运动和岩浆期后热液使成矿元素再富集成矿的地质产物,晚于主成矿期——燕山中期。里伍铜矿中Ag和Au的质量比值为1.38～4.59,推测伴生金的成矿温度应小于或等于227℃。里伍铜矿在成矿过程中至少经历了早期的中高温热液阶段和晚期的中低温热液阶段,早期大量硫化物的析出和晚期中低温绿泥石、绢云母矿物的大量出现也证实了这一过程的存在。  相似文献   

Fabric evolution within shear bands of granular materials and its relation to critical state theory   总被引：2，自引：0，他引：2  

Pengcheng Fu  Yannis F. Dafalias 《国际地质力学数值与分析法杂志》2011,35(18):1918-1948

In an effort to study the relation of fabrics to the critical states of granular aggregates, the discrete element method (DEM) is used to investigate the evolution of fabrics of virtual granular materials consisting of 2D elongated particles. Specimens with a great variety of initial fabrics in terms of void ratios, preferred particle orientations, and intensities of fabric anisotropy were fabricated and tested with direct shear and biaxial compression tests. During loading of a typical specimen, deformation naturally localizes within shear bands while the remaining of the sample stops deforming. Thus, studying the evolution of fabric requires performing continuous local fabric measurements inside these bands, a suitable task for the proposed DEM methodology. It is found that a common ultimate/critical state is eventually reached by all specimens regardless of their initial states. The ultimate/critical state is characterized by a critical void ratio e which depends on the mean stress p, while the other critical state fabric variables related to particle orientations are largely independent of p. These findings confirm the uniqueness of the critical state line in the e ? p space, and show that the critical state itself is necessarily anisotropic. Additional findings include the following: (1) shear bands are highly heterogeneous and critical states exist only in a statistical sense; (2) critical states can only be reached at very large local shear deformations, which are not always obtained by biaxial compression tests (both physical and numerical); (3) the fabric evolution processes are very complex and highly dependent on the initial fabrics. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

Optimum design of stone column-improved soft soil using multiobjective optimization technique     

Kousik Deb  Anirban Dhar 《Computers and Geotechnics》2011

A combined simulation–optimization-based methodology is proposed to identify the optimal design parameters for granular bed–stone column-improved soft soil. The methodology combines a finite difference-based simulation model and an evolutionary multiobjective optimization model. A combined simulation–optimization methodology is developed for two different formulations: (a) the minimization of maximum settlement and the minimization of differential settlement subject to stress constraints; (b) the minimization of maximum settlement, the minimization of differential settlement and the maximization of the degree of consolidation subject to stress constraints. The developed methodology is applied to an illustrative system. Different scenarios are evaluated to examine critical field conditions. The solution results show that the modular ratio and the ultimate stress carrying capacity of the stone column are the most important parameters for optimal design. The obtained results also show the potential applicability of the developed methodology.  相似文献