西藏甲玛斑岩矿床系统地质、蚀变、矿化的三维地质模型

甲玛矿床位于西藏冈底斯成矿带东段,是公益性与商业性勘查结合取得的重要成果。目前已累计探明和控制铜资源量超过700万吨,共伴生钼、铅锌、金、银资源量均达到大型以上规模。本文在充分收集、整理甲玛矿床最新勘查资料、研究成果的基础上,运用MICROMINE软件三维建模及可视化技术,遵循点→线→面→体的构建原则,进行人机交互分析,构建了甲玛矿床地质、蚀变、矿体三维实体模型,并根据不同矿体品位分布变化的实际情况,对矿体模块模型进行克里格法或距离反比加权法品位插值,构建各种元素的矿化模型。并综合国内外对斑岩、矽卡岩矿床的研究新趋向对模型进行了地质解译,认为甲玛斑岩矿床是由斑岩钼铜矿体、矽卡岩铜多金属矿体、角岩铜钼矿体以及破碎带中独立金矿体构成的"四位一体"典型斑岩成矿系统产物,其中矽卡岩主要有接触带近端矽卡岩、层间构造中的远端矽卡岩以及受控于推滑覆构造产出的矽卡岩三种产出型式,由岩浆热液沿层间构造和推滑覆构造扩散交代大理岩和角岩形成;研究认为甲玛斑岩矿床具有典型的斑岩矿床蚀变系统,但蚀变分带有所差异,钾化带与青磐岩化带是在相对碱性条件下形成,而绢英岩化带与泥化带趋向于在相对酸性条件下形成。此外,大规模的角岩、矽卡岩对寻找深部斑岩矿体具有指示意义,甲玛斑岩矿体、角岩矿体仍具巨大的找矿潜力。因此,本研究构建的甲玛三维模型直观地展示了矿区地层、岩体、构造分布情况、赋矿层位、矿化品位分布规律以及蚀变分带特征,为甲玛矿床的成因、成矿规律总结、找矿勘查、矿山生成开发等综合研究提供重要的科学依据。     

浙江江山地区地质影像特征

以1976年的航空相片为主要工作图像及1997年的陆地卫星TM图像为参考图像，研究了浙江江山地区岩石地层、地质构造的影像特征。对厘定的17个岩石地层单位，以上横塘、伍家弄、藕塘底三个典型地层剖面位置为样区，分析和总结了各地层单位的影像特征。实践证明，运用60、70年代的航空相片和90年代的陆地卫生TM图像资料，对当前江山地区植被覆盖度高、土壤发育或地形地貌复杂，地质工作者难以涉足的地区进行l：5万区域地质填图，特别是填制“组图”具有明显的应用效果。通过对各种地质体影像特征的认真分析和总结，并结合野外实地检查验证，可在遥感图像上划分地层单元。勾绘地层界线和解译地质构造。这对加快我国l：5万区域地质填图工作步伐，提高填图质量具有重要的实际意义。     

地下矿地测图形处理系统的研制和应用

地下矿地测图形处理系统是“地下矿地测信息管理系统”的核心部分。它以图形数据自动化处理、机助成图和动态修改为目标,利用人工智能技术自动推断矿岩界线,生成和更新矿山地测中的几种主要图件,为日常地测管理和矿量计算提供完整的技术资料。本文较详细地介绍了该系统的总体设计、结构与功能、系统实现的关键技术及其应用情况。     

Irrigation effects on the salinity of the Arba and Riguel Rivers (Spain): present diagnosis and expected evolution using geochemical models

This work diagnoses the present salinity of the Riguel and Arba Rivers (Spain) and predicts its expected evolution using geochemical models applied to the modernization of the actual Bardenas I and the completion of irrigation in the Bardenas II irrigation districts. The results show a progressive increase in salinity (from 0.39 to 2.21 dS/m electrical conductivity) in the Riguel-Arba system, due to the cumulative collection of irrigation return flows and its progression towards more saline facies. The Bardenas I modernization, involving an increase in irrigation efficiency from 50 to 90%, will decrease the volume and salinity of the Riguel River by 30%. In contrast, irrigation of the new 24,000 ha Bardenas II land will increase the flow (12%) and salinity (21%) of the Arba River. Geochemical models may help in providing sensible estimates on the impact of irrigation on the salinity of the receiving water bodies.     

Confined channel-levee complex development in an elongate depo-center: Deep-water Tertiary strata of the Austrian Molasse basin

A basin axial-channel belt was largely responsible for the observed distribution of coarse-grained gravity-flow deposits in the Tertiary Puchkirchen and basal Hall formations of the Molasse foreland basin in Upper Austria. Elements of this depositional system, mapped in three-dimensional (3D) seismic-reflection data, include channel-belt thalweg, mass-transport complexes, overbank wedge, overbank lobe, and tributary channel. The primary objective of this paper is to develop a comprehensive understanding of the sedimentary processes that were prevalent in the channel-belt complex through the analysis of well data, including drill cores and wireline logs, in conjunction with 3D seismic interpretations.     

成都地铁1号线工程建设面临的地质问题及对策

成都地铁1号线车站和区间隧道主体结构均位于砂卵石地层中。建设中会遇到诸多施工地质与环境地质问题。例如大粒径、高强度砾石和透镜体砂层对盾构机选型、盾构施工及降水施工产生较大影响。同时,地铁工程建设可能会对周边建筑物和地下水径流产生一定影响。但在充分总结类似工程修建的技术和经验基础上。通过选用合理的施工方法、施工设备、施工工艺、施工组织以及采取合理的工程措施,是能够得到解决或控制的。     

Evaluating the meaning of “layer” in the martian north polar layered deposits and the impact on the climate connection

Using data from the High Resolution Imaging Science Experiment (HiRISE) aboard the Mars Reconnaissance Orbiter, we reassess the methods by which layers within the north polar layered deposits (NPLD) can be delineated and their thicknesses measured. Apparent brightness and morphology alone are insufficient for this task; high resolution topographic data are necessary. From these analyses, we find that the visible appearance of layers depends to a large degree on the distribution of younger, mantling deposits (which in turn is partially influenced by inherent layer properties) and on the shape and location of the particular outcrop. This younger mantle partially obscures layer morphology and brightness and is likely a cause of the gradational contacts between individual layers at this scale. High resolution images reveal that there are several layers similar in appearance to the well-known marker bed discovered by Malin, M., Edgett, K., 2001. J. Geophys. Res. 106, 23429-23570. The morphology, thicknesses , and separation distances of these marker beds, as gleaned from a high resolution stereo digital elevation model, lend insight into the connection between stratigraphy and climate.     

The ore genesis of the Jebel Mecella and Sidi Taya FBa (ZnPb) Mississippi Valley-type deposits,Fluorite Zaghouan Province,NE Tunisia,in relation to Alpine orogeny: Constraints from geological,sulfur, and lead isotope studies

Jebel Mecella and Sidi Taya F–(BaPbZn) deposits are located within the Fluorite Zaghouan Province (NE Tunisia). The mineralization occurs along the unconformity surface between the Jurassic limestones and Upper Cretaceous rocks. The mineralization consists mainly of fluorite, barite, sphalerite, and galena. The δ³⁴S values of barite at Jebel Mecella (14.8–15.4‰) and at Sidi Taya (21.6–22.2‰) closely match those of the Triassic evaporites and Messinian seawater, respectively. The range of δ³⁴S values of galena and sphalerite in both deposits (?6.9 to +2.4‰) suggests the involvement of thermochemical sulfate reduction and possibly organically-bound sulfur in the generation of sulfur. Lead isotope data with ²⁰⁶Pb/²⁰⁴Pb, ²⁰⁷Pb/²⁰⁴Pb, and ²⁰⁸Pb/²⁰⁴Pb ratios of 18.893–18.903, 15.684–15.699, and 38.850–38.880, respectively suggests a single homogeneous source reservoir of Paleozoic age and/or the homogenization of the Paleozoic–Cretaceous multireservoir-derived fluids along their long migration paths to the loci of deposition during the Alpine orogeny.     

新疆阿克陶玛尔坎苏锰成矿带地质特征及成矿条件分析

玛尔坎苏锰成矿带沿玛尔坎苏河上游分布,东西延伸超过40 km。该成矿带以石炭系细碎屑岩-碳酸盐岩沉积建造为主,属典型的海相沉积型锰矿。锰矿带含矿层位稳定,矿体厚度大(最厚30.61 m),品位富(平均品位24%～35%,最高68.5%),矿石矿物以菱锰矿为主,属于低铁中磷类型。综合分析认为玛尔坎苏锰成矿带形成于滨浅海环境,成锰期处于一种安静、还原的水体环境。锰质来源以深源物质为主,与火山活动、热水活动关系密切。     

浅谈原本地质科技档案的整理

随着信息技术突飞猛进的向前发展，人类已经进入了一个数字化、网络化的新时代。针对如何使现有的原本地质科技档案的管理工作适应新形势的要求，提出了对原本地质科技档案重新整编的原则、方法，以及能使原本地质科技档案符合规范化、标准化要求，以达灵活方便、事半功倍之目的。