西双版纳勐海勐满热泉型金矿

勐满金矿赋存在澜沧群浅变质岩系和侏罗系红层中,金富集对围岩岩性无明显选择,具低温热液蚀变特征,属热泉、变质热液成因。     

近现代时期若干北京古旧地图研究与数字化处理

本文介绍了若干幅 1 90 7年至 1 948年间由陆地测量总局等不同权威机构测绘、编制的古旧北京地图 ,为开展近现代时期北京城市地理、土地覆盖变迁研究、为古地图研究与利用提供参考。对古旧地图的应用及数字化技术处理进行了探讨。     

福建晋江海岸带老红砂多期发育模式初步研究

我国东南沿海广泛分布的老红砂是海岸环境演变的产物。通过对福建晋江海岸带科任(KR)老红砂剖面加密采样进行OSL测年和粒度分析,初步确定了老红砂发育期次及其形成时代。以OSL测年值为基础,在统一的时间标尺上综合对比全球海平面和东亚季风变化序列,探讨了老红砂发育模式及其环境意义。研究表明: 科任老红砂主要是晚更新世末次间冰期以来发育的,主要发生在约125~9ka期间,可以划分为6个沉积期,分别为125~115ka,105~97ka,84~74ka,61.5~52.0ka,39~29ka和15~9ka,期间可能存在至少5次明显的沉积间断。结合台湾海峡的水深变化特点分析,当海平面低于-70m时,由于研究区远离古海岸线,因而不可能有海岸风沙沉积; 当海平面低于-15m高于-70m时,受到较强冬季风吹扬搬运海滩砂再沉积过程的影响,研究区可能有海岸风沙发育; 当海平面高于-15m时,古今海岸线位置接近,在各种强度的冬季风作用下,研究区都会有海岸风沙广泛发育,并经历强烈的红化作用。即,科任老红砂主要发育于晚更新世末次间冰期以来气候暖湿的高海面和较高海面时期,而在末次冰期的低海面时期多次缺失海岸风沙沉积,尤其是末次盛冰期(LGM)的最低海面时期,现代海岸带所在区域老红砂发生沉积间断。     

老年人脑转移瘤的CT诊断及临床特点

目的：通过临床及手术病理对照，分析了63例老年人脑转移瘤的CT表现，探讨老年人脑转移瘤的CT征象及诊断意义。材料与方法：63例患者包括多发者39例，单发者24例。CT检查病例全部平扫，其中49例行增强扫描，观察CT对脑转移瘤的定位及定量价值，总结CT变化规律。结果：CT发现病灶118个，其中单发病灶34个占28.3%，2个病灶的58个占49%，2个病灶以上的26个占22.7%。目前CT对老年人脑转移瘤的定位，定量，定性都有特征性，方便快捷应为首选。     

基于TSL模型构建的活态遗产地连续性空间生产研究——以丽江古城为例

活态遗产地演变发展是连续性空间生产过程,揭示其特征与逻辑对于活态遗产地的保护、利用与传承具有重要意义。将表达遗产地活态性的3个要素——传统、地点、生活与“空间三元辩证法”相耦合构建TSL（Tradition-Site-Living）模型,并以丽江古城为例,探讨活态遗产地持续变化的一般规律。结果发现：1）古城经历了三个阶段的空间生产,即政治功能主导下的“空间中的消费”,工商功能主导下的“空间中的生产”,旅游功能主导下的“空间的生产和消费”;2）外部环境因素变化促使古城核心使用功能演替,引发生活、地点、传统相互作用,从而实现各个阶段的空间生产过程;3）活态遗产地连续性空间生产是外部因素驱动内生机制运行的结果,遵循时空延续变化、外部环境因素驱动、内部活态要素运作三大逻辑。活态遗产地是由时间、环境、空间叠合而成的时空连续体,TSL模型为揭示活态遗产地持续变化的基本规律提供了理论框架。     

基于高空间分辨率遥感影像的广东省“三旧”造项目进度监测技术研究与应用

为推进广东省“三旧”改造建设,促进节约集约用地,本文提出一种基于高空间分辨率遥感影像的“三旧”改造进度监测技术,该技术在多特征空间基础上,将最大似然与点对点(P2P)分类算法基于类别概率进行加权融合,解决了高空间分辨率遥感影像因地物信息过于丰富、光谱分辨率受限、光谱可变性等特性,导致变化检测精度受影响等问题,现已应用于“三旧”改造进度监测系统中,实现了“三旧”改造项目的查询、分析、统计与展示功能.     

Sedimentological study of the Chernobyl NPP site to schematise radionuclide migration conditions

The approach, methods and results of a sedimentological study of a near-surface stratum of Late Pleistocene-Holocene deposits in the near-zone (5–10 km radius) of the Chernobyl Nuclear Power Plant are presented. Sedimentological analyses are carried out at three levels of detail: regional-, local- and object-scale. The unsaturated zone and unconfined aquifer at the site are composed of two main genetic types of deposits, aeolian and alluvial, including several dynamic facies. Consideration of lithological properties leads to following ranking of the main genetic sediments facies with respect to radionuclide migration retardation potential: aeolian <alluvial channel <alluvial overbank <alluvial abandoned channel. Based on sedimentological interpretations, the geological environment is schematised into a set of typical geological sections possessing different radionuclide retardation potential.     

Coupling water flow and solute transport into a physically-based surface-subsurface hydrological model

A distributed-parameter physically-based solute transport model using a novel approach to describe surface-subsurface interactions is coupled to an existing flow model. In the integrated model the same surface routing and mass transport equations are used for both hillslope and channel processes, but with different parametrizations for these two cases. For the subsurface an advanced time-splitting procedure is used to solve the advection-dispersion equation for transport and a standard finite element scheme is used to solve Richards equation for flow. The surface-subsurface interactions are resolved using a mass balance-based surface boundary condition switching algorithm that partitions water and solute into actual fluxes across the land surface and changes in water and mass storage. The time stepping strategy allows the different time scales that characterize surface and subsurface water and solute dynamics to be efficiently and accurately captured. The model features and performance are demonstrated in a series of numerical experiments of hillslope drainage and runoff generation.     

The ‘old red sandstone’ of county mayo,Northwest Ireland

The distribution and stratigraphic relations of the Old Red Sandstone of the Clew Bay area. County Mayo are described. They comprise two groups both dominated by conglomerates, one Lower Devonian and one Middle Devonian, which have differing clast contents and which are separated by faults. The sediments are described in terms of five facies which are all interpreted as alluvial fan deposits. Provenance data from palaeocurrents and clast composition suggest transport predominantly to the west-northwest but one formation shows an opposite sense of transport. The rocks are folded about northeast-southwest axial traces and are affected by numerous faults. Structures are more complex than those of the Lower Carboniferous rocks which unconformably overlie the Devonian. A similar tectonosedimentary setting to the Old Red Sandstone of parts of the Scottish Caledonides is indicated.     

海南文昌涣文村老红砂剖面的磁化率测量及意义

通过对海南文昌县涣文村老红砂剖面的野外调查和磁化率测量, 绘制了该剖面磁化率曲线; 分析了剖面磁化率特征与剖面颜色及红化过程的关系。指出剖面磁化率可以作为反映老红砂堆积过程中(及以后)气候变化的物理参数。开展老红砂堆积连续剖面的磁化率测量, 以此进行气候地层的划分与对比, 对华南沿海乃至更大范围环境变化的研究具有重要意义