Mapping of micro topography using airborne laser scanning

Intense rainfall conditions and seismic activity commonly trigger fluidised landslides which are characterized by rapid movement and long run-out. They are potentially a very dangerous form of landslide phenomena and may result in extensive damage due to their sudden movement. Until now, photogrammetry has been used to produce maps and investigate such landslides in areas where these disasters occur. Recently, however, airborne laser scanning technology has become a promising technique for making topographical maps and investigating the micro topographic details of these landslide disasters, particularly on slopes around urban areas where the potential risk is high. In this study, airborne laser scanning was carried out in the Tama Hills, near Tokyo, Japan, which is extensively affected by this type of landsliding. The effectiveness of this technique was tested and compared with a laser contour map and aerial photograph interpretations.     

Archaeological investigation by electrical resistivity tomography: a preliminary study

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This paper describes a method in which vertical resistivity sections are generated tomographically from measurements on a linear array of equally spaced electrodes inserted at the ground surface. The array is multiplexed to a resistivity meter which gathers one set of all possible independent apparent resistivity measurements and the geophysical section is then reconstructed by backprojecting these weighted data, along equipotentials, into the subsurface. The technique has been evaluated numerically and in field trials over shallow archaeological structures at Fountains Abbey.     

航空遥感数据的贝叶斯网络分类

介绍了利用贝叶斯网络对航空遥感数据进行分类的算法和过程，认为贝叶斯网络具有以下优点： 充分利用和综合了先验知识 与样本信息； 采用有向无环图（DAG）的方式描述了多特征数据间的相互关系； 给出了联合概率表，并通过联合概率表给出了每个 像元属于不同类别的概率。研究结果表明，贝叶斯网络可以为遥感数据分类提供一种新方法。     

Airborne electromagnetics supporting salinity and natural resource management decisions at the field scale in Australia

Airborne geophysics has been used at the catchment scale to map salt stores, conduits and soil variability, but few studies have evaluated its usefulness as a land management tool at the field scale. We respond to questions posed by land managers with: (1) comparison of airborne and ground-based electromagnetic surveys in the Lower Balonne catchment, Queensland, and (2) comparison with historical and anecdotal knowledge of landscape response in the country around Jamestown in mid-South Australia.In the Lower Balonne, direct comparison between ground electromagnetic survey (EM) and airborne electromagnetics (AEM) showed a strong relationship for both the absolute values and spatial patterns of conductivity. The penetration of AEM to greater than 100 m is valuable in defining hydrological barriers. In the Jamestown area, AEM conductivity corresponded well with specific outbreaks of salinity and observed variability in crop response; local inconsistencies at the ground surface could be resolved when sub-surface data were considered. AEM can provide valuable information at the field scale that is relevant to salinity management. Farmers can have confidence in any of these techniques (historical information, EM and AEM) and they may directly compare or integrate the results.     

Thermal characteristics of coal fires 2: Results of measurements on simulated coal fires

In this paper we present thermal characteristics of coal fires as measured during simulated fires under an experimental setting in Germany in July 2002. It is thus a continuation of the previously published paper “Thermal surface characteristics of coal fire 1: Results of in-situ measurement”, in which we presented temperature measurements of real subsurface coal fires in China [Zhang, J., Kuenzer, C., accepted for publication. Thermal Surface Characteristics of Coal Fires 1: Results of in-situ measurements. Accepted for publication at Journal of Applied Geophysics.]. The focus is on simulated coal fires, which are less complex in nature than fires under natural conditions. In the present study we simulated all the influences usually occurring under natural conditions in a controllable manner (uniform background material of known thermal properties, known ventilation pathways, homogeneous coal substrate), creating two artificial outdoor coal fires under simplified settings. One surface coal fire and one subsurface coal fire were observed over the course of 2 days. The set up of the fires allowed for measurements not always feasible under “real” in-situ conditions: thus compared to the in-situ investigations presented in paper one we could retrieve numerous temperature measurements inside of the fires. Single temperature measurements, diurnal profiles and airborne thermal surveying present the typical temperature patterns of a small surface-and a subsurface fire under undisturbed conditions (easily accessible terrain, 24 hour measurements period, homogeneous materials). We found that the outside air temperature does not influence the fire's surface temperature (up to 900 °C), while fire centre temperatures of up to 1200 °C strongly correlate with surface temperatures of the fire. The fires could heat their surrounding up to a distance of 4.5 m. However, thermal anomalies on the background surface only persist as long as the fire is burning and disappear very fast if the heat source is removed. Furthermore, heat outside of the fires is transported mainly by convection and not by radiation. In spatial thermal line scanner data the diurnal thermal patterns of the coal fire are clearly represented. Our experiments during that data collection also visualize the thermal anomaly differences between covered (underground) and uncovered (surface) coal fires. The latter could not be observed in-situ in a real coal fire area. Sub-surface coal fires express a much weaker signal than open surface fires and contrast only by few degrees against the background. In airborne thermal imaging scanner data the fires are also well represented. Here we could show that the mid-infrared domain (3.8 μm) is more suitable to pick up very hot anomalies, compared to the common thermal (8.8 μm) domain. Our results help to understand coal fires and their thermal patterns as well as the limitations occurring during their analysis. We believe that the results presented here can practicably help for the planning of coal fire thermal mapping campaigns — including remote sensing methods and the thermal data can be included into numerical coal fire modelling as initial or boundary conditions.     

对地观测与地理信息系统

20世纪地球科学进步的一个突出标志是人类开始脱离地球从太空观测地球（Earth Observation from Space）,并将得到的数据和信息在计算机网络以地理信息系统形式存储、管理、分发、流通和应用。比较全面地介绍了上述过程的若干关键技术：航空航天遥感技术、GPS技术和地理信息系统技术的最新发展及其未来计划。重点介绍了气象卫星、资源卫星、制图卫星、EOS计划以及我国航空航天遥感的主要成就;GPS全球定位系统及在我国的应用、卫星测高技术、我国的甚长基线干涉测量与卫星激光测距;GIS的发展历史及其特点、我国GIS的发展概况与现状等,最后提出“Geo-Information for all”的观点。     

Matlab软件包在地球物理数值计算与辅助教学中的应用

针对地球物理数值计算和教学过程中的难点和重点,借助Matlab软件包,给出了具体的应用实例.首先,采用Matlab软件包实现了重力勘探、磁法勘探和电法勘探等地球物理勘探方法中的数值计算;其次,利用Matlab软件包,给出了直观形象的图形界面,丰富了教学内容,取得了良好的教学效果,为课程教学方法和手段的改革探索了新的思路.     

西藏扎西康铅锌多金属矿床控矿构造的电性特征及找矿预测

西藏扎西康铅锌多金属矿床位于喜马拉雅碰撞造山带东段的多金属成矿带内。为探明该矿床控矿构造的电性特征,笔者在矿区布设两条地球物理（音频大地电磁AMT、大地电磁MT）测线进行数据采集,并经过详细的数据处理和反演计算,得到较好的地下电性结构剖面。结合长期野外调查和物性、钻孔资料,解译出9条断裂,其中包含4条含矿断裂和4条隐伏断裂,1个深部隐伏岩体,划定2个深部有利找矿点（即F_t2和F₂₄断裂深部）。     

综合电法在云南东北某铅锌矿区隐伏矿找矿中的应用效果

通过在云南东北某铅锌矿区开展地面直流充电、激电中梯和瞬变电磁综合物探,对Ⅰ号主矿体在南西向的延伸边界做出了推测,并对其做了定量解释计算;同时根据综合异常推测在Ⅰ号主矿体东南侧还存在多条平行矿体.物探成果为本矿区的隐伏矿找矿提供了重要依据,并很好地指导了后来的探采工程布设,取得了满意的找矿效果.     

皖中沙湖山金多金属矿床特征及找矿潜力分析

根据斑岩型铜矿成矿系列理论,沙溪斑岩型铜金矿床外围可能存在浅成中低温热液金银铅锌矿。近年在沙湖山地区已发现小型破碎蚀变岩型脉状金铅锌多金属矿床。通过对沙湖山地区成矿地质背景、矿区及矿床地质、地球物理和地球化学特征综合研究、分析,认为沙湖山地区具有较好的寻找浅成中低温热液金银铅锌矿的潜力。