基于WWW构建3DGIS的若干关键技术探讨

本文分析了在目前的技术条件下GIS发展的主导趋势，提出一个在WWW上实现3DGIS的可行性方案。通过对其中的几项关键支撑技术进行详细介绍，阐述系统的工作原理，并对该方案进行评价。     

Simulation-based risk assessment of contaminated sites under remediation scenarios, planning periods, and land-use patterns—a Canadian case study

Risk assessment of contaminated sites is crucial for quantifying adverse impacts on human health and the environment. It also provides effective decision support for remediation and management of such sites. This study presents an integrated approach for environmental and health risk assessment of subsurface contamination through the incorporation of a multiphase multicomponent modeling system within a general risk assessment framework. The method is applied to a petroleum-contaminated site in western Canada. Three remediation scenarios with different efficiencies (0, 60, and 90%) and planning periods (10, 20, 40, 60, and 80 years later) are examined for each of the five potential land-use plans of the study site. Then three risky zones with different temporal and spatial distributions are identified based on the local environmental guidelines and the excess lifetime cancer risk criteria. The obtained results are useful for assessing potential human health effects when the groundwater is used for drinking water supply. They are also critical for evaluating environmental impacts when the groundwater is used for irrigation, stockbreeding, fish culture, or when the site remains the status quo. Moreover, the results indicate that the proposed method can effectively identify risky zones with different risk levels under various remediation actions, planning periods, and land-use patterns.     

南京市滑坡形成机理及诱发条件研究

南京市滑坡地质灾害屡有发生，通过对已发生的土质、岩质滑坡形成机理的研究，从中找出影响滑坡发生、发展的自然因素和人为因素，分析了滑坡的诱发条件。     

Hydrogeological and geotechnical assessments of the Kadifekale landslide area, İzmir, Turkey

 The study area is located in the south of İzmir city centre in an area built without planning permission or any overall city plan. In this area, a number of mass movements occurred in the past and the region is still an active landslide field at present. The real sliding factor is geological structure, which is made up of hard volcanic rocks overlying soft Neogene clayey soils, and forms a typical structure prone to sliding. Unplanned human activities change the hydrogeological and geotechnical stabilities of the geological formations in a negative way. Rain and water leaking either directly from the mains or septic holes infiltrate into the ground and act as one of the factors in causing landslides. It is clearly shown that the irregular urbanization in and around Kadifekale is one of the factors contributing to the landslides in the area. To prevent the occurrence of landslides in the study area an effective surface and under ground drainage should be established. Rain and wastewater should be removed from the area by separate systems. Slopes should be reduced, water-loving trees should be planted and construction of high rise buildings should be avoided. Received: 12 December 1997 · Accepted: 4 April 2000     

Cause-Effect Models of Large Landslides

Within the scope of the International Decade ofNatural Disaster Reduction (IDNDR), cause-effectmodels of large landslides are being developed toestimate hazard. This work is based on a structuralexploration of the landslide areas mainly by seismicmethods. Information about the status of deformationis obtained by comparison of the actual topographywith a reconstruction of the original topography, byGPS, and by SAR interferometry. Geologic andgeomorphological evidence, as well as relevantinformation from other geo-scientific disciplines, isconsidered. The Finite Element Method is used to modelthe initial phase of a mass movement. Later on thismodeling will be extended to the quasi-stationarycreep phase and the transition from creeping to rapidsliding.Four large landslides within the crystalline rocks ofthe Eastern Alps have been investigated since 1997.Two of them are evaluated so far, and are presented inthis paper. The largest one is the Köfelslandslide with a total volume of 3.9 km³ and apotential energy release of 5 × 10¹⁶ Joule.Refraction and reflection multi-component seismictechniques were used to resolve structure and elasticparameters of the landslide masses. For the modelingof the initial phase of the landslides by the FiniteElement Method a strain softening behavior of the rockmass has been assumed. The development of softened orfractured zones was successfully simulated, inagreement with the structures obtained by the seismicmeasurements.     

世界滑坡目录工作组建议的滑坡术语

本文介绍了联合国教科文组织世界滑坡目录工作组建议的描述滑坡特征，量度、活动状态，活动型式和类型等的基本滑坡术语。     

中国滑坡堵江事件目录

本文介绍了与滑坡堵江事件有关的几个基本概念，列出了１４７个滑坡堵江事件的“中国滑坡堵江事件目录”，目录中包括滑坡名称，发生时间，体积，所堵江河，堵江历时，诱发因素和主要危害等。     

宝天铁路滑坡的遥感调查与规律探讨

本文介绍了利用遥感技术对宝天铁路滑坡和崩塌灾害的调查与动态分析。通过对5个时相不同比例尺的航空像片的分析判读,在宝天段线路两侧各1公里的地带内共发现滑坡398处、崩塌206处,其中涉及线路的滑坡61处、崩塌94处。其次,在综合分析地形、地质、水文和人文等病害因素的基础上,探讨了该区域工程病害的发生规律。分析结果表明,滑坡以发生在黄土者最多,其次为破碎的变质岩和风化的花岗岩,而砂砾岩中最少;崩塌以发生在花岗岩者居多,其次是变质岩系,再次为黄土,砂砾岩中最少。该成果不仅发现了比既有资料多得多的滑坡数量,而且初步摸到了滑坡的发生规律,从而为该段线路病害的防治提供了可靠的依据。     

Structure and Dynamics of Katabatic Flow Jumps: Idealised Simulations

For the first time, results from a high-resolution numerical simulation (with horizontal grid spacing of 35m) were used to reveal the detailed structure near an atmospheric katabatic jump over an idealized slope. The simulation represents flow over the slopes of Coats Land, Antarctica for austral winter conditions. The katabatic jump is characterised by an updraft with vertical velocities of order 1ms⁻¹ and serves as a possible forcing mechanism for the gravity waves frequently observed over the ice shelves around the Antarctic. Results also indicate that strong turbulence is generally confined within a mixing zone near the top of the katabatic layer upstream of the jump and extends downstream through the top of the strong updraft associated with the jump. Detailed analyses of momentum and heat budgets across the katabatic jump indicate that, upstream of the jump, turbulent mixing is important in decelerating the upper part of the katabatic layer, while within the jump the upslope pressure gradient force associated with the pool of cold air plays a role in decelerating the flow near the surface. The heat budget near the jump reveals a simple two-term balance: the turbulent heat flux divergence is balanced by the advection. A comparison of model results with available theories indicates that mixing between layers of different potential temperature structure indeed plays some role in the development of katabatic flow jumps, especially for strong jumps. Theories used to study katabatic jumps should include this mixing process, of which the amount depends on the intensity of the jump. A conceptual model of a katabatic jump, including the main dynamical processes, is constructed from these detailed analyses.     

Hydraulic and numerical study on the generation of a subaqueous landslide-induced tsunami along the coast

By carrying out the hydraulic experiments in a one-dimensional open channel and two-dimensional basin, we clarified the process of how a landslide on a uniform slope causes the generation of a tsunami. The effect of the interactive force that occurs between the debris flow layer and the tsunami is significant in the generation of a tsunami. The continuous flow of the debris into the water makes the wave period of the tsunami short. The present experiments apply numerical simulation using the two-layer model with shear stress models on the bottom and interface, and the results are compared. The simulated debris flow shows good agreement with the measured results and ensures the rushing process into the water. We propose that the model use a Manning coefficient of 0.01 for the smooth slope and 0.015 for the rough slope, and a horizontal viscosity of 0.01 m²/s for the landslide; an interactive force of 0.2 for each layer is recommended. The dispersion effect should be included in the numerical model for the propagation from the shore.