滑坡基本概念类型特征及影响因素(47页).pptVIP

滑坡基本概念、类型、特征及影响因素 一、滑坡术语 相关术语 landslide dam - an earthen dam created when a landslide completely blocks a stream or river. landslide hazard map - hazard maps show the areal extent of threatening processes: where landslide processes have occurred in the past, where they occur now, and the likelihood in various areas that a landslide will occur in the future. CO Survey, 1988 相关术语 landslide inventory maps - inventories identify areas that appear to have failed by landslide processes, including debris flows and cut-and-fill failures. CO Survey, 1988 landslide susceptibility map - these maps go beyond an inventory map and depict areas that have the potential for landsliding. These areas are determined by correlating some of the principal factors that contribute to landsliding, such as steep slopes, weak geologic units that lose strength when saturated, and poorly drained rock or soil, with the past distribution of landslides. CO Survey, 1988. 相关术语 mitigation - activities that reduce or eliminate the probability of occurrence of a disaster and/or activities that dissipate or lessen the effects of emergencies or disasters when they actually occur. CO Survey, 1988. mudflow - a general term for a mass-movement landform and process characterized by a flowing mass of fine-grained earth material with a high degree of fluidity. The water content may range up to 60%; also spelled mudflow. AGI 相关术语 perched ground water - unconfined ground water separated from the underlying main body of ground water by unsaturated rock. AGI pore water pressure - a measure of the pressure produced by the head of water in a saturated soil and transferred to the base of the soil through the pore water. This is quantifiable in the field by the measurement of free water surface level in the soil. Pore water pressure is a key factor in failure of a steep slope soil, and operates primarily by reducing the weight component of soil shear strength. Chatwin and others, 1994. pore water, or interstitial wate