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ACHIEVEMENTS, CHALLENGES AND COUNTERMEASURES OF GEOLOGICAL DISASTER PREVENTION AND CONTROL IN XINJIANG
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摘要: 新疆地质环境复杂多样、生态环境脆弱敏感，在极端天气及重大工程的扰动诱发下，地质灾害呈现频发、多发、高发态势，重大地质灾害风险的形势严峻复杂。新疆地质灾害以崩滑流为主，根据易发性划分为高、中、低3个等级。本文从地质灾害调查评价、监测预警、综合防治、应急响应、社会参与、学术研究等方面系统地总结了近年来新疆在地质灾害早期识别、预警防控、临灾避险等方面取得的显著成效。针对目前新疆地质灾害防控中存在的隐患早期识别能力不足、预警基础薄弱、理论创新不足、治理体系不够健全等问题，提出构建新疆地区地质灾害防控新机制的设想；基于重大工程扰动对新疆地质灾害进行了重点防治分区；提出构建以制度组织体系、源头管控体系、综合治理体系、科技创新体系为主要内容的新疆地质灾害防控体系，为积极防范和科学应对新疆地质灾害提供了新思路。Abstract: Xinjiang has a complex and varied geological environment and a fragile and sensitive ecological environment. Under the disturbance of extreme weather and major projects, geological disasters have become frequent and high-incidence. The situation of major geological disaster risks is severe and complex. The main types of geological disasters in Xinjiang are collapse, landslide and debris flow. According to the overall division of susceptibility, it is divided into three prone regions, including high, medium and low. This article systematically summarizes the recent main achievements in Xinjiang in early identification of geological disasters, early warning and prevention, emergency avoidance and etc. from the aspects of geological disaster investigation and evaluation, monitoring and early warning, comprehensive prevention and control, emergency response, social participation, as well as academic research. The problems existing in the prevention and control of geological disasters in Xinjiang include insufficient early identification ability of hidden dangers, weak early warning foundation, insufficient theoretical innovation, and incomplete governance system. This paper aims to address these problems and propose a innovative mechanism for preventing and controlling geological disasters in Xinjiang. The key areas of geological disasters prevention and control in Xinjiang are divided based on the disturbance of major projects. A system including institution organization, source control, comprehensive management and scientific and technological innovation, respectively, should be established to improve the geo-disasters' prevention and control in Xinjiang, which provides a new idea for actively preventing and scientifically responding to geological disasters in Xinjiang.
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Key words:
- Geological disaster /
- Prevention and control /
- Challenge /
- Collapse /
- Landslide /
- Debris flow /
- Xinjiang
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图 2 新疆2001~2020年地质灾害发生起数与防治资金投入
Figure 2. The number and the investment in prevention and control of geological disasters from 2001 to 2020 in Xinjiang
图 3 新疆地质灾害防治重点区的划分
Figure 3. Division of key prevention and control areas for geological hazards prevention and control in Xinjiang
图 4 新疆地质灾害防治新机制框图
Figure 4. Block diagram of the new mechanism of geological disaster prevention and control in Xinjiang
表 1 新疆地质灾害重点防治区的划分及其基本情况统计表
Table 1. Statistical table of basic situation of key geological disasters prevention and control zoning in Xinjiang
序号 防治区 地形地貌 地质及水文 分布面积/×104 km 重大工程 地质灾害特点 防治对策 Ⅰ 伊犁谷地山区地质灾害重点防治区 伊犁谷地喀什河、特克斯河及巩乃斯河两侧中低山和丘陵区 区内第四系黄土广泛分布，整体上厚度较大，多具弱－中等湿陷性，地形起伏较大，地形坡度20° ~ 50°，该区域降雨充沛，年均降水量200 ~ 800 mm，积雪厚度40 ~ 50 cm。冻融现象明显，春季融雪水与降雨相互交织，补给地下水，浸润土体，是地质灾害发生的高峰期 4.19 那拉提自然旅游景区、喀拉峻自然旅游景区、库尔德宁自治区级旅游度假区、伊宁－阿克苏铁路、伊宁－巴伦台铁路、G218线那拉提－巴伦台公路、G577线特克斯－昭苏公路等重大工程建设区、大型煤炭基地等 以滑坡、泥石流为主，诱发因素w为短时强降雨、冰雪消融，具有复发性、突发性等特点，黄土滑坡浅层变形严重，生态破坏较严重。泥石流沟谷流域广，纵坡大。往往形成滑坡－泥石流灾害链 防治重点为滑坡灾害，防治须综合考虑生态效应、多层滑动控制等。泥石流防治需综合考虑多级消能，并注重生态环境保护 Ⅱ 天山北麓山区地质灾害重点防治区 天山北麓博乐－木垒中低山丘陵区 区内广泛发育侏罗系或三叠系含煤地层，山高坡陡、沟谷发育，年均降水200 ~ 600 mm。春季融雪水与降雨相互交织，补给地下水，浸润覆盖层土体，软化泥岩和砂质泥岩，往往在第四系覆盖层内部和基覆界面发生变形滑动 4.89 大型煤炭基地、天山天池景区、乌鲁木齐南山国家级旅游度假区、G0711线乌鲁木齐－尉犁公路、S327线北山煤窑－将军庙－五彩湾公路等重大工程建设区 以崩塌、滑坡、泥石流、地面塌陷为主。地质灾害诱发因素主要是短时强降雨、冰雪消融，地面塌陷主要是煤矿采空区塌陷 滑坡和地面塌陷造成地表生态破坏，防治手段需综合考虑生态效应。泥石流防治需综合考虑多级消能，并注重生态环境保护。塌陷地的建筑利用可以考虑灌浆充填治理 Ⅲ 西昆仑山地质灾害重点防治区 分布于塔里木盆地西南缘及帕米尔高原 区内发育古生代变质岩、大理岩，中生代泥岩、砂岩等，地形起伏较大，风化剥蚀较严重，松散堆积物较丰富，河流切割强烈，年均降水量200 ~ 400 mm，局地暴雨频发，冻融现象明显，导致岩体裂隙发育 6.37 帕米尔冰川公园自然旅游景区、G314线布伦口－红其拉甫口岸公路、莫莫克水利枢纽 以崩塌、泥石流为主。泥石流诱发因素主要为短时强降雨、春季冰雪消融，具有规模大、突发性强等特点。崩塌主要以岩质崩塌为主，大多属于高位崩塌，隐蔽性强，诱发因素主要为短时强降雨、春季冰雪消融、地震 地质灾害防治须综合考虑监测预警与工程防治相结合 Ⅳ 天山南麓山区地质灾害重点防治区 天山南麓乌恰－库尔勒中低山丘陵区 区内广泛出露石炭系、侏罗系、早第三系等中、新生代地层，基岩裸露，山高坡陡，沟谷发育，残坡积覆盖层发育，地震频发，年均降水量50 ~ 300 mm，局地暴雨频发 12.64 大型煤炭基地、托木尔自然旅游景区、伊宁－阿克苏铁路、独山子－库车高速公路、G218线那拉提－巴伦台公路、G579线库车－拜城－玉尔滚公路、大石峡水利枢纽 以滑坡、崩塌、泥石流和地面塌陷为主。崩塌、滑坡、泥石流诱发因素多以短时强降雨、冻融等引起，具有复发性、突发性等特点。地面塌陷主要分布在煤矿采空区 地表生态破坏明显，防治需综合考虑生态效应和监测手段 Ⅴ 阿尔泰山区地质灾害重点防治区 分布于阿尔泰山南麓哈巴河－北塔山中低山丘陵区 区内主要发育奥陶、志留、泥盆系碎屑岩、变质岩和华力西期、燕山期花岗岩，大部分基岩裸露，岩体破碎，年降水量180 ~ 300 mm，局地性暴雨频发，冻融现象明显，导致岩体裂隙发育 5.35 喀纳斯国家级旅游度假区、富蕴－塔克什肯口岸铁路、S21线阿勒泰－乌鲁木齐高速公路、G217线阿勒泰－布尔津公路、G216线红山嘴口岸－阿勒泰公路等重大工程 以崩塌、泥石流为主。崩塌诱发因素为短时强降雨、冻融、地震。泥石流诱发因素为短时强降雨、春季冰雪消融，泥石流规模大、流通区长，流域水土流失严重 泥石流的治理需综合考虑多级消能与生态防治相结合的技术手段。对岩质崩塌和松散堆积物崩塌需采取拦挡、镶嵌、捆绑、支护等多种组合的崩塌防治技术 Ⅵ 吐哈盆地山区地质灾害重点防治区 分布于吐鲁番－哈密盆地天山中高山至低山丘陵区 区内主要发育第三系含盐地层，山体基岩裸露，由于构造作用，地形切割强烈，松散堆积物广泛分布，该区气候干燥炎热，植被稀少，年均降水量小于50 mm，局地性暴雨频发 2.96 大型煤炭基地、将军庙－淖毛湖铁路、巴里坤－木垒高速公路、G575线巴里坤－哈密公路等重大工程 以崩塌、泥石流为主。崩塌以岩质崩塌为主，诱发因素为短时强降雨、冻融、地震。泥石流诱发因素为短时强降雨，流域水土流失严重 防治重点为崩塌，可采取拦挡、镶嵌、捆绑、支护等多种组合的防治技术。泥石流防治需考虑多级拦挡与消能技术手段 Ⅶ 准噶尔西部山区地质灾害重点防治区 分布于准噶尔盆地西部低山丘陵区 区内以泥盆系、石炭系分布最为广范，岩性以凝灰岩、层状灰岩、钙质砂岩等为主，冲沟发育，基岩裸露，侵蚀强烈，松散堆积物较发育，年均降水量150 ~ 300 mm。冻融现象明显，导致岩体裂隙发育 4.22 温泉县国家级旅游度假区、G3018线精河－阿拉山口高速公路、G335线塔岔口－托里－巴克图口岸公路等重大工程 以崩塌、泥石流、地面塌陷为主。崩塌、泥石流诱发因素主要为短时强降雨、春季冰雪消融，具有复发性、突发性等特点。地面塌陷主要在采空区范围，造成地表生态破坏较严重 地质灾害造成地表生态破坏，防治手段需综合考虑生态效应 Ⅷ 东昆仑山地质灾害重点防治区 分布于东昆仑山－阿尔金山北麓叶城－若羌中高山、低山丘陵区 区内主要以白云质大理岩、片麻岩、石英岩、麻粒岩为主，第四系主要分布在山间洼地和河流谷地中，构造活动强烈，岩体破碎，沟谷较发育，松散堆积物丰富，年均降水量50 ~ 200 mm，局地暴雨频发。冻融现象明显，导致岩体裂隙发育 14.19 若羌－青海花土沟750 kV联网工程、依吞布拉克－若羌公路、玉龙喀什水利枢纽、策勒河昆仑水利枢纽等重大工程 以崩塌、泥石流为主。地质灾害诱发因素以短时强降雨、冻融、地震为主，崩塌主要以岩质崩塌为主，大多属于高位崩塌 泥石流流域水土流失严重，需考虑多级拦挡与生态保护技术手段。崩塌多为高位，隐蔽性强，其防治应综合考虑监测预警与工程防治相结合 
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