基于多源遥感数据地下煤火空气渗入/逸散区域研究

Study on air infiltration/escape area of underground coal fires using multi-source remote sensing data

基于地下煤火导致地表的沉降、温度、植被变化在一定程度上可反映火区的动态变化过程。本文采用普适性单通道算法和像元二分法反演火区地表温度与植被盖度,差分干涉“两轨法”提取沉降特征。结合地表沉降,地表高/低温区域和高/低植被盖度区域分布特征,尝试对火区高温烟气逸散区域和低温空气进入区域进行分析。结果表明:2013年高温区域面积占比最大(27.18%),2015年低温区域面积占比最大(16.51%);研究区整体以Ⅰ级植被覆盖区域和Ⅱ级植被覆盖区域为主,Ⅰ级植被覆盖区域2003年面积最大(24.200 km^(2),占比99.48%);沉降高值由9.591 mm波动变化为-3.124 mm,沉降低值由-19.132 mm波动变化至-26.059 mm;2014—2017年温度异常区域和Ⅰ级植被覆盖区域叠加处理有效裂隙区点位置从5617个减少至863个,再增加至3578个,整体减少2039个;低温区域和Ⅳ级植被覆盖区域叠加处理有效裂隙区点位置从4个增加至13个,总体约增加3倍;典型空气进入通道与典型烟气逸散通道沉降最低值均出现在20160131—20160319干涉对,分别为-262.402 mm和-232.832 mm,最高值则出现在20160506—20160530干涉对,分别为602.910 mm和564.202 mm。

Based on the changes of surface subsidence,temperature and vegetation caused by underground coal fires,the dynamic change process of fire area can be reflected to a certain extent.In this paper,the universal single channel algorithm and pixel dichotomy are used to retrieve the surface temperature and vegetation coverage in the fire area,and the differential interference“two track method”is used to extract the settlement characteristics.Combined with the distribution characteristics of surface subsidence,surface high/low temperature area and high/low vegetation coverage area,this paper attempts to analyze the high-temperature smoke escape area and low-temperature air entry area in the fire area.The results show that the high temperature area accounted for the largest proportion(27.18%)in 2013 and the low temperature area accounted for the largest proportion(16.51%)in 2015.The study area is mainly covered by classⅠand classⅡvegetation.The area of classⅠvegetation is the largest in 2003(24.200 km^(2),accounting for 99.48%).The high settlement value fluctuates from 9.591 mm to-3.124 mm,and the low settlement value fluctuates from-19.132 mm to-26.059 mm.From 2014 to 2017,the number of effective fracture points in the superposition treatment of temperature abnormal areas and classⅠvegetation covered areas decreased from 5617 to 863,and then increased to 3578,with an overall decrease of 2039.The number of effective fracture points in the superposition treatment of low-temperature area and gradeⅣvegetation coverage area increased from 4 to 13,an overall increase of about 3 times.The lowest settlement values of typical air inlet channel and typical flue gas escape channel appear in 20160131-20160319 interference pair,which are-262.402 mm and-232.832 mm respectively,while the highest settlement values appear in 20160506-20160530 interference pair,which are 602.910 mm and 564.202 mm respectively.