利用Landsat热红外影像探测地下煤火区范围——以乌达煤田为例

Detecting the Underground Coal Fire by Using Landsat Thermal Infrared Imagery——Taking Wuda Coalfield as an Example

以Landsat系列热红外影像为主要数据源,采用阈值分析技术,提取了乌达煤田2002年、2007年和2013年地下煤火燃烧范围。结果表明,大规模的煤田开采活动导致2007年火区面积比2002年增加将近一倍,但随着2010年大范围灭火工作的展开,到2013年火区灾情得到了有效遏制。与地面实测数据相比较,遥感估算的火区面积误差为5%~10%,但白天太阳辐射导致地表温度反演精度低于夜间,煤火区虚检率偏高。Landsat系列数据以其空间分辨率高、重访周期短、覆盖范围大等优势,在煤田火区动态监测方面具有突出的应用潜力。

In this paper, we use the threshold analysis technique to extract coal fire area of 2002,2007 and 2013 in Wuda coalfield on the basis of Landsat thermal infrared dataset.The results show that the coal fire area in 2007 is nearly doubled of that in 2002 due to extensive coal extraction, however, the coal fire in 2013 is effectively limited because of the extinguishing activities since 2010. Comparisons with the in-situ data manifest the error estimated by remote sensing is about 5% - 10%, and solar radiation in the day leads lower inversion accuracy than the night, which causing higher virtual screening rate. Landsat imageries have important application potential in coal fire dynamic monitoring with its advantage of high spatial resolution, short revisiting cycle and large coverage.