摘要
在地表能量辐射平衡理论分析的基础上,从岩石热传导、土壤热传导以及煤层气储层影响热导率等方面分析了地下热传导,探讨了地球内部热量传递导致地表温度异常的原因。选择河南焦作煤层气富集区作为热红外遥感监测靶区,运用ASTER热红外遥感数据进行温度反演。首先利用大气辐射传输模型MODTRAN 4进行大气校正获得大气透过率,然后根据NDVI计算地表比辐射率,最后采用分裂窗简化算法反演地表温度。结果表明:研究区温度反演最低为296.62 K,最高为302.67 K,部分研究区呈现显著温度异常。通过分析该区域温度异常的不同原因,注意到富含煤层气对应的靶区呈现温度异常,根据地下热传导机理,据此推断该靶区温度异常是由于地下煤层富含煤层气从而导致地下热导率低于周围地层的热导率所致,该结论仍需要应用其他手段进一步验证。
Based on the analysis of land surface energy-radiation balance theory, the process of underground heat conduction is analyzed from aspects of rock/soil heat conduction capability and influence over rock thermal conductivity caused by coal-bed methane （CBM）. The reasons of land surface temperature （LST） anomalies caused by the heat conduction from the depth of earth are discussed. LST at coal bed methane district is retrieved based on the ASTER data acquired over high CBM density area of Jiaozuo, Henan Province. The retrieved steps is as following： Firstly the atmosphere transmittance is simulated through MODTRAN 4 and land surface emissivity is calculated from NDVI. Then LST of study area is retrieved through split-window algorithm. The result demonstrates that the maximum LST is 302.67 K and the minimum is 296.62 K. LST anomalies can be easily identified in some area. The causes of LST anomalies area are analyzed and it can be deduced that the main reason of LST anomalies of study area is underground thermal conductivity anomalies caused by high CBM density. The conclusion needs further verification through other methods.
出处
《北京大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2009年第1期137-143,共7页
Acta Scientiarum Naturalium Universitatis Pekinensis
基金
国家高技术研究发展计划专项经费(2006AA06Z233)
北京市自然科学基金(4082013)资助
关键词
地表温度异常
地下热传导
煤层气
热红外遥感
land surface temperature anomalies
underground heat conduction
coal-bed methane
thermal remote sensing
