以SiO2 含量为辅助因子的ASTER 热红外遥感硅化信息提取
Silicification Information Extraction Based on the Content of Si〇2 from ASTER TIR Data

硅化蚀变是岩石矿物蚀变中一种重要的矿化蚀变类型,与很多金矿的形成有着密切的关系,且硅化信息常作为野外重 要的找矿标志.通过分析硅化蚀变矿物在先进星载热发射和反射辐射仪(advancedspacebornethermalemissionandreflection radiometer,ASTER)热红外波段的光谱特征,依据硅化作用与SiO2 含量间的关系,选取了SiO2 含量作为提取硅化信息的辅 助因子,提出了ASTER热红外遥感硅化信息提取方法.以内蒙古二连浩特市北部地区为例,完成了该地区硅化信息提取工作. 通过野外实地勘察验证,发现在39个野外实地硅化蚀变采样点中33个采样点在蚀变图像中得到验证,精度达到86.14%.
Silicic alteration, an important alteration type among minera1 rock alteration, has c1ose relationship with the forma- tion of severa1 gold mines and it has often been treated as symbo1 for geo1ogica1 prospecting in the field. This paper proposes a method for the silicification information extraction through analyzing the ASTER(advanced spaceborne therma1 emission and reflection radiometer) TIR spectra1 characteristics of silicification alteration minerals and selecting the content of Si02 as an ac- cessory factor based on the relationship between silicification and the content of Si02. The method was applied in northern er- 1ianho1 cily of Inner Mongolia and the silicification informalion of study area was extracted. Bylhe field survey, 33 of the39 si- 1icification sampling sites have been verified, with an accuracy of 86.14%