基于ALI数据的柴达木油气区含铁矿物制图

烃类微渗漏造成的油气藏上方红层褪色是遥感间接找油气的重要标志之一，因此，在油气遥感勘探中，含铁矿物的分布制图和铁异常信息的提取至关重要。作为新一代的多光谱图像，ALI（Advanced Land Imager）和ETM+图像相比，光谱分辨率有了很大提高，它在0.4~1.3 μm波长范围内有7个波段，可以有效地反映出不同含铁矿物在此波长范围内独特的光谱特征，可以用于含铁矿物制图和铁异常信息提取。本文选取有天然气分布的柴达木盆地东部三湖地区为研究区，对ALI图像运用光谱角度制图方法进行含铁矿物分布制图。

THE MAPPING OF FERRIFEROUS MINERALS BASED ON ALI IMAGERY IN QAIDAM GAS-OIL AREA

The bleach of red beds above the oil and gas reservoirs caused by the hydrocarbon microseepage is one of the usual indicators in indirect search for oil and gas by remote sensing technology. Therefore, the mapping of ferriferous minerals and the information extraction of iron anomalies play an important role in oil and gas remote sensing exploration. As a new generation of the multispectral image, the spectral resolution of ALI (Advanced Land Imager) has a great improvement compared with the ETM+ imagery. ALI has six bands in the 0.4~1.0μm wavelength region and can represent special spectral characteristics of ferriferous minerals in the 0.4~1.0μm region, so it can be used for the mapping of ferriferous minerals and the information extraction of iron anomalies. In this paper, the three-lake region of Qaidam basin was chosen as the study area, in which gas reservoirs are developed. An ALI image and the spectral angle mapping (SAM) method were used to map the distribution of ferriferous minerals, with a good result obtained. Based on the mapping result, the paper has discussed the spatial relationship of the ferriferous minerals to gas anomaly and gas distribution.