GAO Jing-gang1, XUE Chun-ji3, WU Gan-guo3, et al. Method of Fast Extracting Alteration Remote Sensing Abnormal Information Based on Knowledge and Prospecting Application[J]. Journal of Remote Sensing, 2008, (1): 186-192. DOI: 10.11834/jrs.20080124.
The new discovered copper mineralized zone in Halasu region
Xinjiang kalaxiange mineralization belt
was selected as the case study in order to fast extract ETM+ mineralization alteration remote sensing anomaly.First of all
the paper discussed the geological background
geophysical and geochemical anomaly characteristics of this area
aggregated metallogenic regularities
then
compared the features of remote sensing data.Though choosing ETM data sources
we achieved geological
geophysical
geochemical data processing and remote sensing image enhancement processing.Spectrum characteristics of known alteration distribution area and geologic setting
six(bands band 1—5 and 7) of alteration rock of ETM+ image and the enhanced image(ratio image
the principal component analysis image)
iron-stained anomaly and hydroxyl anomaly were analyzed.Spectrum knowledge to differentiate alteration rock from mining region strata was discovered.By introducing the standard error based on TM4<120
we known that the brightness value of phyllic rock was 75.6<TM5/7<87.3
the propvlitization altered rock 64.2<PC4-H<73.42.By the use of the mineralization geological feature of mining region and typical ore deposit mineralization model
we could establish the remote sensing geology mineral prospecting model
and then
the remote sensing geology ore-control characteristic was investigated.The middle-bottom basalt and augitophyre
in the middle Devonian Beita mountain group
were the main rock of the porphyry mineralization within the copper(or molybdenum) belt.As a result
the abnormal information model of extracting alteration remote sensing based on ETM+ image has been developed.Additionaly
the alteration remote sensing abnormal information could be extracted by the expert classifier model of ERDAS IMAGING V8.7.Based on the result we can combine geology with remote sensing image processing.Although the establishment of the regulation was manual
whereas at present
the geological expert system theory was not yet ripe
such model in this field has opened up a new development path.Through actual verification
it proved that the results had good correspondence with the actual condition
and the copper mineralization belt had been discovered.This model provides reference to geological investigation and prospecting for copper mines in those area with the similar geologic background to the southern margin of Kalaxiange region