Application of Ground High-Precision Magnetic Measurement in Regional Geological Mapping
The concept of multi-frequency magnetic anomaly is introduced on the basis of previous researches. With comparison of some commonly used filtering methods, the idea of frequency-division by wavelet filtering and the interpolation-cut filtering is put forward. The relation between the frequency-divided magnetic anomaly and lithology is discussed. It is concluded that: 1) since the amounts of information double with frequency-dividing, the information that cannot be recognized from primary data will be extracted; 2) different frequencies give different macroscopical characteristics; 3) a kind of rock is not correlated to only one frequency of magnetic anomaly; 4) the structures of primary data decide the result of frequency-division; 5) the frequency-division of four to five bands will get much more new information; 6) similar to the general magnetic anomaly interpretation, the manual analysis is important in anomaly interpretation after information abstracting; 7) the times of interpolation-cut filtering is the factor of smooth; and 8) the frequency-divided magnetic anomaly can distinguish different kinds of rocks.