Abstract:

The processing and interpretation techniques of high precision magnetic method are applied in deep-layer volcanic rocks prediction of GulongChangjiaweizi faulting-depression in Songliao Basin and the application results are discussed. The magnetic anomalies are produced by the superposition of basement lithology and volcanic rocks, therefore it is very difficult to predict the deep-layer volcanic rocks by applying the conventional high-precision geomagnetic method. The slide-trending and wavelet multi-scale analysis can be a powerful tool for separating the magnetic anomalies of the volcanic rocks, and the analytical signals and vertical derivatives of magnetic anomalies can indicate and identify the lithology of volcanic rocks. This technique can also be applied in the prediction of deep-layer volcanic rocks in other areas.

Key words: Songliao Basin, magnetic anomaly, fault-depression, volcanic rock, anomaly separation, anomaly enhancement