College of Geo- Exploration Science and Technology��Jilin University��Changchun 130026��China

Edge detection of potential field interpretation is an important task�� The traditional edge detection methods have poor ability in outlining weak amplitude anomalies clearly�� The resolved edges position is blurred�� We purposed new edge detection methods based on directional eigenvalues of potential field gradient tensor for the causative sources�� In order to balance strong and weak amplitude anomalies simultaneously��we present one normalization method using different orders of vertical derivatives to improve the new filters�� The presented fil- ters were tested on synthetic and real potential field data to verify its feasibility�� All of the results have shown that the new edge detection methods can not only display the sources edges precisely and clearly��but also bring out more geological subtle details��