Over the last few years, industry and academia have been shifting towards computer aided models for seismic interpretation because manual labeling and salt dome delineation is becoming very time consuming and labor intensive as the volume of seismic data is in the order of tera-bytes. In this paper, we have proposed an edge-based active contour with an arc length penalty using level set implementation for interpreter-assisted salt dome segmentation. We have designed an edge function and studied the effect of varying different active contour parameters on salt dome boundary detection. Experimental results show the effectiveness of proposed method on the real seismic dataset of F3 block in the North Sea. We have also compared our results with other state of the art methods of salt dome detection and the ground truth which show that active contours are very good candidate for segmenting salt dome.