Affect of configuration parameters of geobody on regularization downward continuation imaging by successive layer optimization

Regularization downward continuation imaging by successive layer optimization (DCSLO) can be used to study the geometrical configuration and physical distribution of geological body(geobody). Due to possible similar features of potential fields for some bodies of different geometrical configurations, the downward continuation imaging is of no-uniqueness. From spectral study of 4 basic configurations of geological bodies and parameter selection for optimum downward continuation for the 35 gravity models of different configurations, a regressive formulas between configuration parameter and shape correction coefficient is obtained and consequently a configuration filter operator is proposed. With the configuration filter operator the DCSLO will enhance the imaging accuracy of geometrical center of complex geobody. A field example of DCSLO for gravity and magnetic data in FengSunChang area in Western Sichuan is given. With the configuration filter operator determined by the seismic structures and the regressive formulas, the DCSLO imaging is consistent with the main geometrical characteristics of the seismic deep structures and overall density logging data. This verified the applicability and effectiveness of the configuration filtering in DCSLO imaging.