Abstract：Gravity exploration areas are usually irregular and there is some data vacancy.Missing data must be interpolated before the downward continuation in the wave-number domain.Meanwhile,in order to improve the processing precision,the data needs to be edge-padded to the length satisfied with the fast Fourier transform algorithm.For conventional downward continuations of gravity data,only the downward continuation is considered,or the three steps of interpolation,expansion and downward continuation are executed independently.In this paper,the three ill-posed problems are considered uniformly,and an integration method based on the projection onto convex sets theory is proposed.The integration method uses Gerchberg-Saxton iteration method to interpolate and expand data until a predetermined iteration number is reached,andthen the interpolated and expanded results aredownward continued.A comparison of the proposed method with some classical interpolation,border padding,and downward continuation methods is carried out on model and real gravity data.The results show that the proposed method is simple,easy to be accomplished,and has higher interpolation,edge-padding and downward continuation accuracy.
曾小牛, 李夕海, 刘继昊, 侯维君. 基于凸集投影的重力数据扩充下延一体化方法[J]. 石油地球物理勘探, 2019, 54(5): 1166-1173.
ZENG Xiaoniu, LI Xihai, LIU Jihao, HOU Weijun. An integration of interpolation,edge padding,and downward continuation for gravity data based on the projection onto convex sets. Oil Geophysical Prospecting, 2019, 54(5): 1166-1173.
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