The invention belongs to the technical field of
geophysical inversion, and relates to a
gravity anomaly three-dimensional inversion method based on multi-scale
feature fusion, which comprises the following steps: randomly generating density anomaly bodies with different numbers, densities, sizes and shapes to obtain an underground medium three-dimensional
density model; carrying out forward modeling on the three-dimensional
density model of the underground medium to obtain two-dimensional gravity abnormal data of the
earth surface; a multi-scale
feature fusion model is trained with the underground medium three-dimensional
density model as output and the two-dimensional
gravity anomaly data as input, and the multi-scale
feature fusion model comprises a two-dimensional
encoder, a three-dimensional decoder, a dimension converter and a multi-scale feature fusion device, wherein the dimension converter and the multi-scale feature fusion device are located between the two-dimensional
encoder and the three-dimensional decoder; and inputting actually measured two-dimensional
gravity anomaly data into the trained multi-scale feature fusion model, and performing inversion to obtain a three-dimensional density body constrained by a physical range. According to the method, the expression capability of the multi-scale features of the underground structure is enhanced, and the multi-solution problem and the deep resolution reduction problem of inversion can be relieved.