Foreland basin alluvial fan fine description and prediction method

The present invention provides a foreland basin alluvial fan fine description and prediction method. The method comprises a step of establishing a foreland basin alluvial fan geological model, a step of establishing the stratigraphic framework of an alluvial fan, a step of carrying out seismic facies and attribute inversion to delineate the plane distribution range of an alluvial fan, a step of carrying out three-dimensional electrical inversion to divide the phase band boundary of the alluvial fan of each period, carry out the fine identification of internal lithology and lithofacies, and determine the spatial distribution characteristics of the lithology and lithofacies, and a step of applying OpenDtect software to analyze the alluvial fan vertical evolution and establishing the deposition model of a study area alluvial fan. The method provided by the invention is mainly based on the sedimentology theory and the geological model foundation established by alluvial fan exposure investigation, logging, seismic, electrical method and other materials are fully utilized, the means of logging geological interpretation, seismic sequence analysis, seismic facies interpretation, attribute analysis and electrical method interpretation are integrated, and each phase band of the alluvial fan and the internal lithology and lithofacies spatial distribution characteristic are effectively identified.