The present invention discloses a method for constructing a relationship model for identifying
clastic rock lithology, which relates to the technical field of
lithology identification. The method determines the target
lithology type after the initial lithology type is simplified and classified by the
logging characteristics corresponding to the sample
clastic rock classified by the
clastic rock core; and constructs a target relationship model according to the
logging characteristics of the sample clastic rock and the target lithology type of the sample clastic rock. The target relationship model is used to classify and identify at least one mudstone type and sandstone types of different particle sizes. In this way, the complex initial lithology type is simplified to the target lithology type with similar
logging characteristics, and the target relationship model is constructed, so that different lithology types can be classified and identified, reducing the dependence on traditional core sampling, helping to simplify the classification process of lithology identification, and being able to adapt to different geological conditions and environments.