Method and system for identifying dense limestone lithofacies

The invention discloses a method and system for identifying dense limestone lithofacies. The method comprises the following steps: step one, pre-processing logging data; step two, on the basis of coredata, geological data and pre-processed logging data, determining a sedimentary cycle and an interface of each small layer on a single well and acquiring fine small-layer grillwork of the whole workarea; step three, constructing a lithology identification plate based on the core data and logging data and interpreting the logging data to obtain a dense limestone reservoir single-well lithofaciesidentification result; step four, according to the refined small-layer grillwork and the single-well lithofacies identification result, extracting the dominant lithofacies inside each small layer andcarrying out interpolation calculation in respective small-layer grillwork by various ways to obtain dense limestone lithofacies horizontal distribution maps; and step five, on the basis of the regional geological knowledge and