Abstract: Four types of more than 20 lithologies are distributed in the third member of Shahejie Formation, the fourth member of Shahejie Formation, and the Mesozoic in the KL16 oilfield of Laizhou Bay Sag in the southern Bohai Sea. This area is rich in volcanic debris, and it is difficult to identify the lithologies distributed in multiple series of strata. Based on the analysis of (sidewall) cores and thin sections, the lithologies were classified and identified by elemental logging, imaging logging, and conventional logging data. The results show that lava and pyroclastic rocks, volcanic debris-rich glutenites, lacustrine carbonate rocks, hybrid sediments and siliceous sandstones can be effectively distinguished by the composition-structure crossplot of natural gamma logging (GR) and deep lateral resistivity logging (RD). A chart was established for identifying the composition and structure of igneous rocks in the study area, which can subdivide lava and pyroclastic rocks into andesite, andesitic volcanic breccia, andesitic tuff, rhyolite porphyry, rhyolite volcanic breccia, and rhyolite tuff. The crossing of neutron log (CNCF) and density log (ZDEN) curves in combination with deep lateral resistivity logging (RD) curve has a good effect on the identification of glutenites, which can be subdivided into poor-mud glutenite, calcite glutenite, tuffaceous glutenite and shaly glutenite. The enrichment section of carbonate rocks in the interbedded lacustrine carbonate rocks and multi-component mixed hybrid sediments can be identified by the crossing of photoelectric absorption cross-section index logging (PE) and acoustic travel time logging (DT) curves, in combination with imaging logging and lithoscanner logging. These understandings can provide a useful reference for the logging identification of complex formations in volcanogenic sedimentary basins, and have good application value.