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The Guaymas Basin, in the central Gulf of California, is a marginal ocean basin characterized by active seafloor spreading and high sedimentation rates. It has been the focus of two drilling expeditions, Deep Sea Drilling Project (DSDP) Leg 64 and International Ocean Discovery Program (IODP) Expedition 385. Expedition 385 recovered over 4 km of middle Pleistocene to Holocene core at eight drill sites, providing only simplistic stratigraphic columns that were broadly divided into as many as four lithostratigraphic subunits largely based on diagenetic modifications of sediments (authigenic carbonate and silica). For this study, shipboard sedimentologic descriptions of these subunits were used to create new, more detailed lithostratigraphic columns at an approximately decimeter (core) scale for correlation purposes and sedimentary interpretation. This was accomplished through examination of slabbed core images, visual core description sheets, and a shipboard lithologic database. The new columns provide more detailed downhole variability in lithology. The lithologic classification scheme for Expedition 385 was then integrated with that of sites previously drilled during Leg 64 to translate published visual core descriptions so as to uniformly generate comparable stratigraphic columns for both sets of drill holes. These newly compiled and tabulated data provide a more detailed picture of stratigraphic variation of lithology on a core by core basis across the basin.