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The Pleistocene Tamala Limestone outcrops for ~1000km along the southwestern Australian coast. Detailed mapping of excellent exposures at Nambung National Park and surrounding areas, together with mineralogical analyses and dating, identified five members: White Desert, Nambung, Stockyard Gully, Pinnacles Desert and Grey members (in stratigraphic order). The two youngest members can be easily recognised because they partly retain the original aragonite and high-Mg calcite mineralogy of the bioclasts (the youngest Grey Member to the greatest extent). Each member consists of an eolian calcarenite/calcrete-microbialite/paleosol cycle. The eolianites were deposited during interglacial highstands (MIS 5, 7, 9, 11 and possibly 13), under the influence of strong south to southwesterly winds that blew the sand well inland and up to over 100m above sea-level. This scenario continued during the Holocene transgression, showing that dune activity in this region was a characteristic of the relatively humid interglacial climates rather than the drier glacial periods. Towards the end of most interglacial episodes, the rainfall was sufficiently high that the dunes were stabilised by vegetation, and there was significant subsoil dissolution of the eolianite, forming a karst surface. In the following glacial climates, laminated microbialites were deposited in the karst voids within some members; in others a calcrete layer is present, probably reflecting a semiarid climate. The paleosols capping each member contain an eolian input of silt and some clay owing to the increased wind activity associated with the glacial climates when they were deposited. The laterally extensive quartzose Cooloongup Sand was deposited on top of the Tamala Limestone during the glacial climate of MIS 2-4, reflecting the low rainfall and strong winds. The quartz sand was derived from dissolution of the eolianites during preceding periods of karstification.