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International Ocean Discovery Program Expedition 369 recovered a volcanic sequence (Lithostratigraphic Unit VI) at Site U1513 on the eastern Naturaliste Plateau, offshore southwest Australia. We report here the mineralogical composition of the 82.2 m thick volcanic sequence cored in Holes U1513D (24 samples) and U1513E (20 samples) based on X-ray diffraction analysis. The primary minerals preserved in basalt flows and dolerite dikes are plagioclase feldspar and pyroxene, whereas the original olivines have been mostly transformed into secondary phases. Increasing alteration intensity is accompanied by higher amounts of clay minerals (chlorite, kaolinite, interstratified smectite-chlorite, and smectite), iron oxides (magnetite, hematite, and goethite), and likely other secondary minerals associated with serpentinization and sericitization processes. The fine-grained matrix of the volcaniclastic beds contains abundant clay minerals (mainly kaolinite) accompanied by intense hematization. 

International Ocean Discovery Program (IODP) Expedition 369 recovered the first stratigraphically constrained volcanic sequence at Site U1513 on the eastern flank of the Naturaliste Plateau. We report macroscopic and microscopic core description and petrophysical data from this 82.20 m thick volcanic sequence (Lithostratigraphic Unit VI). We present a modified volcanic stratigraphy based on postexpedition examination of the core sections from Holes U1513D and U1513E. The volcanic sequence is divided into nine lithologic units consisting of alternating basaltic flows (Units 1, 3, 5, 7, and 9) and volcaniclastic beds (Units 2, 4, 6, and 8), cut by multiple intrusions.