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The Deep Sea Drilling Project Site 464 is located on the northern flank of Hess Rise in the northwest Pacific, with a water depth of 4637 meters. The site's sedimentary sequence consists of three main units: Unit 3 (219-m thick, Albian to Cenomanian age) contains cherts, limestones, and chalk; Unit 2 (53-m thick, Early Cretaceous to late Miocene age) is composed of soft brown clays and pelagic oozes; and Unit 1 (33 m, late Miocene to Pleistocene age) consists of clays, siliceous biogenic muds, and oozes. The sedimentary facies evolve from siliceous biogenic sediments to brown clays, with varying proportions of clays, carbonates, and silica. Authigenic silicates and Fe-Mn oxyhydroxides are present, with trace elements varying depending on the marine environment. Siliceous aggregates in the brown clays are composed of quartz, cristobalite, and zeolites, formed through silification processes. The study of the sedimentary sequence and mineralogical composition provides insights into the diagenetic evolution of silica and the transition between siliceous biogenic oozes and brown clays.