Core recovery was poor to very poor throughout the cherty interval, without any of the anticipated carbonate sediment that had been discovered overlying basement basalt at a number of northwest Pacific sites on Cretaceous crust. A number of long-ranging dinocysts were found over this interval, together with more diagnostic taxa such as Operculodinium janduchenei, Habibacysta tectata, Corrudinium harlandii, and. Stlacontarium acqilonium is a long ranging taxon found in all subsequent samples studied to date. Samples taken from sediment recovered between the cherts recovered at Site 1179 were determined to be barren of nannofossils. Lava flows consist of fine grained to coarse grained aphyric basalt.
Alteration is slight to moderate.
Veins are randomly oriented and are filled with calcite and Fe-oxyhydroxides. Oxidative alteration halos commonly surround the veins. Some of the basalts recovered were remarkably fresh for Early Cretaceous material. The magnetic stratigraphy for Site 1179 thus consists of a complete record of virtually all the recognized polarity chrons from mid-Miocene onward. The bottom of core 23H has an approximate age of 17.62 Myr.