Data report: middle Miocene to Pliocene planktonic foraminiferal biostratigraphy of the northern part of the Shikoku Basin, IODP Expedition 322 Site C0012

Abstract

Planktonic foraminifers collected from Site C0012 drilled during Integrated Ocean Drilling Program Expedition 322 in the northern part of the Shikoku Basin, northwestern Pacific Ocean, were examined to establish a reference biostratigraphy of the Nankai Trough Seismogenic Zone. With the exception of several barren intervals, planktonic foraminifers are present throughout the cores at the studied site. Nineteen biohorizons are recognized at the studied site. Among these, four biohorizons are refined and fifteen are newly detected after the onboard study. The studied sequence correlates with Zones M7 to PL4, ranging in age from middle Miocene to Pliocene. A new age-depth plot of the studied site is presented on the basis of foraminiferal data from this study combined with nannofossil biohorizons determined by the onboard study.