Sediment compositional data for the 2016 Kaikōura Event Bed

Seafloor sediment cores were collected using an Ocean Instruments MC-800 multi-corer across the Hikurangi active subduction margin, off eastern central Aotearoa New Zealand, including samples from several canyons, primarily Kaikōura Canyon, and the Hikurangi Channel and its overbank area. Samples were collected pre- (6 years before) and post- the November 2016 Mw7.8 Kaikōura Earthquake at a range of timescales (i.e., 5-6 days and ~7-10-months, post-earthquake) (Table 1). Push-cores were first analysed using Computerised Tomography (CT) to highlight sedimentary structures and layers, consistent with the turbidite facies designations ascribed to the KEB (Maier et al., 2024). Samples were then analysed for grain-size distributions, total organic matter (TOM), percent particulate organic carbon (POC) and nitrogen (PN) content, carbon and nitrogen stable isotope composition (δ13C, δ15N), conventional radiocarbon age of bulk sediment-associated OC, phytopigments (chlorophyll-a and phaeopigments), and DNA genetic fingerprinting of terrestrial vascular plant materials. The sediment compositional data, except DNA results, from this suite of cores are presented in Table 2. Previous work has also characterised the OC composition in selected KEB samples across the margin using Ramped Pyrolysis Oxidation-Accelerator Mass Spectrometry (RPO-AMS), coupled with Pyrolysis-Gas Chromatography-Mass Spectrometry (Py-GC–MS) techniques (Ginnane et al., 2025; Maier et al., 2025). Details of these sampling and analytical methods can be obtained upon request from the lead author. The data form the basis of a submitted manuscript that is under review (as of October 2026).