These data sets compile geochemical and sedimentological information on terrestrial and marine sediments taken from the Yukon coastal plain (Canadian Arctic) and the Beaufort Sea (Arctic Ocean).Terrestrial sediments were taken from active layer and permafrost compartments with a SIPRE corer, drill hammer, spade and probing cylinder between the coastline south-east of Qiqiktaruk – Herschel Island and the adjacent Richardson Mountains. Lagoon surface sediments and short cores were taken with a Van-Veen grab sampler and a percussion corer from Kanivaliuraq – Ptarmigan Bay lagoon. Marine sediments were taken with a gravity corer along transects from the lagoon towards the open ocean (Herschel Basin). All sediments were taken during a spring field campaign in 2016 (April/May) and two summer field campaigns in 2018 and 2019 (July/August).The sediments were analysed for total carbon (TC), total organic carbon (TOC), total nitrogen (TN), OC loading as well as stable carbon and nitrogen isotopes (δ13C-TOC and δ15N-TN, respectively) to characterize organic matter (OM) composition. Grain size distribution and surface area of particles was determined to describe the sedimentological characteristics of the sediments. OC loading was estimated using TOC content and surface area of particles.Furthermore, bulk density, bulk mineralogy, and radioisotopes (total and excess 210Pb, total 137Cs) were measured on lagoon and marine short cores. Mass accumulation and sediment accumulation rates (MAR and SAR, respectively) were calculated. Bulk mineralogy included smectite, chlorite, kaolinite, illite, amphibole, quartz, albite, microcline, calcite, dolomite, pyroxene, pyrite and halite.The aim of the study was to determine transport pathways and biogeochemical cycling of OM at the land-ocean-interface of permafrost coasts. A better understanding of these processes is needed to better constrain the impact of climate warming on carbon pathways along degrading coastlines in the Arctic and the role of lagoon environments and embayments for carbon dynamics. The data sets summarise metadata and geochemical information for terrestrial sediments (Data set 1), lagoon sediments (Data set 2) and marine sediments (Data set 3). Radioisotopic measurements, MAR and SAR are summarized in Data set 4 (lagoon short core) and Data set 5 (marine short core).