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The dataset contains geochemical measurements which quantify the amount and source of carbon in organic matter of sediments from Lake Paringa, New Zealand. Measurements were made on a 6 m sediment core collected in 2015 from the lake bed using a Mackereth corer (PA6m1a). The core was correlated to master core PA1 which has a well-established age-depth model based on accelerator mass spectrometry measurements of the radiocarbon (14C) content of terrestrial macrofossils (Howarth et al., 2016). In addition, soil samples were collected using a soil auger from two elevation transects in westland, New Zealand in 2016 and 2017 (from Mt. Fox and Alex Knob). All sediment samples were freeze dried and ground to homogenise them prior to geochemical analyses. Organic carbon concentration (%) and the stable isotopic composition of organic carbon (δ13C) was measured (Frith et al., 2018) following the removal of carbonate minerals (0.25 M hydrochloric acid for 4 hours at approximately 70 °C) by combustion of sediment at 1,020 °C in a Costech Elemental Analyser coupled via a CONFLO III to a Thermo Scientific Delta V Advantage stable isotope mass spectrometer. Total nitrogen content (N, %) and its isotopic composition (δ15N) was measured by combustion of untreated samples in a Costech Elemental Analyser with a CARBOSORB trap to inhibit large CO2 peaks from affecting measurements. A subset of samples were selected for analysis of the radiocarbon activity (14C, reported as F14C) of bulk organic matter by accelerator mass spectrometry after graphitization. A subset of sediment samples from the lake core and soil samples were selected for the analysis of biomarker abundance and their hydrogen isotope composition. We focused on the extraction of n-alkanes from aliquots of lake sediment (~2 g) using established methods (Wang et al., 2020). These measurements are reported in the dataset as the abundance of n-alkanes (chain lengths C21 to C35) in ug/g of sediment (and sum of chain lengths and ratios - carbon preference index). Finally, the dataset includes outputs of organic matter provenance: modelled elevation and depth, as described in Wang et al., (2020). In the datafile, the sample elevation and depth are provided. The labels for data are as follows. For down core sediment samples from Lake Paringa, they are labelled with the core code (PA6m1), and the sampling interval in centimetres (PA6m1_x). Soil samples from an elevation transect from Mt Fox (MF-YY-a) are labelled with a distinct code for each site (YY) and sub-code for each soil depth (a). Soil samples from an elevation transect of Alex Knob (5.Z.z) are labelled based on sub-site (Z) and soil depth (z).
Geochemical data for the upper 300cm of giant piston core MD04-2832. Core MD04-2832 was collected from the middle basin of Loch Sunart a fjord on the west coast of Scotland from the research vessel Marion Dufresne on the 15th of June 2004. This data resource includes five data sheets: (1) Geochemical data, (2) Bulk radiocarbon, (3) ICP-MS, (4) FRUITS and (5) Age Model. 1. Geochemical data sheet includes Bulk elemental data (Organic Carbon, Nitrogen, C/N ratio, N/C ratio), Isotopic data (δ13C and ẟ15N), Biomarker data (Alkanes, Fatty Acids, GDGT's) and thermosgravimetric data (% labile, recalcitrant and refractory organic matter). 2. Bulk Radiocarbon data sheet includes bulk radiocarbon data for ten sediment samples presented as % modern, 14C Age (years BP), ẟ14C and Δ14C. 3. ICP-MS data sheet includes metal data associated with mining activities within the fjords catchment. Data includes Zinc (Zn), Lead (Pb), Copper (Cu), Barium (Ba), Aluminium (Al) and elemental ratios of these metal normalized with Al concentrations. 4. The FRUITS data sheet contains the outputs from the FRUITS Bayesian isotopic mixing model (Fernandes et al., 2014) used to constrain the source (terrestrial vs marine) of the organic carbon found at site MD04-2832. The model used bulk elemental ratios (N/C), Isotopic (δ13C and ẟ15N) and biomarker data (GDGT - BIT Index) to calculate the terrestrial and marine OC fraction from each downcore sample. 5. The Age Model datasheet contains the age model produced by the BACON software package (Blaauw and Christen, 2011). The age model was developed with a combination of shell/foraminifera radiocarbon dates and radiometric dating (210Pb and 137Cs). Further details on the data can be found in Smeaton, C., Cui, X., Bianchi, T.S., Cage, A.G., Howe J.A., Austin, W.E.N., (2021), The evolution of a coastal carbon store over the last millennium, Quaternary Science Reviews.