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Data inventory of the varve database (VARDA): Sediment profiles, chronologies, radiocarbon dates, tephra layers and varve thickness data

The data collection presented here is the data inventory of the VARved sediments DAtabase (VARDA) in version 1.3. VARDA is freely accessible and was created to assess outputs from climate models with high-resolution terrestrial palaeoclimatic proxies. All data were collected as raw data from freely available online sources, either from online data repositories (Pangaea, NOAA, and Neotoma) or data archives within the supplementary materials section of online publications. The current data collection consists of meta information and datasets from 95 lake archives. The data is stored in JSON and CSV format. All datasets are stored as individual files (JSON and CSV). Each dataset consists of samples for either i) chronologies; ii) radiocarbon data; iii) tephra layer; or iv) varve thickness data. Meta-information for each dataset is summarized in one csv and seven JSON files. Additional paleoclimate proxy data will be provided in forthcoming updates of VARDA. The data collection of VARDA Version 1.3 is provided as an archive (.tar.gz) with the following files/folders. Overview lists with categories, cores, countries, datasets, lakes and publications included in VARDA. Each item in the lists is cross-referenced with the other files via its $ref property which includes the corresponding list index or the dataset's UUID (from the VARDA database). The data points themselves are provided in the "records" folder and named with each dataset's UUID respectively. For more information on the data structure please read the "index.html" file included in the archive and available on the DOI landing page. VERSION HISTORY: 26 July 2020: release of Version 1.3: 1. Fix issues with chronologies in the export 2. Provide recalculated machine readable error estimates 3. Correct some metadata values (e.g. core labels) 5 March 2020: release of Version 1.1 1. Added fields: "distributor" - Field containing name of data distributor "url" - Field containing DOIs and URLs, which lead to the original data publications 2. Correction of publication DOIs in 9 cases The version 1.0 is available in the "previous-versions" subfolder via the Data Download link. The index file is unchanged.

OGS Core Logging Lab - logging sediment cores in Lago Argentino (Brazo Sur), Argentina

The spectacular water outburst occurring semi-periodically when the ice-dam formed by the external front of the Perito Moreno glacier collapses, is one of the most attracting events in the UNESCO ‘Parque Nacional Los Glaciares’ of southern Patagonia. These occurrences have been documented since 1936. Instead, evidence of previous events has been only indirectly provided by dendrochronology analysis. Four sediments cores have been collected on coastal soil in 2017, analysed by X rays, HR photography and Magnetic Susceptibility. The radiographies of these cores allowed to identify lake floodings deposits due to glacier readvance over the coastal soil related to the collapse of the Perito Moreno ice-dam. In November 2018, 10 undisturbed sediment gravity cores were collected within a small inlet of Brazo Sur, that is, the southern arm of Lago Argentino, at water depths ranging from 10 to 6 m using a 4.5 cm diameter gravity corer ‘KC Kajak Sediment Sampler’ Model 13.030. The length of these cores varies from 45 to 65 cm. X rays, HR photography and magnetic susceptibility provide the first evidence of an abrupt change in the stratigraphic record found at variable depths of 14–18 cm from the top of the cores, marked by a hiatus spanning ca. 3200 years, separating planar-laminated sediments below from an alternation of erosional and depositional events above it, indicating recurring high-energy conditions generated by the emptying of the lake basin, as well as ash layers observed in the longest cores. Radio carbon data collected on three of these cores record ice-daming in the Little Ice age, at 324-266 cal yrs BP. These well-preserved stratigraphic records highlight the key role of glaciolacustine deposits in reconstructing the glacial dynamics and palaeoclimate evolution of a glaciated region.

Major Element and Trace Element Compositions of Tephra Layers Found in European Varved Lake Records

This database contains major and trace element compositions of European tephra and metadata for the datasets and lakes they were found in. It was created by collecting data from scientific literature to support the synchronisation of annually-resolved lake sediment records during the Last Glacial Interglacial Transition (25 ka BP to 8 ka BP). 49 individual tephra layers across 19 varved lake records have been included, with Lago di Grande Monticchio being the largest contributor of geochemical data with 28 layers. The Vedde Ash and Laacher See tephra are the most common layers, being found in 6 different varved records, and highlight the potential of refining the absolute age estimates for these tephra layers using varve chronologies and for synchronising regional paleoclimate archives. This project is the first stage in a 5-years plan funded by the Past Global Changes (PAGES) Data Stewardship Scholarship to incorporate a global dataset of tephra geochemical data in varved sediment records. Further stages of this project will focus on different regions and timescales.

Drilling Overdeepened Alpine Valleys (DOVE) - Operational Dataset of DOVE Phase 1

The overarching goal of the Drilling Overdeepened Alpine Valleys (DOVE) project will be to date the age and extent of past glaciations. Formerly-glaciated areas are often characterized by deeply incised structures, often filled by Quaternary deposits. These buried troughs and valleys were formed by glacial overdeepening, likely caused by pressurized subglacial meltwater below warm-based glaciers. Results of this drilling campaign, supported by new dating technologies, will further provide critical data on 'how' and 'at which rate' glacial erosion affects such mountain ranges and their foreland. These processes are also of fundamental importance for evaluating the safety of radioactive waste disposal sites, which are planned in areas of former glaciations. Moreover, results of this project will fill gaps in the knowledge of paleoclimate and atmospheric circulation patterns during past glacial epochs and how these patterns affected ice build-up. The operational data sets include the drill core documentation from the mobile Drilling Information System (mDIS), full round core scans, MSCL data sets, a preliminary core description and the geophysical downhole logging data that were acquired during and subsequent to the drilling operations. All downhole logs and core depth were subject to depth correction to a common depth master (cf. operational report for detailed information). The data are described by two scientific reports, the Operational Report (https://doi.org/10.48440/ICDP.5068.001) and the Explanatory Remarks on the Operational Datasets (https://doi.org/10.48440/ICDP.5068.002).

Paleosediment- and model-derived data used for the reconstruction of environmental conditions during the Holocene at the Bulusan Lake, Philippines

This data publication contains the datasets generated in a study aiming at reconstructing paleoclimatic conditions during the late Holocene in northern Philippines. The data come from samples taken from sediment lakes retrieved from Bulusan Lake on the Luzon Island, Philippines. On these samples we measured the stable-hydrogen-isotopic composition of terrestrial-lipid biomarkers to reconstruct ENSO dynamics and past hydrological conditions, pollen data to reconstruct past vegetation, and magnetic susceptibility measurements of the sediment cores to reconstruct past erosion rates. This is complemented with isoGSM2 data to constrain modern hydrological conditions. The data was generated between 2013-04 and 2020-9. The data files are provided in Excel and tab-delimited text versions.

OSG Logging Data - Lake Junín Drilling Project, Perú - 22-JUL-18-AUG-2015

The Lake Junín Drilling Project, co-funded by the International Continental Scientific Drilling Program, ICDP, aims to provide a continuous paleoclimate record from lacustrine sediments, and to reconstruct the history of the continental records covering the glacial-interglacial cycles spanning more than 500 kyr. Lake Junín, also known as Chinchaycocha, is a shallow (maximum water depth of 12 m), inter-mountain high-elevation (at 4100 m a.s.l.) lake in the inner-tropics of the Southern Hemisphere that spans 300 km2 in the tropical Andes of Peru. Drill cores were recovered during summer 2015 from three drill sites on the lake. After the completion of coring operations in each hole, downhole logging measurements were performed in five of the 11 boreholes (1A, 1C, 1D, 2A and 3B) by the Operational Support Group of ICDP at GFZ Potsdam (OSG). The OSG logging data from Lake Junín Drilling Project is given here in three data formats. For each of the five boreholes all processed logging data are comprised in one composite logging data set, this set is given here both in ASCII text and in WellCAD format. Additionally, the raw sonic waveform data are in LIS format: • Composite logging data in ASCII text files (.txt) • Composite logging data in WellCAD format (.wcl) • Sonic raw data (waveforms) in LIS format (.lis) Detailed description is provided in the associated data description file.

Data supplement to: A high-resolution geomagnetic relative paleointensity record from the Arctic Ocean deep water gateway deposits during the last 60 ky

This data publication includes the paleomagnetic and rock magnetic dataset from two Calypso giant piston cores collected at the crest of the Bellsund (GS191-01PC) and Isfjorden (GS191-02PC) sediment drifts during the Eurofleets-2 PREPARED cruise, on board the R/V G.O. Sars (Lucchi et al., 2014). These sediments drift are located on the eastern side of the Fram Strait (western Spitsbergen margin).The dataset gave the opportunity to define the behavior of past geomagnetic field at high latitude and to constrain the palaeoclimatic events that occurred in a time framework spanning Marine Isotope Stage (MIS) 3 to Holocene (Caricchi et al., in press). The data are provided as raw data in .dat format and interpreted data in .xlx and tab-delimited text formats. The raw data files can be opened using a text-editor, MS Excel or equivalent software.The interpreted data are presented as a metadata table with definitions of the column heads and 5 individual tables with the content:- Metadata: definition of columns heads- Rock Magnetic-Paleomag Data 01: down-core variation of rock magnetic and paleomagnetic parameters [k (10E-05 SI); ARM (A/m); ARM/k (A/m); MDF (mT); ΔGRM/ΔNRM; NRM (A/m); MAD (°); Incl PCA (°); Decl PCA (°)] for Core GS191-01PC- Rock Magnetic-Paleomag Data 02: down core variation of rock magnetic and paleomagnetic data [k (10E-05 SI); ARM (A/m); ARM/k (A/m); MDF (mT); ΔGRM/ΔNRM; NRM (A/m); MAD (°); Incl PCA (°) Decl PCA (°)] for Core GS191-02PC- Cores Correlation: Depth of Core GS191-02PC and depth of Core GS191-02PC correlated to Core GS191-01PC, NRM (A/m); ARM(A/m) and RPI down-core variations for core GS191-02PC; Depth of Core GS191-01PC NRM (A/m); ARM(A/m) and RPI down-core variations for core GS191-01PC; tie points values.- Age Model 01: age model for Core GS191-01PC- Age Model 02: age model for Core GS191-01PC

Supplementary material to: A refined age calibrated paleosecular variation and relative paleointensity stack for the NW Barents Sea: implication for geomagnetic field behavior during the Holocene.

This dataset includes paleomagnetic and rock magnetic analyses from four sediment cores collected on continental slope of Storfjorden and Kveithola trough‐mouth fans (western Spitsbergen margin, southern Svalbard archipelago). In detail, piston core SV-04 was collected during the Spanish SVAIS cruise on board the BIO Hespérides (Longyearbyen, July 29 – August 17, 2007); gravity cores EG-02 and EG-03 were collected during the EGLACOM cruise on board the RV OGS-Explora (Kristinsund, July 07 – August, 2008) and gravity core GeoB17603-3 was collected during the MSM30-CORIBAR cruise on board the RV Maria S. Merian (Tromsø, July 16 – August 15, 2013).The dataset gave the opportunity to reconstruct variation of past geomagnetic field at high latitude and to refine the age-calibrated Holocene PSV and relative paleointensity (RPI) stack curves derived from marine sedimentary cores retrieved in the Northwestern Barents Sea (NBS). Data are presented as one metadata table with definitions of the column heads and four tables with the data on the measured rock magnetic and paleomagnetic parameters and 3 tables with the results of data analyses and elaboration.List of tables is as follows:1) Metadata: definition of columns heads;2) GeoB17603-3: down-core variation of rock magnetic and paleomagnetic parameters [k (10E-05 SI); ARM (A/m); MDF (mT); NRM (A/m); MAD (°); Incl PCA (°); Decl PCA (°)] for Core GeoB17603-3;3) EG02: down-core variation of rock magnetic and paleomagnetic parameters [k (10E-05 SI); ARM (A/m); MDF (mT); NRM (A/m); MAD (°); Incl PCA (°); Decl PCA (°)] for Core EG02;4) EG03: down-core variation of rock magnetic and paleomagnetic parameters [k (10E-05 SI); ARM (A/m); MDF (mT); NRM (A/m); MAD (°); Incl PCA (°); Decl PCA (°)] for Core EG03;5) SV04: down-core variation of rock magnetic and paleomagnetic parameters [k (10E-05 SI); ARM (A/m); MDF (mT); NRM (A/m); MAD (°); Incl PCA (°); Decl PCA (°)] for Core SV04;6) Cores Correlation: GeoB17603-3 depth (cm) and ARM (A/m) down-core variations for core GeoB17603-3 (master core); EG02 depth (cm), EG02 depth transferred to GeoB17603-3 depth (cm), ARM (A/m) down-core for core EG02 and correlation tie points; EG03 depth (cm), EG03 depth transferred (cm), ARM (A/m) down-core and correlation tie points; SV04 depth (cm), SV04 transferred to GeoB17603-3 (cm), ARM (A/m) down-core for core SV04 and correlation tie points;7) Age model: age model for Core GeoB17603-3; EG02; EG03; SV04; 8) NBS stack: paleomagnetic inclination, declination and RPI variations for NBS stack. In order to define high-resolution correlation between the cores the along-core variation of rock magnetic and paleomagnetic parameters (Sagnotti et al., 2011; Caricchi et al., 2018) have been integrated with the distribution of characteristic lithofacies (Lucchi et al., 2013), and the available age constraints (Sagnotti et al., 2011; Caricchi et al., 2018). Core to core correlation has been reconstructed by means of the StratFit software (Sagnotti and Caricchi, 2018), which is based on the Excel forecast function and linear regression between subsequent couples of selected tie-points.The data are presented as one Excel sheet with seven tables and in tab-delimited ASCII format in the zip folder: 2020-002_Caricchi-et-al_data-txt.zip.

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