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Radiometric Dates from the South American Andes and Adjacent Areas: A Compilation - part 2 sedimentary rocks

A compilation of 90,688 published radiometric dates for sedimentary rocks from the South American Andes and adjacent parts of South America have been tabulated for access by researchers via GEOROC Expert Datasets. The compilation exists as a spreadsheet for access via MS Excel, Google Sheets, and other spreadsheet applications. Initial igneous compilations were utilized in two publications by the author, Pilger (1981, 1984). The compilations have been added to in subsequent years with the metamorphic and sedimentary compilations separated in the last few years. Locations in latitude and longitude are largely taken from the original source, if provided, with UTM locations maintained and converted; in some cases, sample locations were digitized from electronic maps if coordinates were otherwise not available. Analytical results are not included to prevent the files from becoming too large. The existing compilation incorporates compilations by other workers in smaller regions of the Andes. References to original and compilation sources are included. While I am updating reconstructions of the South American and Nazca/Farallon plates, incorporating recent studies in the three oceans, for comparison with the igneous dates for the past 80 m. y., it is hoped that the spreadsheets will be of value to other workers. Reliability: In most cases the data have been copy/pasted from published or appendix tables. In a few cases, the location has been digitized from published maps; the (equatorial equidistant) maps were copied into Google Earth and positioned according to indicated coordinates, with locations digitized and copied/pasted into the spreadsheet. (It is possible that published maps are conventional Mercator-based, even if not so identified, rather than either equatorial equidistant or Universal Transverse Mercator; this can be a source of error in location. For UTMs, the errors should be minor.) Duplicates are largely recognized by equivalent IDs, dates, and uncertainties. Where primary sources have been accessed, duplicate data points in compilations are deleted. (Analytic data are NOT included.) This compilation is part of a series. Companion compilations of radiometric dates from igneous and metamorphic rocks are available at https://doi.org/10.5880/digis.e.2023.005 and https://doi.org/10.5880/digis.e.2023.007, respectively.

Biomarker concentrations of peat core from Beerberg peatland (Central Germany)

Biomarker concentrations of modern vegetation samples from Beerberg peatland (Central Germany)

Plant macrofossil counts of peat core from Beerberg peatland (Central Germany)

Pollen counts of peat core from Beerberg peatland (Central Germany)

Radiocarbon dating of peat core from Beerberg peatland (Central Germany)

Age-depth model of peat core from Beerberg peatland (Central Germany)

Carbon and nitrogen concentrations and their stable isotope values of peat core from Beerberg peatland (central Germany)

Paleobotanical and biomarker records over 2600 years from Beerberg peatland (Central Germany)

The late Holocene development of a raised ombrotrophic peat bog in the Thuringian Forest in Central Germany was investigated using pollen, plant macrofossils, lipid biomarker, elemental, and radiocarbon analyses. In October 2019, a 3.4 m core was recovered from the Beerberg peatland located in the Vessertal-Thuringian Forest Biosphere Reserve. Radiocarbon dating and a resulting age-depth model indicated that the age of the peatland is ca. 2600 yr BP. The purpose of the study was twofold: establishing a paleovegetation record with a reliable chronology for the Thuringian Forest and comparing the results of the pollen and plant macrofossil analyses to that of the lipid biomarker analysis to determine what additional insight the biomarkers could provide. Along with the counting of pollen and plant macrofossils, the carbon and nitrogen concentrations and their stable isotope values were measured from the bulk samples via elemental analyzer, and the absolute concentrations of n-alkanes, n-alkanols, and n-fatty acids were measured by gas chromatography flame ionization detection. The radiocarbon dates were measured by Accelerator Mass Spectrometry. Modern plant samples were also collected from the peatland during sampling, separated into leaf, stem, and root tissue as much as was possible, and the absolute concentrations of the n-alkanes, n-alkanols, and n-fatty acids were measured for each plant part.

Macrofossil data from selected samples of the Last Glacial at Füramoos, Southern Germany

Macrofossil data from selected samples of the MIS 2-4 period from Füramoos, Southern Germany. The data are used to augment the palynological dataset of the same study.

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