Varve-dated depositional history since 1800 CE reconstructed using physical and chemical sediment parameters derived from a gravity core of proglacial Lago Frías, North Patagonian Andes, Argentina

DOI

Physical (CT scanning, magnetic susceptibility, dry density, water content, grainsizes) and chemical parameters (XRF core scanning, CNS analysis) in combination with radiometric dating (14C, 137Cs, 210Pb) and microfacies analysis characterize the short (1.35 m) sediment record from proglacial Lago Frías (Rio Negro Province, Argentina) as annually laminated (varved) interrupted by two events. These events relate to the eruption of Volcán Calbuco (1893 CE), which produced a distinct 1 cm-thick tephra layer, and to a mass movement deposit (53 cm) with an erosive base linked to the Great Chilean Earthquake (1960 CE). The radiometric chronology is distinctly refined by varve chronology. Proglacial varves were analysed by greyscale variations of high-resolution radiographies obtained by CT scanning and employing the BMPix and PEAK tools (Weber et al., 2010) for normalising, recognition and counting of these clastic laminations. Microfacies analysis was utilised for verification. Correlation of varve thickness with instrumental meteorological data since 1960 CE provides a weak correlation with instrumental summer temperature data, while the floating chronology from 1803-1893 CE does not correlate with summer temperature reconstructions based on tree-ring data. Nevertheless, this lacustrine sediment record provides an environmental reconstruction for the last two centuries with valuable insights into climatically-controlled depositional processes (Zolitschka et al., 2026, subm.).

Identifier
DOI https://doi.org/10.1594/PANGAEA.992634
Related Identifier References https://doi.org/10.1029/2009GC002611
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.992634
Provenance
Creator Zolitschka, Bernd ORCID logo; Gebhardt, Andrea Catalina ORCID logo; Gogorza, Claudia ORCID logo
Publisher PANGAEA
Publication Year 2026
Rights Creative Commons Attribution 4.0 International; https://creativecommons.org/licenses/by/4.0/
OpenAccess true
Representation
Resource Type Bundled Publication of Datasets; Collection
Format application/zip
Size 4 datasets
Discipline Earth System Research
Spatial Coverage (-71.796 LON, -41.054 LAT)