Comparative 14C and OSL dating of loess-paleosol sequences to evaluate post-depositional contamination of n-alkane biomarkers
Research output: Contribution to journal › Research article › Contributed › peer-review
Contributors
Abstract
There is an ongoing controversial discussion as to whether n-alkane lipid biomarkers - and organic matter of loess in general - reflect a synsedimentary paleoenvironmental/climate signal or whether they are significantly affected by postdepositional contamination, for example related to root and rhizomicrobial activity. In order to address this issue at our study site (the Middle to Late Weichselian loess-paleosol sequence Gleina in Saxony, Germany), we determined and compared radiocarbon ages of bulk n-alkanes and sedimentation ages, as assessed by optically stimulated luminescence (OSL) dating. The bulk n-alkanes of the four dated samples yielded calibrated 14C ages ranging from 24.1 to 49.7 cal ka BP (95.4% probability ranges). While the three uppermost n-alkane samples are well within the range or even slightly older than the OSL-inferred sedimentation ages, the lowermost n-alkane sample is slightly younger than the OSL ages. There is hence little or no evidence at our study site for n-alkanes in loess-paleosol sequences being significantly contaminated by deep subsoil rooting or microbial processes. We propose a 14C isotope mass balance calculation for estimating such contaminations quantitatively. Radiocarbon dating of bulk n-alkanes might have great potential for Quaternary research, and we encourage further comparative 14C and OSL studies.
Details
Original language | English |
---|---|
Pages (from-to) | 180-189 |
Number of pages | 10 |
Journal | Quaternary Research |
Volume | 87 |
Issue number | 1 |
Publication status | Published - 1 Jan 2017 |
Peer-reviewed | Yes |
External IDs
Scopus | 85040787704 |
---|---|
ORCID | /0000-0002-9586-0390/work/170107050 |
Keywords
Sustainable Development Goals
ASJC Scopus subject areas
Keywords
- Biomarker, n-alkane, OSL Dating, loess, Pleistocene, 14C dating