| Summary: | In this study, we delve into a newly constructed composite sedimentary sequence obtained from Linnévatnet in western Spitsbergen, covering approximately the last ~2,000 years. Micro-X-ray fluorescence (μ-XRF) results show that calcium constitutes the major component of sediment deposited in the delta-proximal basin, where the sedimentary record was obtained. Percentage of organic material, as determined through loss-on-ignition measurements, exhibits an inverse relationship with calcium and magnetic susceptibility. This implies that the sediment input at the core site is mainly influenced by the alternation of calcium sourced from the carbonates on the eastern valley slopes and coal-bearing sandstone from Linnéelva, which originates from the central valley's main river inflow. Linnéelva primarily receives its water from the snow and glacier meltwaters of Linnébreen, a small valley glacier situated 7 kilometers south of Linnévatnet. Since Linnébreen is underlain by coal-bearing sandstone, the organic content in Linnévatnet's lake sediments can serve as an indicator of glacier activity. We discovered that parameters with annual resolutions, such as calcium and grain size, exhibit strong correlations with temperature estimates derived from nearby Lomonosovfonna's δ18O (the ratio of stable isotopes oxygen-18 and oxygen-16) ice record, as well as broader reconstructions of Northern Hemisphere winter temperatures. Notably, the coarsest grain size, the highest calcium values, and the lowest organic content were observed in recent years, indicating that the influence of glaciers on the sediment input to Linnévatnet is currently at its lowest point in the context of the past millennia. Article: https://doi.org/10.1080/15230430.2023.2223403
|
|---|