TY - JOUR
T1 - Holocene sedimentology in an isolation basin in the Larsemann Hills, East Antarctica
AU - Mahesh, B. S.
AU - Nair, Abhilash
AU - Ghadi, Pooja
AU - Warrier, Anish Kumar
AU - Mohan, Rahul
N1 - Funding Information:
We thank the Secretary-Ministry of Earth Sciences, New Delhi and Director, NCPOR, for their encouragement and support under the project ?Past Climate and Oceanic Variability?. We thank Pozna? Radiocarbon Laboratory, Poland for measuring the AMS 14-C dates. The authors thank the Indian Antarctic Program and members of the 36-Indian Scientific Expedition to Antarctica for their help in our field campaign. We thank the two anonymous reviewers for their valuable suggestions and insights in interpreting the data and improving the manuscript. This is NCPOR contribution No. J-23/2021-22.
Publisher Copyright:
© 2021 Elsevier B.V. and NIPR
PY - 2021/12
Y1 - 2021/12
N2 - Holocene paleoenvironmental changes along the East Antarctic margin have been reconstructed using marine and lake sediment cores. Isolation basins in the coastal ice-free regions offer continuous sedimentary sequences to reconstruct marine-freshwater transitions and its environmental changes. In this study, we present the grain size (sand-silt-clay) and organic matter variations in a 51 cm radiocarbon-dated sediment core from Pup Lagoon, an isolation basin in Larsemann Hills (East Antarctica). The sediment core spans the last 6109 years and provides information on environmental changes in two different settings, i.e., (a) under the marine influence, and (b) as an isolated lake. Three cluster zones were identified viz., LZ1 (6109–2427 y BP: marine environment), LZ2 (2427–2101 y BP: transition zone) and LZ3 (2101–116 y BP: freshwater environment). Fine grain sediments (silt) are dominant in LZ1, indicating a strong hydrodynamic energy conditions affected by tidal currents with low organic matter. Higher sand content during the transition period (LZ2) indicates the strongest hydrodynamic condition and sediment deposition from sea ice. The increasing trend of OM (cyanobacterial benthic mat) beginning at ~ 2101 y BP suggests the isolation of the lake. The highest fine grained sediments (silt-clay) in LZ3 suggests lowered meltwater derived detritus in response to mild austral summer conditions during the Late Holocene.
AB - Holocene paleoenvironmental changes along the East Antarctic margin have been reconstructed using marine and lake sediment cores. Isolation basins in the coastal ice-free regions offer continuous sedimentary sequences to reconstruct marine-freshwater transitions and its environmental changes. In this study, we present the grain size (sand-silt-clay) and organic matter variations in a 51 cm radiocarbon-dated sediment core from Pup Lagoon, an isolation basin in Larsemann Hills (East Antarctica). The sediment core spans the last 6109 years and provides information on environmental changes in two different settings, i.e., (a) under the marine influence, and (b) as an isolated lake. Three cluster zones were identified viz., LZ1 (6109–2427 y BP: marine environment), LZ2 (2427–2101 y BP: transition zone) and LZ3 (2101–116 y BP: freshwater environment). Fine grain sediments (silt) are dominant in LZ1, indicating a strong hydrodynamic energy conditions affected by tidal currents with low organic matter. Higher sand content during the transition period (LZ2) indicates the strongest hydrodynamic condition and sediment deposition from sea ice. The increasing trend of OM (cyanobacterial benthic mat) beginning at ~ 2101 y BP suggests the isolation of the lake. The highest fine grained sediments (silt-clay) in LZ3 suggests lowered meltwater derived detritus in response to mild austral summer conditions during the Late Holocene.
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U2 - 10.1016/j.polar.2021.100729
DO - 10.1016/j.polar.2021.100729
M3 - Article
AN - SCOPUS:85111315165
SN - 1873-9652
VL - 30
JO - Polar Science
JF - Polar Science
M1 - 100729
ER -