Lead isotopic signatures in Antarctic marine sediment cores: A comparison between 1M HCl partial extraction and HF total digestion pre-treatments for discerning anthropogenic inputs

Abstract. Antarctic palaeoclimate evolution and vegetation history after the formation of a continent-scale cryosphere at the Eocene–Oligocene boundary, 33.9 million years ago, has remained a matter of controversy. In particular, the reconstruction of terrestrial climate and vegetation has been strongly hampered by uncertainties in unambiguously identifying non-reworked as opposed to reworked sporomorphs that have been transported into Antarctic marine sedimentary records by waxing and waning ice sheets. Whereas reworked sporomorph grains over longer non-successive geological timescales are easily identifiable within younger sporomorph assemblages (e.g. Permian sporomorphs in Pliocene sediments), distinguishing non-reworked from reworked material in palynological assemblages over successive geological time periods (e.g. Eocene sporomorphs in Oligocene sediments) has remained problematic. This study presents a new quantitative approach to identifying non-reworked pollen assemblages in marine sediment cores from circum-Antarctic waters. We measured the fluorescence colour signature, including red, green, and blue fluorescence; brightness; intensity; and saturation values of selected pollen and spore taxa from Eocene, Oligocene, and Miocene sediments from the Wilkes Land margin Site U1356 (East Antarctica) recovered during Integrated Ocean Drilling Program (IODP) Expedition 318. Our study identified statistically significant differences in red-fluorescence values of non-reworked sporomorph taxa against age. We conclude that red fluorescence is a reliable parameter for identifying the presence of non-reworked pollen and spores in Antarctic marine sediment records from the circum-Antarctic realm that are influenced by glaciation and extensive reworking. Our study provides a new tool to accurately reconstruct Cenozoic terrestrial climate change on Antarctica using fossil pollen and spores.

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Environmental DNA preserved in marine sediment for detecting jellyfish blooms after a tsunami

Scientific Reports ◽

10.1038/s41598-021-94286-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Mizuki Ogata ◽

Reiji Masuda ◽

Hiroya Harino ◽

Masayuki K. Sakata ◽

Makoto Hatakeyama ◽

...

Keyword(s):

Marine Sediment ◽

Oil Spills ◽

Sediment Cores ◽

Environmental Dna ◽

Target Species ◽

Tank Experiment ◽

Polycyclic Aromatic ◽

Flow Through ◽

High Concentrations ◽

One Year

AbstractEnvironmental DNA (eDNA) can be a powerful tool for detecting the distribution and abundance of target species. This study aimed to test the longevity of eDNA in marine sediment through a tank experiment and to use this information to reconstruct past faunal occurrence. In the tank experiment, juvenile jack mackerel (Trachurus japonicus) were kept in flow-through tanks with marine sediment for two weeks. Water and sediment samples from the tanks were collected after the removal of fish. In the field trial, sediment cores were collected in Moune Bay, northeast Japan, where unusual blooms of jellyfish (Aurelia sp.) occurred after a tsunami. The samples were analyzed by layers to detect the eDNA of jellyfish. The tank experiment revealed that after fish were removed, eDNA was not present in the water the next day, or subsequently, whereas eDNA was detectable in the sediment for 12 months. In the sediment core samples, jellyfish eDNA was detected at high concentrations above the layer with the highest content of polycyclic aromatic hydrocarbons, reflecting tsunami-induced oil spills. Thus, marine sediment eDNA preserves a record of target species for at least one year and can be used to reconstruct past faunal occurrence.

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Mercury pollution in marine sediment cores near cinnabar deposits and a chlor-alkali plant

The Science of The Total Environment ◽

10.1016/0048-9697(86)90016-1 ◽

1986 ◽

Vol 57 ◽

pp. 111-120 ◽

Cited By ~ 14

Author(s):

Franco Baldi ◽

Maria L. D'Amato

Keyword(s):

Marine Sediment ◽

Sediment Cores ◽

Mercury Pollution

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A 2400 yr record of natural events and anthropogenic impacts in intercorrelated terrestrial and marine sediment cores: Waipaoa sedimentary system, New Zealand

Geological Society of America Bulletin ◽

10.1130/b25996.1 ◽

2007 ◽

Vol 119 (11-12) ◽

pp. 1415-1432 ◽

Cited By ~ 42

Author(s):

B. Gomez ◽

L. Carter ◽

N. A. Trustrum

Keyword(s):

New Zealand ◽

Marine Sediment ◽

Anthropogenic Impacts ◽

Sediment Cores ◽

Sedimentary System

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The Search for Supernova-Produced Radionuclides in Terrestrial Deep-Sea Archives

Publications of the Astronomical Society of Australia ◽

10.1071/as11070 ◽

2012 ◽

Vol 29 (2) ◽

pp. 109-114 ◽

Cited By ~ 14

Author(s):

J. Feige ◽

A. Wallner ◽

S. R. Winkler ◽

S. Merchel ◽

L. K. Fifield ◽

...

Keyword(s):

Solar System ◽

Marine Sediment ◽

Deep Sea ◽

Massive Stars ◽

Sediment Cores ◽

Deep Ocean ◽

Transport Mechanisms ◽

Supernova Shell ◽

Process Element ◽

Insight Into

AbstractAn enhanced concentration of 60Fe was found in a deep ocean crust in 2004 in a layer corresponding to an age of ∼2 Myr. The confirmation of this signal in terrestrial archives as supernova-induced and the detection of other supernova-produced radionuclides is of great interest. We have identified two suitable marine sediment cores from the South Australian Basin and estimated the intensity of a possible signal of the supernova-produced radionuclides 26Al, 53Mn, 60Fe, and the pure r-process element 244Pu in these cores. The finding of these radionuclides in a sediment core might allow us to improve the time resolution of the signal and thus to link the signal to a supernova event in the solar vicinity ∼2 Myr ago. Furthermore, it gives us an insight into nucleosynthesis scenarios in massive stars, condensation into dust grains and transport mechanisms from the supernova shell into the solar system.

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