Maren Walter, Andreas Türke, Alexander Diehl, Christopher R. German, Christian Mertens, Jonathan Mette, Patrick Monien, Simon Prause, Jürgen Sültenfuß, Wolfgang Bach, Vera Schlindwein, Antje Boetius
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引用次数: 0
Abstract
The Aurora vent field (82°53.83′N, 6°15.32′W) is located in the weakly stratified Arctic Ocean under perennial ice cover at the western edge of the ultraslow-spreading Gakkel Ridge, the slowest spreading mid-ocean ridge on Earth. Here, we report data on the dispersal of the proximal hydrothermal plume in this extreme environment. The hydrothermal plume is of unusual dimensions, with a small horizontal, but large vertical extent, which is caused by the hydrography of the Arctic Ocean. Water column parameters such as turbidity and redox potential show a highly variable but horizontally confined non-buoyant plume. Dissolved iron (dFe), manganese (dMn), δ3He, and methane (CH4) all show distinct enrichment in the hydrothermal plume relative to background deep-water, but relatively low peak concentrations due to the dilution over a vertical extent of over 500 m. Plume particle samples exhibit elevated Fe/Al ratios consistent with Fe-oxyhydroxide precipitation close to the vent, whereas particulate Mn/Al ratios do not reveal any complementary pMn enrichment in the proximal plume. The positive correlation between Fe/Al, and several other element/Al ratios (e.g., P, V, As) is consistent with scavenging of these elements onto Fe-hydroxide plume particles and removal into the underlying sediments. Surface sediment samples collected close to Aurora reveal highly elevated concentrations of hydrothermally sourced elements in the immediate vicinity of the vent-site. For example, proximal surface sediments contained up to 8,222 mg kg−1 Cu, whereas Cu concentrations in core tops a few kilometers away from the site were much lower (<50 mg kg−1).
期刊介绍:
Geochemistry, Geophysics, Geosystems (G3) publishes research papers on Earth and planetary processes with a focus on understanding the Earth as a system. Observational, experimental, and theoretical investigations of the solid Earth, hydrosphere, atmosphere, biosphere, and solar system at all spatial and temporal scales are welcome. Articles should be of broad interest, and interdisciplinary approaches are encouraged.
Areas of interest for this peer-reviewed journal include, but are not limited to:
The physics and chemistry of the Earth, including its structure, composition, physical properties, dynamics, and evolution
Principles and applications of geochemical proxies to studies of Earth history
The physical properties, composition, and temporal evolution of the Earth''s major reservoirs and the coupling between them
The dynamics of geochemical and biogeochemical cycles at all spatial and temporal scales
Physical and cosmochemical constraints on the composition, origin, and evolution of the Earth and other terrestrial planets
The chemistry and physics of solar system materials that are relevant to the formation, evolution, and current state of the Earth and the planets
Advances in modeling, observation, and experimentation that are of widespread interest in the geosciences.