Uploaded December 2019 | Updated September 2026, 2 weeks ago
At AGU 2019, Jonathan Tucker will present his poster, "Connecting the deep Earth volatile cycles."
When is the presentation?
Friday, 13, 2019 | 8:00 - 12:20 | Moscone South Poster Hall
Abstract:
The distribution of volatiles between Earth’s interior and exterior is continually being influenced by plate tectonic cycling [1]. While there is abundant geochemical evidence that many volatile elements derived from the ocean/atmosphere are cycled into the convecting mantle and resampled in oceanic basalts the degree to which the different volatile species remain coupled throughout the entire convective cycle remains unclear, in part because of the lack of coherent data sets that include both noble gases and major volatiles. Here, we present such a data set for noble gases, H2O, CO2, and halogens from an otherwise normal section of the Mid-Atlantic Ridge. Part of this section has an unusually strong signature of recycled Ar and Xe, which spatially correlates with high H2O/Ce ratios, providing a possible link between cycling of water and noble gases. We further show that globally in mid-ocean ridge basalts, water concentrations and heavy noble gas compositions are correlated, suggesting that subducted volatiles play a role in the mantle Ar, Xe, and water composition. The association of high water contents with recycled noble gas signatures suggests that diverse volatiles travel together and preserve their subduction provenance throughout mantle circulation and their eventual outgassing at mid-ocean ridges. The observed link between recycled water and noble gases in the mantle has important consequences for the deep Earth volatile cycles. For example, given the measured Xe isotopic composition of the modern-day mantle, and the observed secular change in the Xe isotopic composition of the Archean atmosphere, significant Xe recycling into the mantle was initiated post-Archean [2,3]. The correlation between Ar, Xe and water then raises questions about how important the deep water cycle was during Earth's earliest history.
Videographer: Katy Cain
Music: "Hip Jazz" by bensound.com
At AGU 2019, Jonathan Tucker will present his poster, "Connecting the deep Earth volatile cycles."
When is the presentation?
Friday, 13, 2019 | 8:00 - 12:20 | Moscone South Poster Hall
Abstract:
The distribution of volatiles between Earth’s interior and exterior is continually being influenced by plate tectonic cycling [1]. While there is abundant geochemical evidence that many volatile elements derived from the ocean/atmosphere are cycled into the convecting mantle and resampled in oceanic basalts the degree to which the different volatile species remain coupled throughout the entire convective cycle remains unclear, in part because of the lack of coherent data sets that include both noble gases and major volatiles. Here, we present such a data set for noble gases, H2O, CO2, and halogens from an otherwise normal section of the Mid-Atlantic Ridge. Part of this section has an unusually strong signature of recycled Ar and Xe, which spatially correlates with high H2O/Ce ratios, providing a possible link between cycling of water and noble gases. We further show that globally in mid-ocean ridge basalts, water concentrations and heavy noble gas compositions are correlated, suggesting that subducted volatiles play a role in the mantle Ar, Xe, and water composition. The association of high water contents with recycled noble gas signatures suggests that diverse volatiles travel together and preserve their subduction provenance throughout mantle circulation and their eventual outgassing at mid-ocean ridges. The observed link between recycled water and noble gases in the mantle has important consequences for the deep Earth volatile cycles. For example, given the measured Xe isotopic composition of the modern-day mantle, and the observed secular change in the Xe isotopic composition of the Archean atmosphere, significant Xe recycling into the mantle was initiated post-Archean [2,3]. The correlation between Ar, Xe and water then raises questions about how important the deep water cycle was during Earth's earliest history.
Videographer: Katy Cain
Music: "Hip Jazz" by bensound.com
