Records of mantle geodynamics and atmospheric escape in Archean quartz.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 41191770.
- Also identified by DOI 10.1126/sciadv.aea3380 and PMC identifier 12588296.
- Licence recorded as CC BY-NC.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Early planetary degassing and atmospheric escape are two major, yet unconstrained, processes that shaped early Earth. Modeling predicts that the atmospheric <sup>20</sup>Ne/<sup>22</sup>Ne ratio is sensitive to solar-Ne mantle degassing over geological time. Until the Great Oxidation Event, atmospheric escape progressively depletes the atmosphere in Xe, leaving an isotopic imprint. However, the quantity of xenon in the ancient atmosphere remains largely unknown. In this study, we analyzed noble gases in Archean hydrothermal quartz fluid inclusions and show that a modern atmospheric <sup>20</sup>Ne/<sup>22</sup>Ne ratio was almost reached 2.7 Ga ago, implying intense mantle degassing during the first 1.7 billion years of Earth's history, three orders of magnitude higher than today. Furthermore, we determine an Archean atmospheric Xe/Kr ratio, 2.3 times higher than today, consistent with models of Xe depletion over time through atmospheric escape.