大気化学と火星の深層硫黄循環の間の同位体リンク
Heather B Franz1, Sang-Tae Kim2, James Farquhar3
11] Center for Research and Exploration in Space Science and Technology, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA [2] Department of Geology and Earth System Science Interdisciplinary Center, University of Maryland, College Park, Maryland 20742, USA.
Nature
|April 18, 2014
まとめ
火星の隕石は,火星の歴史を通して,硫黄がマグマに吸収されることが一般的であったことを明らかにしています. この過程は,硫黄同位体シグネチャーによって証明され,地球と比較して火星の独特な大気化学を強調しています.
科学分野:
- 惑星科学は惑星科学である.
- 地質化学 地質化学
- イソトープ地球化学 イソトープ地球化学
背景:
- 火星の隕石は,惑星の地質学的および大気学的過程についての洞察を提供します.
- 地殻物質のマグマ吸収を理解することは,地化学的サインの解釈に不可欠です.
- 濃縮されたシェルゴッタイトにおける軽い希土元素の起源は議論されている (地殻の同化対マントルの混合).
研究 の 目的:
- 火星隕石の硫黄同位体体系論を調査し,地殻の同化を理解する.
- 火星のマグマにおける硫黄の吸収の範囲とタイミングを決定する.
- 火星の大気中の硫黄の化学成分と地球の化学成分を比較するために.
主な方法:
- 40個の火星の隕石の硫黄の同位体分析は,シェルゴッタイト,ナクリト,アランヒルズ84001およびチャッシーニを含む.
- 硫黄の同位体シグネチャーのための火性硫化物と硫酸の分析.
主要な成果:
- 地質史を通じて火星のマグマに硫黄が広く吸収されたという強力な証拠がある.
- 質量独立分離 (MIF) を示す硫黄の同位体シグネチャーが観察されました.
- MIFのシグネチャーは,マグマの上昇と配置の間に硫黄の同化を示唆しています.
- 火星の大気中の硫黄の処理は,隕石に保存され,地球のと異なるシグネチャーを示しています.
結論:
- 火星のマグマによる硫黄の吸収は,惑星の歴史を通して広範囲にわたるプロセスでした.
- 観測されたMIFシグネチャーは,地殻の同化および置換過程の証拠を提供します.
- 地球の大気と火星の大気間の支配的な硫黄化学には根本的な違いがあります.
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