月の核の地震検出

Renee C Weber¹, Pei-Ying Lin, Edward J Garnero

¹NASA Marshall Space Flight Center, 320 Sparkman Drive, Huntsville, AL 35805, USA. renee.c.weber@nasa.gov

Science (New York, N.Y.)

|January 8, 2011

まとめ

新しい地震分析は,月が固体内核と流体外核を持っていることを明らかにし,部分的に溶けた境界層と揮発性欠乏した内部を示唆しています. この深い月面の洞察は,月の内部構造の理解を深める.

科学分野:

* 惑星科学 (惑星科学)
* 地震学について
*月面地質学月面地質学

背景:

*衛星データとアポロ時代の地震分析にもかかわらず,月の深い内部についての理解は限られている.
*以前のアポロミッションからの地震データは,月の構造に関する基本的な,しかし不完全な洞察を提供しました.

研究の目的:

* アポロの月の地震画像を,高度な配列処理技術を用いて再分析する.
* 月の核を示す地震反射と変換を特定する.
*月の内部構成と構造のモデルを精錬する.

主な方法:

* 既存のアポロ月の地震図に配列処理方法の適用.
*月の核から発生する反射と変換を含む地震波の振る舞いの分析.
* 鉄合金相図と組み合わせた地震データの解釈.

主要な成果:

*月の核から反射され,変換された地震エネルギーの検出.
* 層状の核構造を支持する証拠:固体内核と流体外核.
* 核の上の部分的に溶けた境界層の特定.
*月球の核は,体積で約60%が液体であるとの推定.
* 核が6%未満の軽量合金元素を含んでいる可能性が高いと判断.

結論:

* 月は固体層と流体層からなる異なる核を持っています.
* コアの構成は,揮発性物質が少ない内部と一致し,軽い元素を最小限に含んでいます.
*この研究は,月の深い内部構造と組成の理解を大幅に前進させる.

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