300キロの東テネシー地震地帯の地震構造モデル
Science (New York, N.Y.)
|April 29, 1994
まとめ
テネシー州東部の10年間の地震モニタリングにより,微小地震活動の線形地帯が特定されました. このゾーンは,地殻ブロックの境界付近に集中する,重要な地震ストレスのエネルギー放出を示しています.
科学分野:
- 地球科学 地球科学 地球科学
- 地震学 地震学とは
- 地質物理学 地質物理学とは地質物理学です.
背景:
- 地域の地震ネットワークは,テネシー州東部の微小地震を10年間監視してきた.
- 地震活動パターンの理解は,地域構造的ストレスと地殻の動態の評価に不可欠です.
研究 の 目的:
- テネシー州東部の地震活動地帯を特定し,特徴づけること.
- 地域内の地震的なストレンスエネルギーの放出を分析する.
- 地震性の関係と地殻の構造を調査する.
主な方法:
- 地域地震ネットワークからの10年間のマイクロ地震データの分析.
- 地震ストレスのエネルギー放出の計算,地殻面積で正常化.
- 地震活動と地下層の地殻ブロックの地質学的データとの相関.
主要な成果:
- テネシー州東部で,はっきりと定義された,直線的な地震活動ゾーンが特定されました.
- このゾーンは,過去10年間でロッキー山脈の東に第2位の地震性ストレンスエネルギー放出量を示した (地域によって正常化).
- 地震性は,強いと弱い地下層の地殻ブロックの境界の近くに集中しています.
結論:
- 特定された地震地帯は,地板内構造的ストレスが顕著な領域を表しています.
- 地震性の濃度は,地殻ブロックの境界が導管やストレス濃縮体として作用することを示唆しています.
- これらの発見は,安定した大陸内部の地震性を駆動するメカニズムを理解するのに役立ちます.
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