ニューマドリッドの地震地帯では,急速なプラーク内ストレスの蓄積が起きている
Science (New York, N.Y.)
|September 18, 1992
まとめ
ニューマドリードの地震地帯で検出された地殻の急速なストレンの蓄積は,将来のプラーク内地震の危険性が高まっていることを示唆しています. この発見は,地震が活発な地域における地震リスクの評価において極めて重要です.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 地震学 地震学とは
- ジオデシ (Geodesy) とは
背景:
- ニューマドリッド地震地域 (NMSZ) は,歴史上重要な地震活動で知られており,1811年から1812年にかけての3つの大きな地震も含まれています.
- 内部プレート内地震地帯は,まれに発生する大規模な現象のために,危険性評価にユニークな課題を提示します.
研究 の 目的:
- 南部NMSZにおける現在の地殻の菌株の蓄積を評価する.
- この地域における将来の有害なプレート内地震の可能性を評価する.
主な方法:
- グローバルポジショニングシステム (GPS) を使用した歴史的な三角測量ネットワークの再測定.
- 地表層の変形パターンを検出するために,地検データの分析.
主要な成果:
- 1950年代以降,顕著で急速な地殻の菌株の蓄積が観察されています.
- 観測されたストレンは,北東方向の断層に沿った右側ストライクスリップ運動と一致しています.
- 現在の地震性パターンは,推論された断層方向と一致しています.
結論:
- 地殻のストレスの検出は,将来の板内地震のリスクのある地域を特定するための貴重なツールです.
- NMSZは,最近の大規模な歴史的な地震がなくても,潜在的な地震の危険性を示す進行中の変形を示しています.
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