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The Atacama Fault Zone (AFZ) is an expansive system of faults cutting across the Chilean Coastal Cordillera in Northern Chile between the Andean Mountain range and the Pacific Ocean. The fault system is North-South striking and runs for more than 1100 km North and up to 50 km in width through the Andean Forearc Basin. The zone is a direct result of the ongoing subduction of the Eastward moving Nazca plate beneath the South American plate and is believed to have formed in the Early Jurassic during the beginnings of the Andean orogeny. The zone can be split into 3 regions: the North, Central and South. ==Tectonic history and formation== The AFZ has gone through periods of inactivity and reactivation since its inception in the Cretaceous. The fault series was formed through a complex series of tectonic regimes dating back to the Early Jurassic. # The Andean back-arc basin separates from the Pacific Ocean in the Early Jurassic.〔 # Intra-arc ductile deformation occurs, creating North-striking mylonitic shear zones in the late Jurassic.〔 # Belt formed through a compressive regime in the early Cretaceous.〔 # Compression of the Andean basement in the mid-Cretaceous.〔 # Regime of extension from the Oligocene to Miocene.〔 # Large brittle reactivations from the Miocene to Present.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Atacama Fault」の詳細全文を読む スポンサード リンク
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