Prolonged history of silicic peralkaline volcanism in the eastern Pacific Ocean
摘要
Socorro Island, Mexico, is an alkaline and peralkaline volcanic island located in the eastern Pacific Ocean on a mid-ocean ridge spreading center that was abandoned at 
3.5 Ma. Silicic peralkaline rocks comprise up to 80%of the surface of the island, rendering Socorro virtually unique in the Pacific Ocean. Precise, replicate ages of 21 peralkaline trachytes and rhyolites reveal a history of episodic volcanic activity from 540 to 370 ka that may have culminated with caldera formation; repose periods between these episodes may have had maximum duration of 30 kyr.
3.5 Ma. Silicic peralkaline rocks comprise up to 80%of the surface of the island, rendering Socorro virtually unique in the Pacific Ocean. Precise, replicate ages of 21 peralkaline trachytes and rhyolites reveal a history of episodic volcanic activity from 540 to 370 ka that may have culminated with caldera formation; repose periods between these episodes may have had maximum duration of 30 kyr.