Arctic Alaska is a ＇suspect＇ terrane that encompasses approximately 20%of Alaska,stretching from the southern Brooks Range all the way to the continental shelves of the Chukchi and Beaufort Seas.Although the origin ...Arctic Alaska is a ＇suspect＇ terrane that encompasses approximately 20%of Alaska,stretching from the southern Brooks Range all the way to the continental shelves of the Chukchi and Beaufort Seas.Although the origin and subsequent travels of this large crustal fragment are debated among geologists,most researchers agree upon its composite nature and exotic origin.To constrain the early geological history of this terrane,we describe a recent expedition to the Doonerak fenster of the central Brooks Range.This area has long been regarded as a key locality for understanding the structural evolution of the Mesozoic-Cenozoic Brooks Range orogen;however,our target was different：a unique sequence of volcanic and siliciclastic rocks（Apoon assemblage） exposed beneath a profound pre-Mississippian unconformity,which we argue is of key importance to understanding the early Paleozoic tectonic history of northern Alaska and the greater Arctic.展开更多
基金supported by a Geological Society of America graduate student research grant,Harvard University,Dartmouth Collegea National Science Foundation(NSF) Tectonics grant (EAR-1624131)+1 种基金supported by a Stanford McGee Grantand a NSF Graduate Research Fellowshipsupported by Harvard University
文摘Arctic Alaska is a ＇suspect＇ terrane that encompasses approximately 20%of Alaska,stretching from the southern Brooks Range all the way to the continental shelves of the Chukchi and Beaufort Seas.Although the origin and subsequent travels of this large crustal fragment are debated among geologists,most researchers agree upon its composite nature and exotic origin.To constrain the early geological history of this terrane,we describe a recent expedition to the Doonerak fenster of the central Brooks Range.This area has long been regarded as a key locality for understanding the structural evolution of the Mesozoic-Cenozoic Brooks Range orogen;however,our target was different：a unique sequence of volcanic and siliciclastic rocks（Apoon assemblage） exposed beneath a profound pre-Mississippian unconformity,which we argue is of key importance to understanding the early Paleozoic tectonic history of northern Alaska and the greater Arctic.
