Английская Википедия:Hidalgo Formation
Шаблон:Short description Шаблон:Infobox rockunit
The Hidalgo Formation is a geologic formation of Maastrichtian age (latest Cretaceous)[1] in southwestern New Mexico.[2] It is of interest to geologists for the clues it preserves of the nature of Laramide deformation in the latest Cretaceous.[3]
Description
The formation is mostly basaltШаблон:Sfn or andesite[4] lava flows, but with some interbedded breccia and pyroclastic rock and, in some locations, up to Шаблон:Convert of limestone and shale. The formation rests unconformably on the Ringbone FormationШаблон:Sfn or Skunk Ranch Formation,Шаблон:Sfn and varies greatly in thickness, from Шаблон:Convert.Шаблон:Sfn Argon-argon dating gives a consistent age between 70.53 and 71.44 million years.[5] The formation is overlain by the Rubio Peak Formation.Шаблон:Sfn
The formation is interpreted as a volcanic center located inland of the southwest coast of the Ringbone depositional basinШаблон:Sfn that erupted during Laramide tectonic deformation that partitioned the basin.[6] It may correlate with the Salero Formation of southeastern Arizona.[7]
History of investigation
The formation was first named the Hidalgo Volcanics by Samuel G. Lasky in 1978 for outcroups found throughout Hidalgo County, New Mexico.Шаблон:Sfn
References
