Tcas-1. View to northeast from Summit Chief Mountain [SKse]. The Miocene Snoqualmie batholith (of the Snoqualmie family, Tcas) exposed on Mount Hinman has thermally metamorphosed Lower Eocene Swauk Formation (early extensional sedimentary rocks, Tees), which forms resistant crags of Bears Breast Mountain, and the Silver Pass Volcanic Member (Teev), which forms Summit Chief in foreground. Oligocene volcanic rocks of the Ohanepecosh episode (Tcao) forming Mount Daniel have also been recrystallized by heat from the nearby batholith. Contact dashed where approximately located. View image with annotation
|