Cordilleran sedimentary foreland basin 

(Late Jurassic-early Tertiary) 

(U.S.A. Pacific Northwest and Canadian Cordillera, unit TJs)

Consists chiefly of westerly derived clastic wedges of sandstone, conglomerate, shale, coal, and minor 
volcaniclastic rocks of Jurassic, Early Cretaceous, mid-Cretaceous and Late Cretaceous to Paleocene age. 
Older parts of basin grade eastward into marine shale. Only older western parts of basin that 
stratigraphically overly and are structurally imbricated with Proterozoic to Jurassic cratonal margin rocks 
are depicted on map. Younger eastern parts of basin, that are deposited on thin Paleozoic to early Mesozoic 
strata overlying Early Proterozoic crystalline cratonic rocks, are not depicted on map but extend across 
much of the North American craton on the map. REFERENCE: Wheeler and McFeely, 1991