Bernard L. Mamet J. Thomas Dutro Jr. Irvin L. Tailleur 1972 New collections of foraminifers and macrofossils from Nuka Ridge, the type area of the enigmatic Nuka Formation, demonstrate that the type Nuka Formation contains at least two, and probably several, thrust sheets instead of a single continuous stratigraphic sequence as originally described. application/pdf 10.3133/ofr72372 en U.S. Geological Survey Revised age and structural interpretations of the Nuka Formation at Nuka Ridge, northwestern Alaska reports