The Geology, Sedimentology, And Stratigraphy Of The Ordovician Through Silurian Smith Formation, Northern Seward Peninsula, Alaska

Abstract

The purpose of this study is to determine the stratigraphic relationships and depositional settings of three outcrops at Cape Deceit, northern Seward Peninsula, Alaska. These rocks are lower Paleozoic limestone, dolostone, and shale. They have CAI values that indicate greenschist facies metamorphism. They have retained most of their primary sedimentary fabric, although they are juxtaposed with multiply deformed calc-silicate schists. The sedimentary rocks were deposited as a prograding base-of-slope apron. Environments recognized include distal basin, outer apron and inner apron. Ordovician graptolites and Ordovician through Silurian conodonts occur in these outcrops. Chronostratigraphic and environmental relationships suggest there is a genetic relationship between these three individual outcrops and that, when combined, they form a composite stratigraphic section named the Smith Formation. The Smith Formation is correlative in age with carbonate rocks of the York Mountains and western Brooks Range. <p>