Much of the Chirikov basin floor, which is carpeted with relict sand, has more heavy minerals than Norton Sound where modern fine-grained sediments dominate. In addition, the western section of the Chirikov basin is broadly divisible into two areas with relatively high concentrations of heavy minerals, separated by an area of low heavy-mineral content that trends approximately northwest-southeast. The northern areas seems to be richer in garnet (especially the pink type), epidote, and chloritoid. Staurolite, though present in small amounts, is consistently present in higher proportions in these sediments than in the sediments of the southern area. The northern sediments probably were derived either directly or indirectly from the metamorphic and other rocks of Seward Peni sula, whereas the provenance for the southern sediments is in the rocks of St. Lawrence Island. Compared with Chirikov basin, the heavy minerals of many of the deeper areas of Norton Sound consist of more ortho- and clinopyroxene and lesser amounts of garnet, and are relatively more rounded and suggest a Yukon River source. The Yukon River sediment apparently has encroached on areas of the extreme eastern section of the Chirikov basin. The heavy minerals of the sediments of shallower and nearshore areas of Norton Sound differ from those of the deeper areas and indicate derivation from nearby land sources.

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