A 9,387-ft (2,816.1-m) section of Upper Cretaceous-Lower Tertiary strata is exposed along Sabbath Creek in the northern ANWR of northeastern Alaska and represents a regressive depositional sequence. The entire section is divided into four lithologic units (A-D), each characterized by distinct depositional assemblages. Unit A, at the base of the section, consists of several coarsening-upward sequences of alternating thick organic-rich siltstones and fine-grained litharenites, representing deposition in subaqueous to lower delta-plain environments. Unit B stratigraphically overlies unit A and is characterized by multiple, mutually erosive, fining-upward sequences of fine to coarse pebble litharenites typical of point-bar sequences in a meandering stream environment (lower t upper delta plain). Unit C consists of multiple, poorly developed fining-upward sequences of dominantly clast- and matrix-supported pebble conglomerate interpreted as braided stream deposits. At the top of the section, unit D is characterized by multiple fining- and a few coarsening-upward sequences of organic-rich shale with minor amounts of medium to coarse litharenite and pebble conglomerate representing meandering stream deposition.

The Sabbath Creek section is lithologically dissimilar to coeval units to the west. The Sagavanirktok Formation and Colville Group contain pyroclastic material and thick coal beds not seen in the Sabbath Creek section. Instead, this section is lithologically similar to the Moose Channel formation--a regressive, fluvial, deltaic sequence exposed in the MacKenzie delta area of northwestern Canada. Consequently, detailed interpretation of the Sabbath Creek section has important implications concerning the petroleum potential of the Arctic National Wildlife Refuge and offshore Beaufort Sea.

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