Professional Paper 1747
Abstract
The Sentinel Hill Core Test 1 well penetrated an intertonguing sequence of (1) the marine Schrader Bluff Formation in the depth intervals 950–1,180 ft and 690–751 ft, which consists of shoreface and offshore deposits that accumulated along a storm-dominated, barred shoreline; and (2) the nonmarine Prince Creek Formation in the depth intervals 751–950 ft and surface to 690 ft, which consists of fluvial channel, crevasse splay, backswamp, and ash fall deposits. The strata range in age from early Campanian to early Maastrichtian. An erosional contact at a depth of 690 ft at the base of the upper unit of the Prince Creek Formation is interpreted as a major regional sequence boundary, and the overlying conglomeratic fluvial channel deposits are interpreted to have accumulated in a paleovalley. In its more proximal reaches along the Colville River, channels of this paleovalley cut down 75 ft into the lowermost Prince Creek Formation and the uppermost Schrader Bluff Formation. Farther offshore, the equivalent surface to the aforementioned paleovalley appears to be a subtle discontinuity between middle and lower Schrader Bluff Formation shelfal marine strata. Still farther offshore, the equivalent paleovalley surface is interpreted as a marine mass-wasting surface that locally cuts through the lowermost Schrader Bluff Formation and into the underlying Seabee Formation. |
Version 1.0 Posted February 2008 |
Flores, R.M., Stricker, G.D., Decker, P.L., and Myers, M.D., 2007, Sentinel Hill Core Test 1—facies descriptions and stratigraphic reinterpretations of the Prince Creek and Schrader Bluff Formations, North Slope, Alaska: U.S. Geological Survey Professional Paper 1747, 31 p.
Abstract
Introduction
Previous Lithostratigraphic Descriptions
Prince Creek Formation
Schrader Bluff Formation
New Biostratigraphic Age Constraints
Sequence Stratigraphy and Depositional Setting
Facies Descriptions and Interpretations
Prince Creek Facies
Descriptions
Coarser Grained Facies
Finer Grained Facies
Organic-Rich Facies
Interpretations
Schrader Bluff Facies
Descriptions
Coarser Grained Facies
Finer Grained Facies
Interpretations
Acknowledgments
Summary
References Cited