| Summary: | Dissertation (Ph.D.) University of Alaska Fairbanks, 2018 Structural and stratigraphic interpretation of 2D multi-channel seismic (MCS) reflection profiles through recognition of the sub-surface reflection patterns and integration of the seismic interpretation with the other geophysical and geological data reveal the history of the Chukchi Borderland. This investigation provides new constraints for the tectonic development of the Amerasia Basin. North-striking normal faults of the Chukchi Borderland dissect the continental basement into the Chukchi Plateau, Northwind Basin and Northwind Ridge from west to east. A well-developed angular unconformity (Au) separates the stratigraphic section into sub and super-Au seismic units. Sub-Au units include: (1) seaward dipping reflections (SDRs) observed in the juncture between the North Chukchi-Toll Basins and Chukchi Plateau; (2) growth and folded strata in the Northwind Basin; (3) thrust faults in the Northwind Basin and over the Northwind Ridge; and (4) a clinoform sequence that downlaps onto the extended continental crust of the Canada Basin, supported by presence of SDRs and diapiric reflections within the crust. Au is inferred to correlate to the Hauterivian (LCu) and the Middle Jurassic (Ju) unconformities of the Alaska North Slope. The SDRs indicate that the southwestern margin of the Chukchi Borderland may be a rifted continental margin. Loosely constrained age control of a super-Au unit (inferred condensed section, perhaps correlative to Hauterivian pebble shale or the Jurassic upper Kingak shale units of Alaska North Slope) implies that the rifted margin subsided no later than the earliest Cretaceous, providing a plausible time constraint for Middle Jurassic-earliest Cretaceous rifting in the North Chukchi Basin. The growth strata and north-striking normal faults of the Northwind Basin are continuous with the extensional structures of the Mississippian Hanna Trough, providing a geologic linkage between the two. The folding and thrust faults reveal a phase of ...
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