@article{12fc9b5592f44d40b7f624ade7d7e3f9,
title = "Neogene sedimentary record of the evolution of a translated strike-slip basin along the Denali fault system: Implications for timing of displacement, composite basin development, and regional tectonics of southern Alaska",
abstract = "Analysis of the late Miocene to Holocene McCallum sedimentary basin, located along the south side of the eastern Denali fault system, provides a better understanding of strike-slip basin evolution, timing of displacement on the Denali fault, and tectonics of the southern Alaska convergent margin. Analysis of the McCallum basin utilizing measured stratigraphic sections, lithofacies analyses, and 40Ar/39Ar tephra ages documented a 564-m-thick, two-member stratigraphy. Fine-grained, lacustrine-dominated environments characterized deposition of the lower member, and coarse-grained, stream-dominated alluvial-fan environments characterized deposition of the upper member. The 40Ar/39Ar dating of tephras indicated that the lower member was deposited from 6.1 to 5.0 Ma, and the upper member was deposited from 5.0 to 3.8 Ma. Our stratigraphic analysis of the McCallum basin illuminates the development of a composite strike-slip basin, with the deposition of the lower member occurring along a transtensional fault section, and deposition of the upper member occurring along a transpressional fault section. This change in depositional and tectonic settings is interpreted to reflect ~79-90 km of transport of the basin along the Denali fault system based on Pleistocene-Holocene slip rates. Previous studies of the timing of Cenozoic displacement on the Denali fault system utilizing sedimentary records emphasized a Paleogene component; our findings, however, also require a significant Neogene component. Neogene strike-slip displacement and basin development along the Denali fault system were broadly coeval with development of high topography and related clastic wedges across southern Alaska in response to flat slab subduction of the Yakutat microplate.",
author = "Allen, {Wai K.} and Ridgway, {Kenneth D.} and Benowitz, {J. A.} and Waldien, {T. S.} and Roeske, {S. M.} and Fitzgerald, {P. G.} and Gillis, {R. J.}",
note = "Funding Information: This research was supported by the National Science Foundation (EAR-1828737, Ridgway; EAR-1550034, Fitzgerald; and EAR-1434656, EAR-1550123, Benowitz). Allen received additional support from an Alaska Geological Society scholarship, a Geological Society of America research grant, the American Indian Science and Engineering Society, the Cearley Basin Analysis Fund, an ExxonMobil Geosciences scholarship, and graduate student research funds from the Department of Earth, Atmospheric, and Planetary Sciences at Purdue University. Allen also received support from the Sloan Indigenous Graduate Partnership Program at Purdue University. We benefited from discussions with Christopher Andronicos, Jeffrey Trop, Julie Elliott, Paul Layer, and Lucy Flesch. We also thank Basin Analysis team members: Mariah Romero, Lauren Colliver, Kim Davis, Cooper Fasulo, Tim Henderson, and Brandon Keough for constructive criticism during various stages of this research. Cooper Fasulo and Brandon Keough are thanked for assistance in field work. We appreciate the guidance from Arizona LaserChron Center staff scientists during U-Pb data acquisition. We thank Geosphere reviewers Peter Haeussler and Paul McCarthy, and Associate Editor Julie Dumoulin for helpful constructive comments that significantly improved the manuscript. Allen and Ridgway also thank Jeffrey Benowitz and Anna Liljedahl for lodging in Fairbanks and logistical support. Ridgway acknowledges the late Warren Nokleberg for first making him aware of the exposures along McCallum Creek. Funding Information: This research was supported by the National Science Foundation (EAR-1828737, Ridgway; EAR-1550034, Fitzgerald; and EAR-1434656, EAR-1550123, Benowitz). Allen received additional support from an Alaska Geological Society scholarship, a Geological Society of America research grant, the American Indian Science and Engineering Society, the Cearley Basin Analysis Fund, an Exxon-Mobil Geosciences scholarship, and graduate student research funds from the Department of Earth, Atmospheric, and Planetary Sciences at Purdue University. Allen also received support from the Sloan Indigenous Graduate Partnership Program at Purdue University. We benefited from discussions with Christopher Andronicos, Jeffrey Trop, Julie Elliott, Paul Layer, and Lucy Flesch. We also thank Basin Analysis team members: Mariah Romero, Lauren Colliver, Kim Davis, Cooper Fasulo, Tim Henderson, and Brandon Keough for constructive criticism during various stages of this research. Cooper Fasulo and Brandon Keough are thanked for assistance in field work. We appreciate the guidance from Arizona LaserChron Center staff scientists during U-Pb data acquisition. We thank Geosphere reviewers Peter Haeussler and Paul McCarthy, and Associate Editor Julie Dumoulin for helpful constructive comments that significantly improved the manuscript. Allen and Ridgway also thank Jeffrey Benowitz and Anna Liljedahl for lodging in Fairbanks and logistical support. Ridgway acknowledges the late Warren Nokleberg for first making him aware of the exposures along McCallum Creek. Publisher Copyright: {\textcopyright} 2022. The Authors. All Rights Reserved.",
year = "2022",
doi = "10.1130/GES02435.1",
language = "English (US)",
volume = "18",
pages = "585--615",
journal = "Geosphere",
issn = "1553-040X",
publisher = "Geological Society of America",
number = "2",
}