학술논문

Large-scale, crustal-block vertical extrusion between the Hines Creek and Denali Faults coeval with slip localization on the Denali Fault since ca. 45 Ma, Hayes Range, Alaska, USA
Document Type
Academic Journal
Source
Geosphere (Boulder, CO). 18(3):1030-1054
Subject
16|Structural geology
03|Geochronology
(U-Th)/He
absolute age
Alaska
Alaska Range suture zone
apatite
Ar/Ar
biotite
Border Ranges Fault
Cenozoic
computer programs
data processing
deformation
Denali Fault
Eocene
Fairweather Fault
faults
fission-track dating
geochronology
Hayes Range
HeFTy model
Hines Creek Fault
magmatism
mica group
Miocene
Neogene
nesosilicates
North America
numerical models
Oligocene
orthosilicates
Paleogene
phosphates
sheet silicates
silicates
strike-slip faults
suture zones
tectonics
Tertiary
U/Pb
United States
Yakutat Terrane
zircon
zircon group
Language
English
ISSN
1553-040X
Abstract
Oblique convergence along strike-slip faults can lead to both distributed and localized deformation. How focused transpressive deformation is both localized and maintained along sub-vertical wrench structures to create high topography and deep exhumation warrants further investigation. The high peak region of the Hayes Range, central Alaska, USA, is bound by two lithospheric scale vertical faults: the Denali fault to the south and Hines Creek fault to the north. The high topography area has peaks over 4000 m and locally has experienced more than 14 km of Neogene exhumation, yet the mountain range is located on the convex side of the Denali fault Mount Hayes restraining bend, where slip partitioning alone cannot account for this zone of extreme exhumation. Through the application of U-Pb zircon, 40Ar/39Ar (hornblende, muscovite, biotite, and K-feldspar), apatite fission-track, and (U-Th)/He geo-thermochronology, we test whether these two parallel, reactivated suture zone structures are working in tandem to vertically extrude the Between the Hines Creek and Denali faults block on the convex side of the Mount Hayes restraining bend. We document that since at least 45 Ma, the Denali fault has been bent and localized in a narrow fault zone (