气候变化领域集成服务门户(CCPortal): Thermo-kinematic modeling of detachment-dominated extension, northeastern Death Valley area, USA: Implications for mid-crustal thermal-rheological evolution

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DOI	10.1016/j.tecto.2021.228755
	Thermo-kinematic modeling of detachment-dominated extension, northeastern Death Valley area, USA: Implications for mid-crustal thermal-rheological evolution
	Lutz B.; Ketcham R.A.; Axen G.J.; Beyene M.A.; Wells M.L.; van Wijk J.W.; Stockli D.F.; Ross J.I.
发表日期	2021
ISSN	00401951
卷号	808
英文摘要	The deep structure of continental detachment faults remains debated. Thermo-mechanical models generate detachments that either transect the lithosphere or become distributed shear zones in the mid-lower crust, depending on prescribed thermo-rheological conditions. However, these geometries and prescribed conditions remain little constrained by geology-based reconstructions. We present stepwise, balanced reconstructions of a 160 km-long cross-section through two detachment faults in the southwest USA. Reconstructions form the basis of iteratively improved 2D forward thermo-kinematic numerical simulations of detachment fault slip, footwall exhumation, heat advection, and footwall zircon (U-Th)/He cooling ages. Thermo-kinematic model solutions are calibrated iteratively against surface heat flow, pre- and post-extensional geotherms, inferred Moho temperatures, and thermochronometric data from one detachment footwall. Best-fit models predict the thermal and geometric evolution of the crust and detachments, respectively, during extension. The detachment initially rooted into a mid-crustal shear zone (~7.5–12 km depth) and was probably delocalized in the deep middle crust (>12–15 km). The maximum principal stress was likely non-vertical in the middle crust at detachment initiation, possibly due to mantle upwelling. Our reconstructions suggest that the upper crust and lower crust-mantle lithosphere were decoupled by a weak, mid-crustal layer during early detachment faulting. The weak layer was thinned, cooled, partially embrittled, and therefore strengthened by continued detachment slip. This increased lithospheric mechanical coupling and caused the locus of upper-crustal extension to shift. Thinning of a weak mid-crustal layer, as is thought to precede coupled hyperextension and mantle exhumation during rifting, was mostly complete in our study area by ~7–6 Ma. © 2021 Elsevier B.V.
关键词	Cordilleran thrust belt Detachment Metamorphic core complex Mid-crustal flow Thermo-kinematic model
英文关键词	Fault slips; Iterative methods; Silicate minerals; Structural geology; Zircon; Crustal extension; Detachment faulting; Mantle upwellings; Maximum principal stress; Mechanical coupling; Rheological evolution; Surface heat flow; Thermomechanical model; Kinematics; computer simulation; crustal structure; detachment fault; extensional tectonics; fault slip; modeling; rheology; rifting; stress; California; Death Valley; United States
语种	英语
来源期刊	Tectonophysics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/208022
作者单位	Earth and Environmental Science, New Mexico Institute of Mining and Technology, 801 Leroy Place, Socorro, NM 87801, United States; Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin, Austin, TX 78712, United States; Department of Geoscience, University of Nevada Las Vegas, Las Vegas, NV 89154, United States; Turner Fairbank Highway Research Center, Federal Highway Administration, McLean, VA 22101, United States; New Mexico Bureau of Geology and Mineral Resources, 801 Leroy Place, Socorro, NM 87801, United States
推荐引用方式 GB/T 7714	Lutz B.,Ketcham R.A.,Axen G.J.,et al. Thermo-kinematic modeling of detachment-dominated extension, northeastern Death Valley area, USA: Implications for mid-crustal thermal-rheological evolution[J],2021,808.
APA	Lutz B..,Ketcham R.A..,Axen G.J..,Beyene M.A..,Wells M.L..,...&Ross J.I..(2021).Thermo-kinematic modeling of detachment-dominated extension, northeastern Death Valley area, USA: Implications for mid-crustal thermal-rheological evolution.Tectonophysics,808.
MLA	Lutz B.,et al."Thermo-kinematic modeling of detachment-dominated extension, northeastern Death Valley area, USA: Implications for mid-crustal thermal-rheological evolution".Tectonophysics 808(2021).