DOI: 10.1016/j.epsl.2020.116146
论文题名: Exhumation history of the north-central Shanxi Rift, North China, revealed by low-temperature thermochronology
作者: Clinkscales C. ; Kapp P. ; Wang H.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2020
卷: 536 语种: 英语
中文关键词: intracontinental rifting
; low-temperature thermochronology
; North China tectonics
英文关键词: Apatite
; Fission reactions
; Industrial heating
; Silicate minerals
; Zircon
; Apatite fission tracks
; Forward modeling
; Geothermal gradients
; intracontinental rifting
; Low temperatures
; North China
; Paleoproterozoic
; Thermochronology
; Temperature
英文摘要: We present new apatite U-Th-Sm/He (AHe; n = 51), apatite fission track data (AFT; n = 12), and zircon U-Th/He (ZHe; n = 8) data for two elevation transects in the north-central Shanxi Rift, North China. Low-temperature thermochronologic data combined with forward and inverse time-temperature history models reveal a Precambrian to Quaternary thermal history characterized by: (1) cooling to <∼50 °C during the Proterozoic, consistent with the development of a regional unconformity above Neoarchean–Paleoproterozoic cratonic basement rocks; (2) reheating to <∼180 °C due to sediment burial during the Paleozoic to Mesozoic; (3) cooling at a rate >3.5 °C/Ma during the Late Jurassic to earliest Cretaceous Yanshanian orogeny; (4) a possible ca. 120-90 Ma reheating event due to elevated geothermal gradients and/or local sediment burial; (5) Late Cretaceous (ca. 110-65 Ma) cooling contemporaneous with regional extension in eastern Asia and denudation of the paleo-Taihangshan highlands; and finally, (6) post ca. 10 Ma cooling associated with extension in the Shanxi Rift. AFT dates from the deepest exhumed structural positions of the sampled footwall blocks are mostly >65 Ma and AHe dates tend to be highly dispersed within samples. AFT inverse and AHe forward model results indicate that samples were at temperatures of <∼75 °C by ca. 70 Ma. Despite the early Cenozoic and older AFT and AHe dates, metamict zircon grains with high effective uranium (eU >∼750 ppm) yield young ZHe dates of ca. 13-9 Ma, consistent with Late Miocene exhumation. We argue for the onset of latest cooling by ca. 10 Ma based on these ZHe dates; however, the precise timing for the onset of rifting remains uncertain. The results further suggest that Late Miocene–Quaternary extension in the north-central Shanxi Rift is responsible for ≤∼2.5 km of exhumation, such that published Quaternary extension and fault throw rates are significantly (>100%) higher than long-term rates inferred from the thermochronologic data. © 2020 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/164924
Appears in Collections: 气候变化与战略
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作者单位: Department of Geosciences, University of Arizona, 1040 E 4 E 4th Street, Tucson, AZ 85721, United States; Key Laboratory of Continental Collision and Plateau Uplift, Institute of Tibetan Plateau Research, Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing, 100101, China
Recommended Citation:
Clinkscales C.,Kapp P.,Wang H.. Exhumation history of the north-central Shanxi Rift, North China, revealed by low-temperature thermochronology[J]. Earth and Planetary Science Letters,2020-01-01,536