DOI: 10.1007/s00531-015-1221-z
Scopus记录号: 2-s2.0-84937622388
论文题名: Detrital zircon geochronology of the Cretaceous succession from the Iberian Atlantic Margin: palaeogeographic implications
作者: Dinis P.A. ; Dinis J. ; Tassinari C. ; Carter A. ; Callapez P. ; Morais M.
刊名: International Journal of Earth Sciences
ISSN: 14373254
出版年: 2016
卷: 105, 期: 3 起始页码: 727
结束页码: 745
语种: 英语
英文关键词: Detrital zircon geochronology
; Lusitanian basin
; Pangea break-up
; Provenance
; Unconformity
Scopus关键词: Cretaceous
; geochronology
; paleogeography
; provenance
; sandstone
; unconformity
; uranium-lead dating
; zircon
; Atlantic Ocean
; Atlantic Ocean (North)
; Bay of Biscay
; Iberian Margin
; Lisboa [Portugal]
; Lusitanian Basin
; Portugal
英文摘要: Detrital zircon U–Pb data performed on eight Cretaceous sandstone samples (819 age isotopic results) from the Lusitanian basin (west Portugal) constrain the history of uplift and palaeodrainage of western Iberia following break-up of Pangaea and opening of the North Atlantic Ocean. We examined the links between shifts in provenance and known basinwide unconformities dated to the late Berriasian, Barremian, late Aptian and Cenomanian–Turonian. The detrital zircon record of sedimentary rocks with wider supplying areas is relatively homogenous, being characterized by a clear predominance of late Palaeozoic ages (c. 375–275 Ma) together with variable proportions of ages in the range c. 800–460 Ma. These two groups of ages are diagnostic of sources within the Variscan Iberian Massif. A few samples also reveal significant amounts of middle Palaeozoic (c. 420–385 Ma) and late Mesoproterozoic to early Neoproterozoic (c. 1.2–0.9 Ga) zircon, which are almost absent in the basement to the east of the Lusitanian basin, but are common in terranes with a Laurussia affinity found in NW Iberia and the conjugate margin (Newfoundland). The Barremian unconformity marks a sudden rise in the proportion of c. 375–275 Ma zircon ages accompanied by a decrease in the abundance of the c. 420–385 Ma and c. 1.2–0.9 Ga ages. This shift in the zircon signature, which is contemporaneous with the separation of the Galicia Bank from Flemish Cap, reflects increased denudation of Variscan crystalline rocks and a reduction in source material from NW Iberia and adjoining areas. The late Aptian unconformity, which represents the largest hiatus in the sedimentary record, is reflected by a shift in late Palaeozoic peak ages from c. 330–310 Ma (widespread in Iberia) to c. 310–290 Ma (more frequent in N Iberia). It is considered that this shift in the age spectra resulted from a westward migration of catchment areas following major uplift in northern Iberia and some transport southward from the Bay of Biscay under the influence of a well-established Atlantic circulation. © 2015, Springer-Verlag Berlin Heidelberg.
URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84937622388&doi=10.1007%2fs00531-015-1221-z&partnerID=40&md5=dce9ef552dbb937852abf0bb95ded23e
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/70178
Appears in Collections: 影响、适应和脆弱性 气候减缓与适应
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作者单位: IMAR - Marine and Environmental Research Centre, Department of Earth Sciences, University of Coimbra, Coimbra, Portugal; Instituto de Geociências, Universidade de São Paulo/CPGeo, São Paulo, Brazil; Department of Earth and Planetary Sciences Birkbeck, University of London, London, United Kingdom; Centre for Geophysics, University of Coimbra, Coimbra, Portugal
Recommended Citation:
Dinis P.A.,Dinis J.,Tassinari C.,et al. Detrital zircon geochronology of the Cretaceous succession from the Iberian Atlantic Margin: palaeogeographic implications[J]. International Journal of Earth Sciences,2016-01-01,105(3)