Late Jurassic syn-rift deposition in the Flemish Pass basin, offshore Newfoundland: Evidence for Tithonian magmatism and Appalachian-Variscan sediment sources from quantitative mineral and detrital zircon U-Pb-Hf isotope studies of Mizzen discovery strata

被引：4

作者：

Beranek, Luke P. ^{[1
]}

Nissen, Adam ^{[1
]}

Murphy, Sandra ^{[1
]}

Grant, David ^{[2
]}

Goudie, Dylan ^{[2
]}

Oldham, Lindsay ^{[1
]}

Johns-Buss, Emily G. ^{[1
]}

机构：

[1] Mem Univ Newfoundland, Dept Earth Sci, 9 Arctic Ave, St John, NF A1B 3X5, Canada

[2] Mem Univ Newfoundland, Core Res Equipment & Instrument Training Network, St John, NF A1C 5S7, Canada

来源：

MARINE AND PETROLEUM GEOLOGY | 2022年 / 146卷

基金：

加拿大自然科学与工程研究理事会;

关键词：

Detrital zircon; Provenance; Magma-poor rift; Grand banks; Flemish pass basin; Newfoundland; Quantitative mineralogy;

D O I：

10.1016/j.marpetgeo.2022.105960

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

Quantitative mineral and detrital zircon U-Pb-Hf isotope studies of syn-rift sandstone units in the Mizzen F-09 delineation well, northern Flemish Pass basin, were conducted to test competing models for Grand Banks paleogeography and Late Jurassic development of the Newfoundland-Iberia magma-poor rift system. Bodhran formation (informal nomenclature) strata yield ca. 145-155 Ma detrital zircon grain populations that indicate a late Tithonian (146 +/- 1 Ma) maximum depositional age for syn-rift fluvial to tide-modulated fluvial strata in Mizzen F-09 and evidence for Grand Banks rift magmatism to have occurred throughout the Late Jurassic. Late Tithonian tectonic subsidence and magmatism in the northern Flemish Pass basin region were coincident with the onset of necking processes and extreme crustal thinning within the Newfoundland-Iberia rift system. The chondritic to superchondritic Hf isotope compositions of Late Jurassic detrital zircon grains indicate repeated partial melting of lithospheric mantle during rift development, perhaps along master detachment faults or transfer zone systems. Bodhran formation strata have chemically unstable minerals (plagioclase, potassium feldspar, garnet, muscovite, rutile, staurolite) and late Paleozoic to Paleoarchean detrital zircon age populations that together show provenance from Appalachian-Variscan basement and cover assemblages. A positive correlation between the abundance of metamorphic minerals and unique-aged, mid-Permian (ca. 271-280 Ma) detrital zircon grains from post-Variscan igneous rocks indicate Iberian provenance contributions to Bodhran formation strata. The new results from Mizzen F-09 are consistent with models for WNW-directed fluvial discharge into the northern Flemish Pass basin and sediment derivation from upper Paleozoic foreland basin or cover assemblages located west of Variscan front, some which may have been stripped off Beothuk Knoll, Flemish Cap, or adjacent highlands.

引用

页数：16