Rapid fortmation of the Small Isles Tertiary centre constrained by precise 40Ar/39Ar and U-Pb ages

被引:49
作者
Chambers, LM [1 ]
Pringle, MS
Parrish, RR
机构
[1] NERC, Isotope Geosci Lab, Kingsley Dunham Ctr, Keyworth NG12 5GG, Notts, England
[2] Univ Edinburgh, Dept Geol & Geophys, Edinburgh EH9 3JW, Midlothian, Scotland
[3] Scottish Univ, Environm Res Ctr, Glasgow G75 0QF, Lanark, Scotland
[4] Univ Leicester, Dept Geol, Leicester LE1 7RH, Leics, England
基金
英国自然环境研究理事会;
关键词
40Ar/39Ar; U-Pb; BTIP; NAIP; Iceland plume;
D O I
10.1016/j.lithos.2004.09.008
中图分类号
P3 [地球物理学]; P59 [地球化学];
学科分类号
0708 [地球物理学]; 070902 [地球化学];
摘要
The relative chronology of magmatic and tectonic events is key to an understanding of the influence of the Iceland plume on the North Atlantic. In particular, the location and duration of magmatism is of fundamental importance. Initial widespread flood basalt formation occurred in Baffin Island, Greenland, and Britain before complete plate break up at 56 Ma after which time magmatism became concentrated in the active rift zone. Historically the British Tertiary Igneous Province (BTIP) has been instrumental in advancing many concepts of igneous petrology. However, the absolute age and duration of the province remains unresolved. Here, we present new internally consistent 40Ar/39Ar ages that help to constrain the volcanic activity in the Small Isles centre to within 2 my. This short duration has implications for the onset of magmatism, in the larger North Atlantic province, the rapid unroofing of the Rum volcano, and more significantly, some of the evidence used to propose pulsing of the Iceland plume. (C) 2004 Elsevier B.V. All rights reserved. The relative chronology of magmatic and tectonic events is key to an understanding of the influence of the Iceland plume on the North Atlantic. In particular, the location and duration of magmatism is of fundamental importance. Initial widespread flood basalt formation occurred in Baffin Island, Greenland, and Britain before complete plate break up at 56 Ma after which time magmatism became concentrated in the active rift zone. Historically the British Tertiary Igneous Province (BTIP) has been instrumental in advancing many concepts of igneous petrology. However, the absolute age and duration of the province remains unresolved. Here, we present new internally consistent 40Ar/39Ar ages that help to constrain the volcanic activity in the Small Isles centre to within 2 my. This short duration has implications for the onset of magmatism, in the larger North Atlantic province, the rapid unroofing of the Rum volcano, and more significantly, some of the evidence used to propose pulsing of the Iceland plume. (C) 2004 Elsevier B.V. All rights reserved. The relative chronology of magmatic and tectonic events is key to an understanding of the influence of the Iceland plume on the North Atlantic. In particular, the location and duration of magmatism is of fundamental importance. Initial widespread flood basalt formation occurred in Baffin Island, Greenland, and Britain before complete plate break up at 56 Ma after which time magmatism became concentrated in the active rift zone. Historically the British Tertiary Igneous Province (BTIP) has been instrumental in advancing many concepts of igneous petrology. However, the absolute age and duration of the province remains unresolved. Here, we present new internally consistent 40Ar/39Ar ages that help to constrain the volcanic activity in the Small Isles centre to within 2 my. This short duration has implications for the onset of magmatism, in the larger North Atlantic province, the rapid unroofing of the Rum volcano, and more significantly, some of the evidence used to propose pulsing of the Iceland plume. (C) 2004 Elsevier B.V. All rights reserved.
引用
收藏
页码:367 / 384
页数:18
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