The age of carbonatites, kimberlites and lamprophyres from southern West Greenland: recurrent alkaline magmatism during 2500 million years
The age of carbonatites, kimberlites and lamprophyres from southern West Greenland: recurrent alkaline magmatism during 2500 million years
复制标题
西格陵兰岛南部碳酸岩、金伯利岩和煌斑岩的年龄：25亿年来反复发生的碱性岩浆作用
DOI：
10.1016/0024-4937(83)90025-7
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
K. Secher
中科院分区：
文献类型：
--
作者：
L. Larsen;D. Rex;K. Secher
碱性岩石侵入前寒武纪基底在西格陵兰南部至少五个独立的事件。Tupertalik碳酸盐岩侵入体大约或早于26.5亿年侵位;它现在变质为麻粒岩相，但可通过其微量元素含量识别。拉马尔岩脉在约公元前被侵入。18亿年又一次在CA。1 200百万年在约6亿年Sarfartôq碳酸盐岩侵入体和广泛的金伯利岩岩脉位于Holsteiborg-Strømfjord地区。2.25 - 1.15亿年Qaqarssuk碳酸盐岩杂岩位于Sukkertoppen地区，Fishenasset和Ivigtut之间有许多层状岩和金伯利岩岩脉。所有这些事件都与加拿大和斯堪的纳维亚半岛同期的碱性活动相关，并证实了碳酸岩就位的周期性。中生代侵入岩与大陆裂解和北大西洋形成之前的裂谷作用有关。600百万年的始寒武纪套被认为是在类似的条件下形成的大陆分裂和土卫八海洋的形成。
Alkaline rocks were intruded into the Precambrian basement in southern West Greenland during at least five separate episodes. The Tupertalik carbonatite intrusion was emplaced around or before 2650 m.y.; it is now metamorphosed in granulite facies but is recognisable by its trace element content. Lamprophyre dykes were intruded at ca. 1800 m.y. and again at ca. 1200 m.y. At ca. 600 m.y. the Sarfartôq carbonatite intrusion and extensive kimberlite dykes were emplaced in the Holsteiborg-Strømfjord region. At 225-115 m.y. the Qaqarssuk carbonatite complex was emplaced in the Sukkertoppen region, and numerous lamprophyre and kimberlite dykes were emplaced between Fishenasset and Ivigtut. All these episodes are correlatable with contemporaneous alkaline activity in Canada and Scandinavia and substantiate the periodicity of carbonatite emplacement. The Mesozoic suite of intrusions is related to rifting prior to continental break-up and the formation of the North Atlantic Ocean. The Eocambrian suite of 600 m.y. is thought to have formed under similar conditions during continental break-up and the formation of the Iapetus ocean.