Zircon U-Pb ages from the Galway granite and the Dalradian, Connemara, Ireland
Zircon U-Pb ages from the Galway granite and the Dalradian, Connemara, Ireland
复制标题
爱尔兰康尼马拉戈尔韦花岗岩和达尔拉迪安花岗岩的锆石 U-Pb 年龄
DOI：
10.1144/sjg05040375
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发表时间：
1969
影响因子：
0.7
通讯作者：
R. Pidgeon
中科院分区：
文献类型：
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作者：
R. Pidgeon
锆石U-Pb年龄为510±10百万年。Cashel-Lough Wheelaun基性侵入体的形成在Connemara的Dalradian变质作用的时间跨度早期建立了一个点;侵入体在F1之后，M1晚期，但在F2之前。这也是Lower Llanvirn基底的最大年龄，如果使用5.0 × 1010年Rb 87半衰期，则可以与Rb-Sr结果联系起来。变质沉积岩锆石的结果与400 - 510百万年之间的同位素扰动一致。并表明大部分烃源岩的年龄超过1200百万年。变质沉积锆石的U-Pb同位素关系与同生锆石系列具有相似的特征。
Synopsis The zircon U-Pb age of 510±10 m.y. of the Cashel-Lough Wheelaun basic intrusion establishes a point early in the time span of the Dalradian metamorphism in Connemara; the intrusion is post F1 and late M1 but pre-F2. This is also a maximum age for the base of the Lower Llanvirn and can be linked with Rb-Sr results if the 5.0 × 1010y Rb87 half-life is used. The metasedimentary zircon results are compatible with an isotopic disturbance(s) between 400 and 510 m.y. and suggest that a large proportion of the source rocks were older than 1200 m.y. The U-Pb isotopic relationships of the metasedimentary zircons have similar features to those of cogenetic zircon suites.