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纽芬兰白湾(White Bay)区Coney Head杂岩由奥陶纪泰康造山运动期间侵位于大陆边缘之上的异地深成岩和变形了的与其相当的岩石构成,据认为是在一岛弧中由部分熔融而形成的英闪岩的锆石年龄为472±2Ma,这表明这里的英闪岩是在阿列尼格(Arenig)期结晶的.有一种U/Pb(锆石+金红石)年龄勾433±2Ma的微花岗昔切割了英闪岩.微花岗岩中残留的元古代锆石表明,岩浆岩有一部分是由陆壳或来源于陆壳的沉积物熔融而成的.这些关系说明,这种微花岗岩是在志留纪,即大陆基底上方的英?岩在奥陶纪发生迁移之后产生的.
The Coney Head complex in the White Bay area of Newfoundland is composed of allochthonous plutons that invaded the continental margins during the Ordovician Taikang orogeny and deformed equivalent rocks that are thought to consist of part of an arc The melting age of the formed amphibolite was 472 ± 2 Ma, indicating that the amphibolite crystallized during the Arenig period and there is a U / Pb (zircon + rutile) age of 433 ± 2 μm of micro-granulation cut amphibolite.The residual metamorphic zircons in micritic granites indicate that some of the magmatic rocks are melted by the continental crust or sediments derived from the continental crust.These relationships suggest that The micro-granites were produced after the migration of the Ordovician in the Silurian, the continental rock above the continental basement.