In the previous section I proposed that Archean granitoids, like those of the present day, formed mainly in subduction settings. Two questions can now be posed. First, was the tectonic process that generated the continental crust invariant through all of geological time and second, was the rate of growth of the crustal constant or did it vary?

Figure 7.1 is a compilation of U-Pb zircon ages of rocks and minerals of the continental crust, reproduced from Condie and Aster (2010). It shows these ages are not distributed uniformly through geological time but are grouped in a number of prominent...

First Page Preview

First page PDF preview
You do not currently have access to this article.