What possible explanations can be considered for Highly Radiogenic Sr-isotopic signature of a suite of volcanic rocks?

I am working on a suite of volcanic rocks which exhibit high initial 87Sr/86Sr ratio. In some samples the ratio is as high as 0.749267 ( and 143Nd/144Nd = 0.512580). Geochemically, the samples...

05 May 2019 9,865 2 View