Tectonic constraints to Cretaceous magmatic arc deduced from detrital heavy minerals in northeastern Japan – evidence from detrital garnets, tourmalines and chromian spinels

Mayuko Nishio, Kohki Yoshida
2014 Cretaceous research (Print)  
North Kitakami Terrane origin, and detrital tourmalines are considered to have 32 been derived mainly from meta-sedimentary rocks. The composition of detrital 33 chromian spinels are compositionally diverse and mainly derived from tholeiitic 34 and intra-plate basalts showing high TiO2 (>about 1.0 wt%) and island arc 35 basalts with moderately low TiO2 (1.0> TiO2 >0.5 wt%) and high -Cr#. Latter 36 chromian spinels can be considered as a record of island arc activity including 37 high
more » ... in Early Cretaceous time. Because adequate source rocks of 38 the spinels are elusive near the basin compared with those of detrital garnets 39 and tourmalines, these rocks are believed to have been disturbed by Cenozoic 40 tectonics and eroded and covered by newly formed volcanic and sedimentary 41 rocks. 42
doi:10.1016/j.cretres.2013.11.004 fatcat:p2y2br6cjzcqrc7tphaeysgy4e