“…The Lake George samples in the Northeast Tanacross map area include a higher proportion of MORB basalts exhibiting less crustal contamination compared to those in the Ladue River-Mount Fairplay area, and the Northeast Tanacross area also includes more numerous interlayered amphibolites, which may be a result of differing proximity to eruptive centers during continental rifting. Some amphibolites from the Lake George assemblage collected from the northeastern Tanacross quadrangle from different sample localities than from those reported in Wypych and others (2017;2018), as well as some from the Big Delta and Healy quadrangles west and southwest of our study area, respectively, have within-plate (OIB) trace-element signatures (Dusel-Bacon and Cooper, 1999;Dusel-Bacon and others, 2004) indicative of rifting.…”