Geochemical interpretation of samples of igneous rocks from northeast Tanacross

Geochemistry of the igneous rocks in the Ladue River-Mount Fairplay area

“…8D and E). Trace element composition of Kpg and Kg are in agreement with the Kg unit of the Northeast Tanacross map area (Wypych, 2021), but separate fractionation trends on Zr plots (fig. 8F) suggest differences in zircon fractionation between the two units.…”

“…The trace-element composition of lKfv generally overlaps that of the other felsic samples (figs. 6A-F) and is comparable to that of the most siliceous Kv samples (Wypych, 2021). Late Cretaceous porphyritic granite (lKpg) is characterized by its elevated magnesian character compared to other igneous rocks of similar silica composition in the map area (fig.…”

“…4C and F). In the Northeast Tanacross map area, we observed syn-collisional as well as within-plate granitoids within the Kg group (Wypych, 2021).…”

“…6A-F). In terms of major-element composition, unit lKgd follows the Ktgd unit of the Northeast Tanacross map area (Wypych, 2021). However, the trace element composition of unit lKgd suggests a better correlation to the Pika diorite (Kpd) unit in the Northeast Tanacross map area (figs.…”

Geologic investigation of the Ladue River-Mount Fairplay area, eastern Alaska

“…The trace-element composition of lKfv generally overlaps that of the other felsic samples (figs. 6A-F) and is comparable to that of the most siliceous Kv samples (Wypych, 2021). Late Cretaceous porphyritic granite (lKpg) is characterized by its elevated magnesian character compared to other igneous rocks of similar silica composition in the map area (fig.…”