Geochemestry of basic magmatism on Byers Peninsula, Antarctica

In this field campaign 59 samples of volcanic and subvolcanic rocks were
collected. Ten of these samples were analyzed via ICP at the Department of
Geology, U. de Chile. The samples are subalkaline rocks ranging in composition
between basalt and rhyolite, with a predominance of basaltic to
"basaltic-andesitic" magnetism with transitional affinities between tholeitic
and calcalkine. The rocks show a high degree of fractionation and high rates
of partial fusion, indicating origin in an island arc tectonic setting. The
magnetism of the arc probably occurred during the early Cretaceous to the
early Tertiary.