Occurrence and Origin of Garnet in the South Mountain Batholith

Abstract

Garnet occurs around the margin of the South Mountain batholith as an accessory mineral in three distinct comagmatic phases. Electron microprobe analyses and textural relationships of 50 garnet-biotite pairs indicates that garnet had two origins. Garnet associated with xenoliths in biotite granodiorite or monzogranite are interpreted as being metamorphic in origin, and garnet from the groundmass of monzogranite and leucocratic monzogranite aplite are considered to be primary.

Keywords: Pages: 75 Supervisor: D. B. Clarke