Paleosalinity of Permian Nonmarine Deposits in Antarctica

Abstract
Argillites of the Permian Mount Glossopteris Formation were analyzed for clay minerals, trace elements, and phosphate paleosalinity. Mainly degraded and stripped illites occur. The determined salinity range, 29 to 33 parts per mille is designated the "paleosalinity signature" of the formation. Analysis of trace elements supports phosphate paleosalinity determinations. Data from Leaia-bearing beds indicate a salinity range of 30 to 31 parts per mille that persisted some 137 years. Subsequent increase to 33 parts per mille corresponded to termination of leaiid occupancy of the area. These findings confirm and extend Nelson's study of phasphate paleosalinity.