Rb-Sr Dating of Feldspar in Till

Feldspar in Cenozoic till on the summit of Table Mountain (77°57 S, 162°00 E) south of the upper Ferrar Glacier (Barrett and Powell 1981) yielded a Rb-Sr date of 524 115 Ma from line B in Fig. 19.15 and an initial ratio of 0.7132 0.0068. Both 

Improvements in the technology of analytical instruments that have occurred since the measurements in Table 19.5 were made permit individual mineral grains to be dated by the Rb- Sr, Ar/ Ar, and U-Pb methods. The crystallization ages of selected mineral grains in till 

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