Figure 13. Comparison of
3He and
4He concentrations in whole-samples (melt) and in
vehicles (mill).
Milling (Section 3.1) generally liberates a considerable portion of
3He (Average and
Median
0.4) and a smaller portion of
4He (Av and Me
0.1). This comparison
shows that
3He-bearing vesicles are larger and can be open (by milling) easier than
radiation damage tracks containing radiogenic
4He.