B 2143 Figure 35

Figure 35. The 39Ar release pattern of incremental heating of hornblende from a quartz monzonite rock, sample 8B53-1, collected near Hejao, showing a plateau Ar40Ar/39Ar Caledonian age of 455.0+-3.4 Ma (J.E. Conrad and E.H. McKee, unpub. data, 1990).

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