Table 3

Mount Hamilton Franciscan40Ar/39Ar phengite ages, with ±1σ uncertainties. The 32 Mount Hamilton samples together average 139 ± 6 My with a MSWD of 17. See Fig. 2 for average ages and MSWD for each sample. For each sample, numbers in parentheses indicate the grain and spot number, respectively.

SampleAge (My)
Eclogite and garnet amphibolite
MH-90-1AB (1-1)135.6 ± 1.4
MH-90-1AB (1-3)138.3 ± 1.3
MH-90-1AB (2-2)143.3 ± 1.1
MH-90-1AB (2-1)143.5 ± 1.4
MH-90-1AB (1-2)144.7 ± 1.0
MH-90-01AA (3-1)129.4 ± 11.9
MH-90-01AA (1-1)143.9 ± 0.9
MH-90-01AA (1-3)146.4 ± 1.2
MH-90-01AA (1-2)147.6 ± 1.2
Transition zones and rinds
MH-90-11C (1-1)133.5 ± 3.3
MH-90-11C (2-1)141.5 ± 2.2
MH-90-11C (1-2)145.1 ± 1.3
MH-90-11C (2-2)146.8 ± 2.2
MH-90-11C (2-3)147.5 ± 0.9
MH-90-11C (1-4)148.2 ± 1.2
MH-90-11C (1-3)148.7 ± 1.3
MH-90-09 (2-1)99.8 ± 10.2
MH-90-09 (2-3)129 ± 20
MH-90-09 (2-4)132.3 ± 2.5
MH-90-09 (2-2)137.6 ± 3.2
MH-90-09 (1-1)143.6 ± 2.0
MH-90-09 (1-2)145.3 ± 2.9
GL-16-01 (1-2)122.5 ± 9.0
GL-16-01 (1-1)128.4 ± 17.1
GL-16-01 (2-2)142.4 ± 4.1
GL-16-01 (2-3)143.6 ± 7.6
GL-16-01 (2-1)143.8 ± 1.8
GL-16-04 (2-2)114.1 ± 8.2
GL-16-04 (1-1)136.9 ± 7.5
GL-16-04 (1-3)141.9 ± 1.8
GL-16-04 (1-2)145.0 ± 5.9
GL-16-04 (2-1)148.1 ± 3.6