122: Volcanic activity on Akutan Island since 1790

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123: Modal analyses based on four 500 point counts of each sample. * Values are in volume percent. Plag = plagioclase, Olv = olivine, Cpx = clinopyroxene, Opq = opaques, and GM = groundmass. *

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124: Results from Clinopyroxene compositional estimates based on d-spacing of 311 reflection.

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125: Modal analyses for western Akutan lavas * (D) = dike, (U) = upper series, (L) = lower series, Plag = plagioclase, Olv = olivine, Cpx = clinopyroxene, Opx = orthopyroxene, Opq = opaques, and GM = groundmass. *

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126: Modal analyses for eastern and central Akutan lavas * H.S.V. = Hot Springs Bay Valley, Op.Bt. = Open Bight, P.V. = Pickup Valley, I = intrusive, F = lava flow, D = dike, Plag = plagioclase, Olv = olivine, Cpx = clinopyroxene, Opx = orthopyroxene, Opq = opaques, Alt = alteration minerals, and GM = groundmass *

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127: Crystallization sequence for western Akutan lavas

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128: Crystallization sequence for eastern and central Akutan lavas

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129: Posterior probabilities for the four groups of lavas distinguished by the cluster analysis

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130: Neodymium and strontium data for Akutan Island * Data from McCulloch and Perfit (1981) and Perfit (unpublished data). Errors are in the last figures given and represent +/- 2 sigma mean. *

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131: Whole rock K-Ar dates for Akutan lavas

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132: Geothermometry for Akutan mineral pairs * *Wood and Banno (1973) geothermometer. **Wells (1977) geothermometer. # at 1 bar pressure *

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133: Normative oxides and normative minerals (in weight percent)

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134: Microprobe data for Akutan lavas

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135: Rb and Sr analyses * Samples AK-81-8A and 8B, and AK-81-52A and 52B were duplicates submitted to test the reproducibility of the analyses *

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136: Petrographic descriptions of Akutan lavas

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