Sample: 74-ALe-66
Sample ID: | 74-ALe-66 [1] |
Station ID: | 74-ALe-66 |
AT Num: | |
Volcano: | |
Possible source: | |
Eruption: | |
Collector: | Unknown, Unknown |
Date sampled: | 1974-00-00 |
Sample type 1: | Lava |
Color: | |
Final unit: | |
Text Description: | Unassigned rocks, older rhyolite dome (Pleistocene). Pinkish-gray, sparsely porphyritic rhyolite that contains 1-2% phenocrysts of plagioclase, opaque minerals, and possibly some altered mafic minerals, in microfelty groundmass of feldspar. Only exposed in one locality near northwest corner of quadrangle. * * * Whole-rock K-Ar age is 1.23+/-0.07 Ma. |
Sample Location: |