Sample: 54-D-44
| Sample ID: | 54-D-44 [1] |
| Station ID: | 54-D-44 |
| AT Num: | |
| Volcano: | Makushin |
| Possible source: | |
| Eruption: | |
| Collector: | Drewes, Harald |
| Date sampled: | 1954-01-01 |
| Sample type 1: | Lava |
| Color: | |
| Final unit: | |
| Text Description: | Andesite porphyry from the Makushin volcanics 3 miles southeast of Sugarloaf Cone. It is medium gray to purplish gray and contains plagioclase and pyroxene phenocrysts 1-4 millimeters long. Phenocrysts compose 20 percent of the rock: 12 percent andesine to bytownite, which forms euhedral laths and fragments, and which has normal and oscillatory zones, zones of dusty inclusions, and apatite inclusions; 5 percent augite(?), which forms euhedral to anhedral grains, crystal clusters, and reaction rims around hypersthene; 2 percent subhedral hypersthene with reaction rims; a trace of anhedral olivine(?); a trace of subhedral to anhedral magnetite; and a trace of euhedral apatite. The groundmass has a felty to flow texture and includes abundant subhedral andesine laths, much augite(?), and a trace of a granular black opaque mineral. |
| Sample Location: |
References Cited
[1] Geology of Unalaska Island and adjacent insular shelf, Aleutian Islands, Alaska, 1961
Drewes, Harald, Fraser, G. D., Snyder, G. L., and Barnett, H. F. Jr., 1961, Geology of Unalaska Island and adjacent insular shelf, Aleutian Islands, Alaska: in Investigations of Alaskan volcanoes, U.S. Geological Survey Bulletin 1028-S, p. 583-676, 3 sheets, scale 2 at 1:250,000 and 1 unknown.
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plate 75 PDF 6.7 MB
plate 76 PDF 113 KB
plate 77 PDF 250 KB
table 1 PDF 326 KB