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Sample Y-5780
NavDat sample number 2917 · TRACHYANDESITE
Sample
| Sample ID | Y-5780 |
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| Rock name | TRACHYANDESITE |
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| Rock type | VOLCANIC |
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| Composition | INTERMEDIATE |
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| Material | IGNEOUS |
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| Collected by | Charles J. Vitaliano |
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| Comment | A black, aphanitic, slightly vesicular rock. Microphenocrysts <1mm constitute 55% of the rock. Zoned plagioclase An55-61 is the predominant microphenocryst mineral about 5/6 of the microphenocrysts; some of the crystals are corroded and replaced by glass. Augite forms euhedral crystals, occasionally showing zones of resorption. Olivine completely iddingsitized is extremely rare as microphenocrysts. The groundmass consists of plagioclase, completely iddingsitized olivine, and augite microlites; minute grains of magnetite; and glass 5%. Vesicles are sometimes lined with cristobalite. See Y-B3-13. |
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Location
| Latitude | 38.1931 |
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| Longitude | -117.119 |
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| Location | Nye County, NV |
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| State / province | Nevada |
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| Volcanic field | Goldfield-Tonopah region, West-Central Nevada |
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| Location comment | Olivine trachyandesite flow on the W drainage of a small valley 2 1/2 mi W of the Rye Patch pump station near Tonopah |
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Age
| Age (Ma) | Error | Min | Max | Geologic age | Dated by |
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| 16.2 |
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14.2 |
18.2 |
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Analyses
No chemical analyses are stored for this sample.
