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Sample AH-80-83
NavDat sample number 8390 · RHYOLITE
Sample
| Sample ID | AH-80-83 |
|---|
| Rock name | RHYOLITE |
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| Rock type | VOLCANIC |
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| Composition | FELSIC |
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| Material | IGNEOUS |
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| Comment | Obsidian sample, no phenocrysts; fluidal banding is prominently displayed by alternation of glassy and cryptocrystalline layers, the latter possessing trachytic trains of microlites. |
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Location
| Latitude | 41.4631 |
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| Longitude | -121.714 |
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| State / province | California |
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| Volcanic field | Medicine Lake Highland |
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| Location comment | 3.2 mi SE of the summit of Doe Peak; outcrop is poor and consists of infrequent knockers of obsidian |
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Age
| Age (Ma) | Error | Min | Max | Geologic age | Dated by |
|---|
| 0.29 |
|
0.27 |
0.31 |
|
|
Analyses
Whole rock
| Item | Value | Std. dev. | Unit | Method |
|---|
| SIO2 | 74.12 | | WT% | XRF |
| AL2O3 | 13.35 | | WT% | XRF |
| FEO | 0.83 | | WT% | XRF |
| FE2O3 | 0.61 | | WT% | XRF |
| TIO2 | 0.22 | | WT% | XRF |
| MNO | 0.04 | | WT% | XRF |
| MGO | 0.16 | | WT% | XRF |
| CAO | 0.91 | | WT% | XRF |
| NA2O | 3.84 | | WT% | XRF |
| K2O | 4.54 | | WT% | XRF |
| P2O5 | 0.03 | | WT% | XRF |
