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Sample AH-80-139
NavDat sample number 8394 · RHYOLITE
Sample
| Sample ID | AH-80-139 |
|---|
| 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 strikingly developed. The banding is made obvious by alternating layers of glass and microlites that are strongly flow aligned. |
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Location
| Latitude | 41.5214 |
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| Longitude | -121.7 |
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| State / province | California |
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| Volcanic field | Medicine Lake Highland |
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| Location comment | 0.5 mi SW of Grasshoper Flat and 1/2 mi due E of hill 5866 |
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Age
| Age (Ma) | Error | Min | Max | Geologic age | Dated by |
|---|
| 0.33 |
|
0.31 |
0.35 |
|
|
Analyses
Whole rock
| Item | Value | Std. dev. | Unit | Method |
|---|
| SIO2 | 76.74 | | WT% | XRF |
| AL2O3 | 12.82 | | WT% | XRF |
| FEO | 1 | | WT% | XRF |
| FE2O3 | 0.26 | | WT% | XRF |
| TIO2 | 0.2 | | WT% | XRF |
| MNO | 0.03 | | WT% | XRF |
| MGO | 0.35 | | WT% | XRF |
| CAO | 0.89 | | WT% | XRF |
| NA2O | 3.67 | | WT% | XRF |
| K2O | 4.39 | | WT% | XRF |
| P2O5 | 0.03 | | WT% | XRF |
