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Sample SM-75-38A
NavDat sample number 8388 · RHYOLITE
Sample
| Sample ID | SM-75-38A |
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| 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 | Cream to pink to buff colored lava, often pumiceous; plagioclase An30-50 with strongly resorbed margins, orthopyroxene, clinopyroxene, and titanomagnetite phenocrysts set in a pilotaxitic partially devitrified groundmass consisting of plagioclase microlites, opaque granules, and pale brown glass. |
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Location
| Latitude | 41.6828 |
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| Longitude | -121.592 |
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| State / province | California |
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| Volcanic field | Medicine Lake Highland |
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| Location comment | 1/2 mi SE of Cinder Butte along the roadbed of the abandoned lumber railroad track |
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Age
| Age (Ma) | Error | Min | Max | Geologic age | Dated by |
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| 0.33 |
|
0.29 |
0.37 |
|
|
Analyses
Whole rock
| Item | Value | Std. dev. | Unit | Method |
|---|
| SIO2 | 71.99 | | WT% | XRF |
| AL2O3 | 14.11 | | WT% | XRF |
| FEO | 0.6 | | WT% | XRF |
| FE2O3 | 2.23 | | WT% | XRF |
| TIO2 | 0.45 | | WT% | XRF |
| MNO | 0.05 | | WT% | XRF |
| MGO | 0.34 | | WT% | XRF |
| CAO | 1.24 | | WT% | XRF |
| NA2O | 3.91 | | WT% | XRF |
| K2O | 4.52 | | WT% | XRF |
| P2O5 | 0.08 | | WT% | XRF |
