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Sample SW-75-164
NavDat sample number 8383 · DACITE
Sample
| Sample ID | SW-75-164 |
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| Rock name | DACITE |
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| Rock type | VOLCANIC |
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| Composition | FELSIC |
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| Material | IGNEOUS |
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| Comment | Gray vesiculated lava to black obsidian; plagioclase An40-70, orthopyroxene, clinopyroxene, and titanomagnetite phenocrysts set in a trachytic to hyalotrachytic groundmass of fresh brown glass. |
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Location
| Latitude | 41.5213 |
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| Longitude | -121.777 |
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| State / province | California |
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| Volcanic field | Medicine Lake Highland |
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| Location comment | 1/4 mi SE of Lost Spring on Fisk Ridge |
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Age
| Age (Ma) | Error | Min | Max | Geologic age | Dated by |
|---|
| 0.05 |
|
0.005 |
0.15 |
|
|
Analyses
Whole rock
| Item | Value | Std. dev. | Unit | Method |
|---|
| SIO2 | 68.03 | | WT% | XRF |
| AL2O3 | 16.01 | | WT% | XRF |
| FEO | 1.89 | | WT% | XRF |
| FE2O3 | 1.5 | | WT% | XRF |
| TIO2 | 0.63 | | WT% | XRF |
| MNO | 0.07 | | WT% | XRF |
| MGO | 0.72 | | WT% | XRF |
| CAO | 2.54 | | WT% | XRF |
| NA2O | 4.71 | | WT% | XRF |
| K2O | 3.42 | | WT% | XRF |
| P2O5 | 0.13 | | WT% | XRF |
