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Sample 82-19
NavDat sample number 10024 · DACITE
Sample
| Sample ID | 82-19 |
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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 | Black glassy rock on fresh surfaces, dull black to dark gray on perlitic surfaces; plagioclase An30-50, orthopyroxene, and titanomagnetite phenocrysts 0.3-1 mm set in a hyalotrachytic groundmass consisting of numerous feldspar microlites set in clear fresh glass. |
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Location
| Latitude | 41.6031 |
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| Longitude | -121.446 |
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| State / province | California |
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| Volcanic field | Medicine Lake Highland |
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Age
| Age (Ma) | Error | Min | Max | Geologic age | Dated by |
|---|
| 0.1 |
|
0.09 |
0.11 |
|
|
Analyses
Whole rock
| Item | Value | Std. dev. | Unit | Method |
|---|
| SIO2 | 68.72 | | WT% | XRF |
| AL2O3 | 15.52 | | WT% | XRF |
| FEO | 2.18 | | WT% | XRF |
| FE2O3 | 1.17 | | WT% | XRF |
| TIO2 | 0.63 | | WT% | XRF |
| MNO | 0.06 | | WT% | XRF |
| MGO | 0.94 | | WT% | XRF |
| CAO | 2.43 | | WT% | XRF |
| NA2O | 4.61 | | WT% | XRF |
| K2O | 3.74 | | WT% | XRF |
| P2O5 | 0.12 | | WT% | XRF |
