Sample RP-2
NavDat sample number 4784 · RHYOLITE
Sample
| Sample ID | RP-2 |
|---|---|
| Rock name | RHYOLITE |
| Rock type | VOLCANIC |
| Composition | FELSIC |
| Material | IGNEOUS |
| Comment | 70 to 75% aphanitic groundmass of equal proportions of albite and orthoclase, along with quartz; groundmass also contains 2% to 3% opaques; phenocrysts are anorthoclase laths |
Location
| Latitude | 44.4047 |
|---|---|
| Longitude | -103.682 |
| State / province | South Dakota |
| Volcanic field | Black Hills Tertiary igneous province |
Age
| Age (Ma) | Error | Min | Max | Geologic age | Dated by |
|---|---|---|---|---|---|
| 54 | 50 | 58 |
Analyses
Whole rock
| Item | Value | Std. dev. | Unit | Method |
|---|---|---|---|---|
| SIO2 | 71.61 | WT% | NAA | |
| AL2O3 | 15.6 | WT% | NAA | |
| FE2O3 | 1.26 | WT% | NAA | |
| MGO | 2.24 | WT% | NAA | |
| CAO | 0.33 | WT% | NAA | |
| NA2O | 3.62 | WT% | NAA | |
| K2O | 5.07 | WT% | NAA | |
| TIO2 | 0.18 | WT% | NAA | |
| MNO | 0.02 | WT% | NAA | |
| BAO | 0.07 | WT% | NAA | |
| BA | 670.9 | PPM | NAA | |
| CE | 170 | PPM | NAA | |
| CO | 1.6 | PPM | NAA | |
| EU | 1.4 | PPM | NAA | |
| HF | 11.4 | PPM | NAA | |
| LA | 49.4 | PPM | NAA | |
| LU | 0.6 | PPM | NAA | |
| RB | 463.8 | PPM | NAA | |
| SC | 0.3 | PPM | NAA | |
| SM | 5.5 | PPM | NAA | |
| TH | 83.8 | PPM | NAA | |
| V | 21 | PPM | NAA | |
| YB | 4 | PPM | NAA |