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Sample S92-H261
NavDat sample number 37048 · BASALT
Sample
| Sample ID | S92-H261 |
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| Rock name | BASALT |
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| Rock type | VOLCANIC |
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| Composition | MAFIC |
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| Material | IGNEOUS |
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| Comment | Lava flow collected from outcrop 0.2 km south of North Lake. Reversed-polarity measured from adjacent outcrop 30 m south along strike, but dated sample is from outcroptoo greatly frost-heaved to measure polarity. Two petrographically similar lava flows exposed successively downslope from this flow are also reversely polarized. Geomorphically, area sampled is part of the dissected remains of a shield volcano centered at Green Point Mountain. Plagioclase 3-4% and olivine 3% phenocrysts in an intergranular groundmass of plagioclase, augite, and opaque minerals; essentially alteration free. |
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Location
| Latitude | 45.6397 |
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| Longitude | -121.757 |
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| State / province | Oregon |
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Age
| Age (Ma) | Error | Min | Max | Geologic age | Dated by |
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| 2.64 |
|
2.53 |
2.75 |
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Analyses
No chemical analyses are stored for this sample.
