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Sample USGSD-M881-1
NavDat sample number 10029 · GRANODIORITE
Sample
| Sample ID | USGSD-M881-1 |
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| Rock name | GRANODIORITE |
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| Rock type | PLUTONIC |
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| Composition | INTERMEDIATE |
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| Material | IGNEOUS |
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| Comment | medium to coarse grained, generally uniformly textured; prominent hornblende and biotite, sphene, and large K-feldspar megacrysts that are anhedral and inclusion-rich; from a transition zone between a granite and granodiorite where magmatic mixing probably occurred; weak foliation defined by mafic minerals present |
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Location
| Latitude | 45.5267 |
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| Longitude | -112.935 |
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| Location | loose block at 8700 ft elevation at base of high cliffs, S face of 9330 ft knob; Beaverhead County |
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| State / province | Montana |
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| Volcanic field | Pioneer Batholith |
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Age
| Age (Ma) | Error | Min | Max | Geologic age | Dated by |
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| 72 |
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69.5 |
74.5 |
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|
Analyses
No chemical analyses are stored for this sample.
