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Sample 122ss
NavDat sample number 15253 · SYENITE
Sample
| Sample ID | 122ss |
|---|
| Rock name | SYENITE |
|---|
| Rock type | PLUTONIC |
|---|
| Composition | INTERMEDIATE |
|---|
| Material | IGNEOUS |
|---|
| Comment | cap syenite; medium to coarse grained ?; K-feldspar, prismatic augite, occasionally replaced with sodalite and hornblende; rare biotite, magnetite, and apatite |
Location
| Latitude | 47.47 |
|---|
| Longitude | -110.24 |
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| Location | Square Butte |
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| State / province | Montana |
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| Volcanic field | Square Butte laccolith of Central Montana Alkalic Province |
Age
| Age (Ma) | Error | Min | Max | Geologic age | Dated by |
| 44.5 |
|
34 |
55 |
|
|