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Sample 3-26-89-6
NavDat sample number 30302 · TUFF
Sample
| Sample ID | 3-26-89-6 |
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| Rock name | TUFF |
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| Rock type | VOLCANIC |
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| Composition | FELSIC |
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| Material | IGNEOUS |
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| Comment | on south-facing slope, at southeast end of nw-se oriented ridge, northwest side of Zapato Chino Canyon; elevation 1,150 ft or 350 m. Buff-white to light-gray, finegrained crytal vitric tuff with silt laminae; bubblewall glass shards approximately0.01-0.02 mm are well preserved; contains angular to subangular crystals approximately 0.005 - 0.03 mm of quartz, biotite, hornblende, plagioclase, and opaque minerals; 85% glass, 10% clay laminae, 5% crystals; tuff unit is thin bedded to laminated; lower contact is sharp and planar to slightly undulatory, upper contact is bioturbated; 5ft 1.5 m thick;glass shards in tuff are well preserved and are isotropic in thin section; K content derived from K-Ar analysis is consistent with K content determined from microprobe analyses; this age is considered to be reliable |
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Location
| Latitude | 36.015 |
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| Longitude | -120.286 |
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| Location | Etchegoin Formation |
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| State / province | California |
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Age
| Age (Ma) | Error | Min | Max | Geologic age | Dated by |
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| 5 |
|
4.7 |
5.3 |
|
|
