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Sample 5

NavDat sample number 4455 · PHONOLITE

Sample

Sample ID5
Rock namePHONOLITE
Rock typePLUTONIC
CompositionINTERMEDIATE
MaterialIGNEOUS
Commentporphyritic with phenocrysts of orthoclase exsolved to albite, aegerine-augite; groundmass is trachytic and composed of aegerine augite and analcime or sodalite

Location

Latitude44.3312
Longitude-103.806
LocationGreen Mountain
State / provinceSouth Dakota
Volcanic fieldGreen Mountain phonolite

Age

Age (Ma)ErrorMinMaxGeologic ageDated by
50 45 55

Analyses

Whole rock

ItemValueStd. dev.UnitMethod
SIO246WT%GRAV
NA2O8WT%AAS
MGO0.045WT%AAS
K2O4WT%AAS
CAO0.28WT%AAS
SR87_SR860.7053MS

References