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Sample T165

NavDat sample number 6898 · TRACHYTE

Sample

Sample IDT165
Rock nameTRACHYTE
Rock typeVOLCANIC
CompositionINTERMEDIATE
MaterialIGNEOUS
Commentaphanitic holocrystalline groundmass with phenocrysts of plagioclase, hornblende, biotite, and rare aegirine-augite; groundmass composed of lath-shaped orthoclase arranged in pilotaxitic texture, interstitial quartz; glomerophyric

Location

Latitude44.3717
Longitude-104.034
LocationBlack Hills
State / provinceSouth Dakota
Volcanic fieldTinton District

Age

Age (Ma)ErrorMinMaxGeologic ageDated by
48 38 59

Analyses

Whole rock

ItemValueStd. dev.UnitMethod
SIO262.88WT%EPMA
AL2O318.41WT%EPMA
FE2O32.08WT%EPMA
FEO3.31WT%EPMA
MGO1.56WT%EPMA
CAO1.1WT%EPMA
NA2O5.64WT%EPMA
K2O3.93WT%EPMA
TIO20.57WT%EPMA
P2O50.22WT%EPMA
MNO0.22WT%EPMA
SO30.13WT%EPMA

References