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Sample T037

NavDat sample number 6903 · TRACHYTE

Sample

Sample IDT037
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 trachytic texture, interstitial quartz; glomerophyric

Location

Latitude44.3703
Longitude-104.039
LocationBlack Hills
State / provinceSouth Dakota
Volcanic fieldTinton District

Age

Age (Ma)ErrorMinMaxGeologic ageDated by
48 38 59

Analyses

Whole rock

ItemValueStd. dev.UnitMethod
SIO267.1WT%EPMA
AL2O317.55WT%EPMA
FE2O31.81WT%EPMA
FEO0.32WT%EPMA
MGO0.29WT%EPMA
CAO0.8WT%EPMA
NA2O6.34WT%EPMA
K2O4.99WT%EPMA
TIO20.31WT%EPMA
P2O50.21WT%EPMA
MNO0.11WT%EPMA
SO30.16WT%EPMA

References