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Sample USGSD-Dodgson Creek

NavDat sample number 10041 · TONALITE

Sample

Sample IDUSGSD-Dodgson Creek
Rock nameTONALITE
Rock typePLUTONIC
CompositionINTERMEDIATE
MaterialIGNEOUS
Commentmedium to fine grained, uniformly textured, dark-bluish-gray; equant and euhedral hornblende and biotite show against background of plagioclase and quartz; no primary foliation; sample from near intrusive contact; DATES GIVEN BY HORNBLENDE ARE SPURIOUS; ZIRCON DATE IS TOO YOUNG

Location

Latitude45.8686
Longitude-112.992
Locationoutcrop at 7100 ft elevation on ridge between Dodgson Creek and a tributary to the east; Silver Bow County
State / provinceMontana
Volcanic fieldPioneer Batholith

Age

Age (Ma)ErrorMinMaxGeologic ageDated by
98.8 96 101.6

Analyses

No chemical analyses are stored for this sample.

References