Sample 100

NavDat sample number 11364 · TRACHYTE

Sample

Sample ID	100
Rock name	TRACHYTE
Rock type	VOLCANIC
Composition	INTERMEDIATE
Material	IGNEOUS
Comment	porphyritic; phenocrysts form flow foliation; holocrystalline matrix of anorthoclase-Na sanidine, clinopyroxene, and magnetite; phenocrysts are feldspar, amphibole, pyroxene, magnetite-ulvospinel, and minor biotite

Location

Latitude	42.7211
Longitude	-107.304
Location	Rattlesnake Hills
State / province	Wyoming
Volcanic field	alkali trachyte

Age

Age (Ma)	Error	Min	Max	Geologic age	Dated by
43.6		41.4	46.6

Analyses

Whole rock

Item	Value	Std. dev.	Unit	Method
SIO2	59.66		WT%	XRF
AL2O3	18.81		WT%	XRF
FE2O3	2.8		WT%	XRF
FEO	1.06		WT%	TIT
CAO	3.9		WT%	XRF
MGO	0.82		WT%	XRF
NA2O	5.82		WT%	XRF
K2O	4.72		WT%	XRF
TIO2	0.56		WT%	XRF
MNO	0.15		WT%	XRF
P2O5	0.13		WT%	XRF
H2O	1.36		WT%	PENFIELD
CO2	0.76		WT%	GRAV
TOTAL	100.55		WT%	XRF
RB	104		PPM	XRF
SR	1591		PPM	XRF
Y	29		PPM	XRF
ZR	417		PPM	XRF
LA	61		PPM	XRF

References

Stupak, William A (1984)