Sample PM-34

NavDat sample number 31340 · ANDESITE

Sample

Sample ID	PM-34
Rock name	ANDESITE
Rock type	VOLCANIC
Composition	INTERMEDIATE
Material	IGNEOUS
Comment	Porphyritic , hornblende-bearing andesite with phenocrysts of plagioclase, hornblende, and hypershtene (commonly rimmed by augite) embedded in a pilotaxitic groundmass of plagioclase, clinopyroxene, orthpyroxene, Fe-Ti oxides, and glass. Hornblende and plagioclase are commonly glomerocrystic. Xenocrysts are quartz, seived plagioclase, and minor orthopyroxene. Xenoliths are equigranular, gabbroic, and consist of plagioclase, pyroxene, and hornblende.

Age (Ma)	Error	Min	Max	Geologic age	Dated by
45.6		37.4	53.8

Item	Value	Unit	Method
SIO2	59.28	WT%	XRF
TIO2	1.15	WT%	XRF
AL2O3	17.31	WT%	SRC AND AAS
FEO	7.2	WT%	XRF
MNO	0.12	WT%	XRF
MGO	4.06	WT%	SRC AND AAS
CAO	6.32	WT%	XRF
NA2O	3.86	WT%	SRC AND AAS
K2O	1.44	WT%	XRF
P2O5	0.33	WT%	XRF
TOTAL	101.07	WT%	XRF
RB	47	PPM	XRF
SR	404	PPM	XRF
Y	27	PPM	XRF
ZR	228	PPM	XRF
BA	530	PPM	XRF
V	125	PPM	XRF
CR	140	PPM	XRF
NI	45	PPM	XRF
SR87_SR86	0.704044		ICPMS