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SAMPLE INFO : Snyder_1959_10

Sample ID:	Snyder_1959_10
Station ID:	Snyder_1959_10
Latitude:	51.9531
Longitude:	178.5356
Datum:	NAD83
Sample Type 1:	Lava
Field Lithology:	Dacite

Text Description:
High-silica dacite of Double Point dacite. Color: medium dark gray (N 4). Texture: hypocrystalline, porphyritic with blocky feldspar phenocrysts with maximum diameter of 5 mm. Eleven sections of the plagioclase, 25-30 percent, perpendicular to both albite twinning and basal cleavage give anorthite contents that appear to be distributed evenly from An23 to A55; complex zones and intergrowths common; groundmass microlites may group around An17 but cannot be determined accurately; two-fluid inclusions from 0.004-0.02 mm in diameter occupy negative crystals in certain zones of the feldspar. Stubby euhedral hypersthene, 5-10 percent, is pleochroic in light pink and light green. Accessories are clinopyroxene, 1 percent; magnetite, 2 percent; oxyhornblende, 1 percent; and tridymite, 1 percent. Fluidal groundmass glass has N=1.504(?).

References:

Geology of Little Sitkin Island, Alaska

GEOCHEM DATA

StationID	Latitude	Longitude	Geologist	DateVisited	Age Info	Volcano	Eruption	Location Description	Text Description	Sample ID	Sample Type 1	Sample Type 2	Final Unit	Material	SiO2	TiO2	Al2O3	FeOT	MnO	MgO	CaO	Na2O	K2O	P2O5	Total-majors	REF majors	METH majors	Fe2O3/Fe203T orig	FeO/FeOT orig	Volatiles csv	METH volatiles	Cs	Rb	Ba	Sr	La	Ce	Pr	Nd	Sm	Eu	Gd	Tb	Dy	Ho	Er	Tm	Yb	Lu	Y	Zr	Nb	Hf	Ta	Pb	Th	U	Sc	V	Cr	Fe	Co	Ni	Cu	Zn	Ga	Mo	As	Na	K	Ref trace1	METH trace1	Rb	Ba	Sr	La	Ce	Nd	Sm	Eu	Gd	Dy	Er	Yb	Lu	Y	Zr	Nb	Pb	Th	U	Sc	Ti	V	Cr	Ni	Cu	Zn	Ga	Ref trace2	METH trace2	Light csv	Halogen csv	other major csv	other lile csv	other ree csv	other hfse csv	other hpe csv	other tm csv	other misc csv
Snyder_1959_10	51.9531	178.5356	Snyder, G. L.			Little Sitkin		From small inlier of Double Point dacite about 1 mile west-northwestward of summit of Little Sitkin volcano	High-silica dacite of Double Point dacite. Color: medium dark gray (N 4). Texture: hypocrystalline, porphyritic with blocky feldspar phenocrysts with maximum diameter of 5 mm. Eleven sections of the plagioclase, 25-30 percent, perpendicular to both albite twinning and basal cleavage give anorthite contents that appear to be distributed evenly from An23 to A55; complex zones and intergrowths common; groundmass microlites may group around An17 but cannot be determined accurately; two-fluid inclusions from 0.004-0.02 mm in diameter occupy negative crystals in certain zones of the feldspar. Stubby euhedral hypersthene, 5-10 percent, is pleochroic in light pink and light green. Accessories are clinopyroxene, 1 percent; magnetite, 2 percent; oxyhornblende, 1 percent; and tridymite, 1 percent. Fluidal groundmass glass has N=1.504(?).	Snyder_1959_10	Lava			Whole-rock	64.91	0.53	16.29	4.73	0.13	1.98	5.08	4.14	1.71	0.15	99.91	424	NN	1.72	3.17	H2OM=0.03; H2OP=0.31; CO2=0	NN		33.8		296																												6.1							units are percent 1.42	745	XRF: Rb, Sr, Ni; NN: K;

SAMPLE LOCATION

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