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SAMPLE INFO : unnamed2

Sample ID:	unnamed2
Station ID:	unnamed2
Latitude:	62.00572
Longitude:	-144.01935
Datum:	NAD83
Date Sampled:	1902-01-01
Sample Type 1:	Lava

Text Description:
On the southern slope of Mount Wrangell, near the head of Cheshnina Glacier, at an elevation of between 7,500 and 8,000 feet above tide, is a vesicular augite-bearing hypersthene-andesite, which is presumably a recent flow. In the hand specimen the rock is seen to be very porous, with abundant square and lath-shaped feldspar sections of all sizes up to 5 mm in diameter imbedded in a jet-black glassy base. Under the microscope the larger plagioclase phenocrysts prove to be basic labradorite, Ab3An4 usually. One test gave the more acidic variety, and the presence of one or two zoned sections indicates some range in species. From the largest phenocrysts there is a gradation in size to laths too small for determination. The hypersthene is very subordinate to the feldspar in amount, and occurs usually in grains and imperfect crystals. Only one or two fragments of augite were observed. The groundmass is an opaque brown glass containing an abundance of minute crystals.

References:

Geology of the central Copper River region, 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
unnamed2	62.00572	-144.01935	Mendenhall, W. C.	1902-01-01		Wrangell		On the southern slope of Mount Wrangell, near the head of Cheshnina Glacier, at an elevation of between 7,500 and 8,000 feet above tide.	On the southern slope of Mount Wrangell, near the head of Cheshnina Glacier, at an elevation of between 7,500 and 8,000 feet above tide, is a vesicular augite-bearing hypersthene-andesite, which is presumably a recent flow. In the hand specimen the rock is seen to be very porous, with abundant square and lath-shaped feldspar sections of all sizes up to 5 mm in diameter imbedded in a jet-black glassy base. Under the microscope the larger plagioclase phenocrysts prove to be basic labradorite, Ab3An4 usually. One test gave the more acidic variety, and the presence of one or two zoned sections indicates some range in species. From the largest phenocrysts there is a gradation in size to laths too small for determination. The hypersthene is very subordinate to the feldspar in amount, and occurs usually in grains and imperfect crystals. Only one or two fragments of augite were observed. The groundmass is an opaque brown glass containing an abundance of minute crystals.	unnamed2	Lava			Whole-rock	61.19	0.73	16.7	5.27	0.14	3.43	6.1	4.04	1.58		100.29	1993	NN	1.3	4.08	H2O=0.22; H2OP=0.36; CO2=0	NN																																								1993

SAMPLE LOCATION

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