Fabric Code: tpr12

Saipan vitric

Glass-rich volcanic sands, quartz-free, derived from either aphyric dacite or felsic andesite. Tan to brown vesicular glass. Feldspar is plagioclase. Clinopyroxene and orthopyroxene present.

Fabric Class:

Vitric: Dominated by vitric lithic inclusions.

Andesitic Arc: Dominated by andesite and basalt lithic fragments, with microlitic, felsitic and vitric textures, and the andesite minerals (plagioclase, clinopyroxene and sometimes hornblende).

Sites:

Mineral and Rock Abundances

None (0)	Minor (1)	Few (2)	Common (3)	Frequent (4)	Major (5)	Very Dominant (6)
0%	0-5%	5-15%	15-30 %	30-50%	50-70%	70-100%

Name	Cal.	Quartz	Feldspar	Pyroxene	Amphibole	Opaques	Olivine	Biotite	Muscovite	Epidote	Garnet/ Spinel	Ig./Met. Rocks	Sed. Rocks	Grog	Lithics/ Region
Max	0	0	2	1	0	0	0	0	0	0	0	6	0	0	vitric, felsitic
Min	0	0	2	1	0	0	0	0	0	0	0	6	0	0	Marianas

Representative slides:

Slide	Site	Possible Origin	Cal.	Quartz	Feldspar	Pyroxene	Amphibole	Opaques	Olivine	Biotite	Muscovite	Epidote	Garnet/ Spinel	Ig./Met. Rocks	Sed. Rocks	Grog	Lithics
WD_4_16	Taga (Tinian)	Saipan	0	0	2	1	0	2	0	0	0	0	0	6	0	0	vitric, felsitic
WD_4_17	Taga (Tinian)	Saipan	0	0	2	1	0	0	0	0	0	0	0	6	0	0	vitric, felsitic

WD_4_16

Glass-rich volcanic sand , Type C, tan to brown vesicular glass. Marianas cordmarked sherd. Clinopyroxene and orthopyroxene.

WD_4_17

Glass-rich volcanic sand , Type C, Marianas incised sherd. Clinopyroxene dominant, and orthopyroxene.

References:

323 Mariana, reports 1-15 for MTAT, 1998 (Dickinson, W.)