Fabric Code: tpr6

Marianas andesitic

Non-quartzose volcanic sand tempers of andesitic character. Feldspar is plagioclase. Clinopyroxene and orthopyroxene present.

Fabric Class:

Igneous Feldspathic: Dominated by igneous lithic inclusions with feldspars.

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. QuartzFeldspar Pyroxene Amphibole Opaques OlivineBiotite Muscovite Epidote Garnet/ SpinelIg./Met. Rocks Sed. Rocks Grog Lithics/ Region
Max 0 1 5 2 0 2 0 0 0 0 0 4 0 0 microlitic, felsitic, vitric
Min 0 0 4 1 0 2 0 0 0 0 0 3 0 0 Marianas

Representative slides:

Slide Site Possible OriginCal. QuartzFeldspar Pyroxene Amphibole Opaques OlivineBiotite Muscovite Epidote Garnet/ Spinel Ig./Met. Rocks Sed. Rocks Grog Lithics
WD_4_1 Sabanan Fiang (Saipan) Saipan 0 1 5 1 0 2 0 0 0 0 0 4 0 0 microlitic, felsitic, vitric
WD_5_1 Rota (Nec) (Rota) Marianas 0 0 5 2 0 2 0 0 0 0 0 3 0 0 microlitic, felsitic, vitric
WD_5_3 Mochong (Rota) Marianas 0 0 4 2 0 1 0 0 0 0 0 4 0 0 vitric, microlitic, felsitic
WD_5_4 Asmatmos (Rota) Marianas 0 0 5 2 0 1 0 0 0 0 0 3 0 0 microlitic, felsitic, vitric

WD_4_1

SabananFiang98_4 SabananFiang98_4
Sherd 98-4 from Sabanan Fiang (Saipan). Slide WD_4_1 from Dickinson Collection, Bishop Museum. x4 Magnification PPL (left) XPL (right). Scale bar: 0.5mm. High resolution image (user: Guest pwd: Guest) or full slide in VIMIPO. Imaged by K. Hardy and M. Leclerc, ANU.

Quartz-poor volcanic sand temper of feldspathic composition and andesitic character. Latte. Clinopyroxene and orthopyroxene.


WD_5_1

Rota_R_23 Rota_R_23
Sherd Rota-R-23 from Rota (NEC) (Rota). Slide WD_5_1 from Dickinson Collection, Bishop Museum. x4 Magnification PPL (left) XPL (right). Scale bar: 0.5mm. High resolution image in VIMIPO (user: Guest pwd: Guest). Imaged by K. Hardy and M. Leclerc, ANU.

Poorly sorted, subangular to subrounded, andesitic volcanic sand temper rich in glassy volcanic rock fragments of tan to brown hues in thin section. Clinopyroxene dominant, but minor orthopyroxene.


WD_5_3

RotaII RotaII
Sherd RotaII from Mochong (Rota). Slide WD_5_3 from Dickinson Collection, Bishop Museum. x4 Magnification PPL (left) XPL (right). Scale bar: 0.5mm. High resolution image in VIMIPO (user: Guest pwd: Guest). Imaged by K. Hardy and M. Leclerc, ANU.

Marianas Plainware. Volcanic sand temper. Clinopyroxene dominant, but minor orthopyroxene.


WD_5_4

Asmatmos_FC2 Asmatmos_FC2
Sherd FC2 from Asmatmos (Rota). Slide WD_5_4 from Dickinson Collection, Bishop Museum. x4 Magnification PPL (left) XPL (right). Scale bar: 0.5mm. High resolution image in VIMIPO (user: Guest pwd: Guest). Imaged by K. Hardy and M. Leclerc, ANU.

Volcanic sand tempers of andesitic character. Latte sherd. Clinopyroxene dominant, but minor orthopyroxene.


References:

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