Fabric Code: tpr18

Guam hybrid

Hybrid (calcareous-terrigenous) tempers composed of mixed calcareous and pyroxene-rich placer sand, or andesitic sand that is lithic-rich.

Fabric Class:

Pyroxenic Calcareous: Dominated by pyroxene inclusions, with calcareous.

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	4	0	2	5	0	2	0	0	0	0	0	3	0	0	vitric, felsitic
Min	2	0	1	3	0	1	0	0	0	0	0	2	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_5_14	Nomna Bay (Guam)	Guam	4	0	2	4	0	2	0	0	0	0	0	2	0	0	felsitic, vitric
WD_5_7	Nomna Bay (Guam)	Guam	4	0	2	3	0	2	0	0	0	0	0	2	0	0	felsitic, vitric
WD_8_12	Tarague (Guam)	Guam	2	0	1	5	0	1	0	0	0	0	0	2	0	0	vitric, microlitic

WD_5_14

Nomna-8 has a full slide scan available. Imaged by K. Hardy and M. Leclerc, ANU.

Hybrid lithic.

WD_5_7

Ma_GU_23_2 — Sherd Ma-GU-23-2 from Nomna Bay (Guam). Slide WD_5_7 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.

Ma_GU_23_2 — Sherd Ma-GU-23-2 from Nomna Bay (Guam). Slide WD_5_7 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 calcareous temper.

WD_8_12

Tarague_71_5 — Sherd 71-5 from Tarague (Guam). Slide WD_8_12 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.

Tarague_71_5 — Sherd 71-5 from Tarague (Guam). Slide WD_8_12 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.

Hybrid beach sand temper in which calcareous reef detritus is admixed with terrigenous grains derived from volcanic rocks.

References:

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