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).
| 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 | 2 | 0 | 2 | 0 | 0 | 0 | 0 | 0 | 6 | 0 | 0 | vitric, microlitic |
| Min | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 6 | 0 | 0 | Marianas |
| Slide | Site | Possible Origin | Cal. | Quartz | Feldspar | Pyroxene | Amphibole | Opaques | Olivine | Biotite | Muscovite | Epidote | Garnet/ Spinel | Ig./Met. Rocks | Sed. Rocks | Grog | Lithics |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| WD_7_1 | Waterfront Annex (Guam) | Guam | 0 | 0 | 1 | 2 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 6 | 0 | 0 | vitric, microlitic |
| WD_7_24 | Ipan Beach (Guam) | Guam | 0 | 0 | 2 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 6 | 0 | 0 | vitric |
| WD_7_3 | Ordnance Annex (Guam) | Guam | 0 | 0 | 2 | 1 | 0 | 2 | 0 | 0 | 0 | 0 | 0 | 6 | 0 | 0 | vitric, microlitic |
| WD_8_1 | Mochong (Rota) | Guam | 0 | 0 | 2 | 1 | 0 | 2 | 0 | 0 | 0 | 0 | 0 | 6 | 0 | 0 | vitric |
| WD_8_9 | Tarague (Guam) | Guam | 0 | 0 | 2 | 1 | 0 | 2 | 0 | 0 | 0 | 0 | 0 | 6 | 0 | 0 | microlitic, vitric |
Highly lithic sand temper.
Andesitic temper sand rich in glassy volcanic rock fragments and lacking any calcareous grains indicative of coastal origin.
Highly lithic sand temper.
Deeply weathered. Volcanic sand temper.
Poorly sorted volcanic sand temper rich in glassy volcanic rock fragments characteristic of indigenous Guam tempers.