Site: Ipan Beach

Island: Guam       Lithology: Composite high island ( Nunn et al. (2016) )

Lithology: Limestone ( Dickinson (2006) )

Lithology and Age: Cenozoic sedimentary rocks ( Chorlton (2007) )       Macrostrat Geological Map Link

Near/In Geonames ID: 4038813       Wikidata ID: Q16938476       Getty Thesaurus of Geographic Names ID: None

Mindat Loc ID: None


In:

Guam Island Wikidata ID: Q16635

Mariana Islands Wikidata ID: Q153732

Note that to see the 'Geology' layer (layer options in top right corner) you may have to zoom out.


Fabrics:

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
tpr21 0 0 2 2 0 2 0 0 0 0 0 6 0 0 vitric, microlitic
Guam lithic hi andesitic 0 0 1 1 0 1 0 0 0 0 0 6 0 0 Marianas

Slides:

Slide Fabric Possible OriginWareCal. QuartzFeldspar Pyroxene Amphibole Opaques OlivineBiotite Muscovite Epidote Garnet/ Spinel Ig./Met. Rocks Sed. Rocks Grog Lithics
WD_7_24 tpr21 (Guam lithic hi andesitic) Guam Latte plainware (1000 - 429 BP) 0 0 2 1 0 1 0 0 0 0 0 6 0 0 vitric

WD_7_24

guam_IPA1 guam_IPA1
Sherd IPA1 from Ipan Beach (Guam). Slide WD_7_24 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.

Andesitic temper sand rich in glassy volcanic rock fragments and lacking any calcareous grains indicative of coastal origin.


References:

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

204 Guam, Mariana, 2001 (Dickinson, W.)