Inter Granular Basalt

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Intergranular basalt

ophitik

subopitik

pokilitik

FIG. 5. Microphotographs: a. Subophitic texture in the lowermost flow (AD96-30) of the Morro Negro basaltic sequence; notice that clinopyroxenes have a pinkish color, olivine microphenocryst are partly altered to brownish clay minerals, and Fe-Ti oxides are abundant; b. Glomeroporphyritic assemblage of plagioclase and olivine with iddingsite rim in the Morro Negro mesa basalt (AD96-27); c. Olivine phenocrysts altered to brown phyllosilicates and rimmed by orthopyroxene, in the prismatic dacitic lava flow (AD96-15); d. Typical assemblage of El Toro Formation dacite (AD96-15): sieve-textured plagioclases, clinopyroxene, and orthopyroxene (grey colored) rimmed by clinopyroxene (orange); phenocrysts are set in a glassy matrix.

Intergranular texture in massive fine-grained basalt (cross-polarized light; field of view = 5.0 mm) (Sample 309-1256D-86R-3, 94–97 cm).

Gabro alkali

Teprite

Fonolit nefelitownit

Ryodasit

Ryolit

Syenit

Diorit

Granit

Granodiorit

Monzonit

Norit

Peridotit

Syenit

troktolit

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