HAWAI‘I ROCKS (and minerals)
description
Transcript of HAWAI‘I ROCKS (and minerals)
HAWAI‘I ROCKS
(and minerals)
Oceanite (from Mauna Loa) – a basalt with >40% mafic phenocrysts, and all thephenocrysts are olivine.
olivine
Ankaramite (from Hualālai) – a basalt with >40% mafic phenocrysts, and those phenocrysts consist of olivine and pyroxene
olivine
pyroxene
Pyroxene crystals, weathered out of ankaramite lavas, East Maui SW rift zone
Outer, weathered surface of ankaramite from Rarotonga, Cook Islands
pyroxene
Freshly broken surface of ankaramite from Rarotonga, Cook Islands
pyroxene
olivine
amygdule(former vesicle, nowfilled with some sortof secondary mineral)
Vesicular basalt (from Kohala) with lots of little clusters of plagioclase feldspar phenocrysts (and a few olivine phenocrysts).
plagioclase feldspar
olivine
vesicle(frozen bubble)
Very fine-grained (almost glassy) basalt, from Wai‘anae
http://www.youtube.com/watch?v=fSPzMva9_CE
http://www.youtube.com/watch?v=lISK1YFcZBM
VIDEOS OF SUPER-COOLED WATER
Gabbro (from Wailau, Moloka‘i)plagioclase feldsparpyroxene
Granite (from Mojave desert, California)plagioclase feldspar
quartzpotassium feldspar
biotite, or maybe hornblende
Obsidian, from near Mono Lake, California
Pumice from Pu‘u Wa‘awa‘a, Hualālai
Calcareous sandstone (from near Ko Olina, O‘ahu)
Fragment of pāhoehoe lava showing the rapidly-chilled (and therefore glassy) outersurface, and the more slowly-cooled (and therefore crystalline) interior