Fig. 1
From: Compositional boundary layers trigger liquid unmixing in a basaltic crystal mush
Compositional boundary layer morphology in BSE images from samples of the 1976 Kīlauea Iki lava lake. a–d The changing morphology of immiscible liquids in the 1976 drill core from the Kīlauea Iki lava lake, viewed in BSE images. a Plagioclase lath (Pl) surrounded by an Fe-rich compositional boundary layer sampled at 45.4 m depth in the crust (quench temperature of 1112 °C). b A thinner compositional boundary layer surrounding plagioclase (quench temperature of 1073 °C) and the nanoemulsion is coarser. c At 43.7 m depth (quench temperature of 1054 °C), the compositional boundary layer surrounding plagioclase is discontinuous and sub-micrometre thick. Note the presence of darker (more Si-rich) glass immediately surrounding pyroxene (Cpx) grains. The bulk of the glass comprises a nanoemulsion. d Isolated and attached Fe-rich droplets in interstitial glass at 42.8 m depth (quench temperature 1017 °C). Note the Fe-rich liquid wets the pyroxene with a low wetting angle. e, f Compositional boundary layers surrounding plagioclase from Snake River Plain tholeiites. The calculated natural quench temperature of this sample is 1096 °C. Note the oxide dendrites within the compositional boundary layer and partially embedded in the plagioclase
