Figure 2.
(A) Temporal evolution of Sr (compatible element) and Nb (incompatible element) as a function of eruption age in the Central Plateau Member lavas (X-ray fluorescence data on whole rock; Girard and Stix, 2010); ppm—parts per million. (B) Cathodoluminescence photomicrographs of two Central Plateau Member quartz grains (top: Buffalo Lake lava flow, 160 ka; bottom: West Yellowstone lava flow, 110 ka) exhibiting dark rims and bright cores, rounded cores, and subrounded to rounded rims. Yellow circles are Ti analyses (ppm) by laser-ablation ICP-MS. (C) Ti in Central Plateau Member quartz crystals as a function of eruption age. (D) Average Ti content of quartz rims and unzoned quartz crystals as a function of Ti in glass (electron microprobe analyses; Girard and Stix, 2010). (E) Photomicrograph of glass embayments in a Central Plateau Member quartz crystal (Moose Falls lava flow, 80 ka).