Figure F16. Scanned core photographs and sketched interpretations of the bases of two highly olivine-augite-phyric basalt lava flows in the lower part of stratigraphic Unit III. A, B. Interval 330-U1376A-13R-4A, 16–99.5 cm: (A) photograph and (B) sketch of breccia-filled fissure in base of 33.1 m thick lava flow (lithologic Unit 15), baked zone in underlying hyaloclastite breccia (lithologic Unit 16), and chilled zone at base of flow. C, D. Interval 330-U1376A-14R-4A, 30.5–82.5 cm: (C) photograph shows base of 2.1 m thick flow that defines the bottom of stratigraphic Unit III, (D) sketch identifies a small fragment of aphyric basalt dike (lithologic Unit 18) at contact between lava flow (lithologic Unit 17) and underlying hyaloclastite breccia (lithologic Unit 19). Dotted lines in sketch of lithologic Unit 18 show trains of small vesicles. Note that these appear to be truncated upward at base of lithologic Unit 17 and downward at lower margin of lithologic Unit 18.
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