Text Description: |
Tuff horizon appears to be confined to the Mt. Gordon-East Cone area, and may have been extruded from the Ice Fields Plateau. It has been mapped as Mt. Gordon Basalt Flow, which is, coincidentally what the top of Jaeger Mesa has been mapped as. Yellow color is indicative of a phreatomagmatic eruption setting. Three morphologies have been identified and sampled: a) fine grained, finely laminated b) coarse inundated lapilli, and c) fine grained matrix with large pieces of scoria. Sample 16A is fine grained and finely laminated. Sample 16B is composed of indurated coarse yellow lapilli. No phenocrysts are visible in either sample. Sample 21 is a piece of the scoria. |