Table T4. Lobe structures: terminology, definitions, and abbreviations.

Distinct cg Contact featuring clearly separated glassy pahoehoe surfaces
Annealed, fused ca Contact between lobes is marked by a centimeter-thick glassy band formed by fusion of the original lobe surfaces
Discontinuous cd Contact between lobes dissipates or disappears when followed in outcrop
Vesiculation structure:
Vesicles ve Molds of gas-filled voids frozen in the lava and are referred to as microscopic (<2 mm diameter) or macroscopic (>2 mm diameter)
Diktytaxitic texture vd Microscopic (<2.0 mm), irregular intercrystalline voids and outlined by crystal faces of adjacent groundmass minerals (Fuller, 1931)
Segregation vesicle sv Vesicles lined by segregated material
Pipe vesicles andvesicle cylinders pvvc Roughly cylindrical pipes of near-vertical orientation that are hollow (pv) or filled with vesicular segregated material (vc)
Horizontal vesicle sheets hvs Sheets of vesicular segregated material, centimeters to tens of centimeters thick, that are continuous (>50 m long) and discontinuous (1-10 m long) on an outcrop scale; these sheets were previously identified as segregation veins or vesicle sheets (e.g. Goff, 1996)
Megavesicles mv Dome-shaped voids with flat floors and arched to dome-shaped roofs; their dimensions range from several to tens of centimeters; they are floored by moderately vesicular to nonvesicular segregated material and occur in close association with horizontal vesicle sheets
Vesicular zone hvz Decimeter- to meters-thick horizons with high concentrations (>10 vol%) of macroscopic vesicles
Petrographic texture:
Crystallinity c, hc, hyh, G Relative abundance of crystals vs. glassy mesostasis is indicated by holocrystalline (c [crystallinity = 90%-100%]), hypocrystalline (hc [50%-90%]), hypohyaline (hyh [10%-50%]), or holohyaline (G [0%-10%])
Crystal size of the lava groundmass (See Table T5)