The first dive by ROPOS at the Flow site in August 1993 crossed over a largely sediment-free, glassy lava flow lying about 700 m east of the 1993 flow (Figures 5, 6, and 7). Subsequent comparison of SeaBeam surveys clearly showed that this lava was erupted between 1982 and 1991 [Chadwick et al., 1995]. This older flow appears to be morphologically similar to the 1993 flow, consisting of mostly pillow lavas (Plate 2f) but with a distinct zone of flattened and partially drained-out pillow flows along the crest of the mound. The crest of the 1982–1991 lava flow has a veneer of dull yellow Fe-Si sediment (Plate 2g), which is likely the Fe-Si precipitates observed forming during the cooling phase of the 1993 lava flow (Plate 2c). Similar precipitates were also found on the crest of the lava mounds on the northern Cleft segment that erupted in the mid-1980s [Chadwick and Embley, 1994], so the presence of these deposits is now a well-documented indicator of the cooling phase of recent pillow lavas and their feeder dikes. The northern extent of this flow is currently unknown due to lack of near-bottom photographic coverage. The separation between this eruptive mound and the 1993 mound is ~800 m (centerline to centerline).
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