Subaqueous lava flow lobes, observed on ROV dives off Hawaii
Remotely operated vehicle (ROV) KAIKO dives north of Oahu Island, Hawaii, and on the lower south rift zone of Loihi Seamount revealed diverse flow morphologies of submarine lava that correlate with slope and rate of lava delivery. Steep to moderate (>10°) slopes are covered with elongate pillows and narrow pahoehoe streams; bulbous pillows and smooth pahoehoe lobes occur on flat areas and gentle slopes. Some gentle slopes are covered by lobate sheet flows that supply pillow flows. Smooth pahoehoe lobes change upslope into lobate sheets, indicating that the sheets form by coalescence and inflation of successively emplaced flow lobes. Many pahoehoe flows contain hollow, tumuli-like lobes that have inflated and collapsed. Thin crusts (4-20 cm) and large volumes (0.7-1050 m 3 ) of such inflated lobes suggest lava supply rates of 0.01-8 m 3 /min. These calculated supply rates are more than one order of magnitude larger than those for subaerial tumuli in Iceland. Thinner viscoelastic layers of subaqueous lobes at the time of inflation allowed higher excess pressures and expansion rates.
Citation Information
Publication Year | 2000 |
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Title | Subaqueous lava flow lobes, observed on ROV dives off Hawaii |
DOI | 10.1130/0091-7613(2000)28<503:SLFLOO>2.0.CO;2 |
Authors | Susumu Umino, Peter W. Lipman, Sumie Obata |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Geology |
Index ID | 70205934 |
Record Source | USGS Publications Warehouse |