Harald Furnes, Ingvar Birgir Fridleifsson; Tidal Effects on the Formation of Pillow Lava/Hyaloclastite Deltas. Geology ; 2 (8): 381–384. doi: https://doi.org/10.1130/0091-7613(1974)2<381:TEOTFO>2.0.CO;2
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A shallow marine volcanic delta in Iceland shows the contact between pillow lava/hyaloclastite and a capping subaerial lava flow. Across the strike of the foreset beds of the delta, this contact shows altitude variations of the order of 2 to 3 m. These variations are considered to result from high- and low-tide fluctuations in sea level during construction of the delta. These structures are of use in distinguishing between marine and non-marine volcanic deltas, to indicate tidal range, and to provide information about flow rate of the lava and, hence, a minimum time for the formation of pillow lava/hyaloclastite deltas.