Department of Geological Sciences, Brock University, St. Catherines, Ontario, Canada L2S 3A1.
Wave-induced liquefaction: a modern example from the Bay of Fundy
Article first published online: 14 JUN 2006
Volume 26, Issue 6, pages 835–844, December 1979
How to Cite
DALRYMPLE, R. W. (1979), Wave-induced liquefaction: a modern example from the Bay of Fundy. Sedimentology, 26: 835–844. doi: 10.1111/j.1365-3091.1979.tb00976.x
- Issue published online: 14 JUN 2006
- Article first published online: 14 JUN 2006
- (Manuscript received 16 AugustNovember 1978; revision received 6 March 1979)
Soft-sediment deformation features occur commonly on parts of intertidal sand bodies in Cobequid Bay, Bay of Fundy. These features are small- to intermediate-sized, slump-like bodies, 1-3 m2 in area and located on the crest and upper stoss side of ebb megaripples. External modification of these slumps indicates that they formed before complete emergence. The deformed cross-bedding within these bodies extends to a depth of 0.15-0.35 m and shows that deformation occurred during slumping and flowage of liquefied sand down the megaripple stoss side. Field evidence and calculations strongly indicate that this liquefaction results from the impact of 0.1-0.3 m high waves breaking against the megaripple lee faces. Neither rapid drawdown of the water level nor earthquake shocks are reasonable alternative explanations.
Indigenous wave activity provides an attractive substitute to tectonism as an explanation of soft-sediment deformation in ancient shallow-water sediments. Slow wave-induced compaction may also account for the relative scarcity of deformation structures in shallow marine sandstones.