Tsunamis in a stormy sea: Middle Cambrian inner shelf limestones of western Argentina

PRATT, BRIAN.R Y BORDONARO, OSVALDO L.

JOURNAL OF SEDIMENTARY RESEARCH

Society for Sedimentary Geology

Lugar: Londres; Año: 2007 vol. 77 p. 256 - 262

1073-130X

Coarse-grained strata deposit on continental shelves and epeiric seas in some tens of meters water depht are conventionally ascribed to storms . Portions of Middle Cambrian La Laja Fm of the Argentine Precordillera formed in such a submerged epeiric platform or shelf. They comprise a suite of three limestone facies: argillaceous burrowed mudstones, bioclastic grainstone and intraclastic conglomerate conposed of pieces of mudstoneincluding cemented haloes around burrows. Because they are abruptly interbeded and encased within uniform mudstone. and there are no stratigraphic patterns, allochthonous material. or unconformities to indicate sea level fluctuation, the events that created the conglomerates were more likely tsunamis not storms.