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K/T tsunami ref



Impacts, Tsunamis, and the Haitian Cretaceous-Tertiary Boundary Layer,
Florentin J-M. R. Maurrasse and Bautam Sen. Science, v252, 21-Jun-1991

The marker bed at the Cretaceous-Tertiary boundary of the Beloc Formation
(southern Haiti) contains abundant coarse-grained microtektites and minor
amounts of shocked quartz grains in the basal part. The upper part is 
composed of medium-grained marl with amalgamated microtektite lenses and
finer grained marl lenses disseminated throughout. Field and petrographic
observations, and the distribution of planktonic foraminifera suggest
that the bed formed from a complex sequence of events. A bolide impact
nearby produced microtektites that settled to form a nearly pure layer
at the base. Vaporized materials with anomously high extraterrestrial
components settled last, along with carbonate sediments. The entire bed
became sparsely consolidated. Subsequently, another major disruptive
event, perhaps a giant tsunami, partly reworked the initial deposit.
Cohesive fragments of the original marker bed mixed with exotic materials
were redeposited as lenticular bodies. The process also may have caused
further mixing of Cretaceous and Tertiary microfossils, as observed at
Beloc and elsewhere.