Impacts, Tsunamis, and the Haitian Cretaceous-Tertiary Boundary Layer

摘要: The marker bed at the Cretaceous-Tertiary boundary of Beloc Formation (southern Haiti) contains abundant coarse-grained microtektites and minor amounts shocked quartz grains in basal part. upper part is composed medium-grained marl with amalgamated microtektite lenses finer-grained disseminated throughout. Field petrographic observations, distribution planktonic foraminifera suggest that formed from a complex sequence events. A bolide impact nearby produced sett1led to form nearly pure layer base. Vaporized materials anomalously high extraterrestrial components settled last, along carbonate sediments. entire became sparsely consolidated. Subsequently, another major disruptive event, perhaps giant tsunami, partly reworked initial deposit. Cohesive fragments original mixed exotic were redeposited as lenticular bodies. This process also may have caused further mixing Cretaceous Tertiary microfossils, observed elsewhere.