ABSTRACT: Based on the stratigraphic distribution of planktonic microfossils (mostly planktonic foraminifera) and abundance patterns of benthic foraminifera we determine the temporal completeness of one land section and three wells through the Lower andMiddle Miocene Carapita Formation of eastern Venezuela, compare the extent of the hiatuses in the sections and document changes in paleodepth at these localities during the early and Middle Miocene. We determine that changes in paleodepth are associated with hiatuses, but see no relationshipwith the global changes in sea-level inferred from deep sea isotope records. This strongly suggests that there was a strong tectonic forcing on stratigraphic architecture at upper and middle bathyal depths, as to be expected in a tectonically active area. However, similar stratigraphic patterns are also observed elsewhere, implying that a widespread tectonic structuring of the stratigraphic architecturemay have been operative. Recognition of hiatuses (not merely unconformities) as primary stratigraphic components will make possible an uninterrupted documentation of sequences boundaries from subaerial to bathyal environments, and help determine objectively the structural mechanism(s) operating on the genesis of stratigraphic sequences (sensu Catuneanu et al. 2009). Biostratigraphy (and biochronology) are the main tools to understanding this structuring.

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