| The Paleocene Guasare Formation, Maracaibo Basin, Venezuela, represents a mixed carbonate-terrigenous clastic succession. Ten lithofacies were defined. Lithofacies can be grouped into three lithofacies successions representing coastal plain, off-shore and near-shore, tide and storm influenced settings. Recognition of encrusted shells, micrite envelopes, borings in skeletal fragments, flower spar, dissolution cavities, calcitization and equant spar in pelecypod beds indicate textural and compositional changes related to diagenetic processes in the marine, vadose and phreatic meteoric realms. Such limestones probably represent cheniers formed during periods of reduced sediment influx and reworking by waves. Environmental reconstruction indicates that sedimentation of the Guasare Formation occurred in a dynamic delta setting with tidal influence where delta lobe progradation, abandonment, transgression and renewed progradation were the dominant controlling factors on sedimentation. The repeated development of similar lithofacies successions due to switching delta lobes indicates that deposition of the Guasare Formation was basically controlled by autocyclic processes. |
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