| Summary: | A sequence stratigraphic and facies distribution model was developed by performing stratigraphic and lithofacies analyses of the Late Cretaceous volcano-sedimentary rock succession exposed at Cerro de Abra, north of the Bahía de Guánica. These rocks are part of the Parguera Limestone, specifically the lower and middle members, Bahía Fosforescente and Punta Papayo Members respectively. The stratigraphic section represents a geologic record from Santonian to Middle Campanian. The depositional sequence starts with deposition of the Bahía Fosforescente Member represented by a transgressive system tracts (TST) at the base and a highstand system tract (HST) during the Santonian, similar to the deposits of the Cotuí Limestone, north of the Lajas Valley. This is followed by a relative drop in sea level and up-dip volcanism that resulted in deposition of volcanic arenites with limestone intraclasts and planktonic foraminifera, and slumped blocks close to the base of the unconformity. These deposits are interpreted as result of a forced regression, and represents the start of deposition of the Punta Papayo Member of the Parguera Limestone during the Campanian. These deposits are interpreted to be stratigraphically equivalent to the Sabana Grande Formation north of the Lajas Valley. The deposits above the unconformity are interpreted to represent a forced regression, LST, TST, followed by a HST characterized by bedded, fine grained carbonates. This bedded fine-grained carbonates are equivalent to the Yauco Formation exposed north of the Lajas Valley. The models, based on lithology, fossil content and facies interpretation, integrated fieldwork and laboratory data that helped reconstruct the paleofacies and paleoenvironment of these members. This interpretation established a better stratigraphic correlation of the lower and middle members of the Parguera Limestone with the stratigraphy of the Cotuí Limestone, Sabana Grande Formation, Guaniquilla Limestone, and Yauco Formation exposed north of this area. Un modelo de ...
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