Regional stratigraphic framework linking continental shelf and coastal sedimentary deposits of west-central Florida Stanley D. Locker a; Ã , Albert C. Hine a , Gregg R. Brooks b a College of Marine Science, University of South Florida, St. Petersburg, FL 33701, USA b Department of Marine Science, Eckerd College, St. Petersburg, FL, USA Accepted 1 June 2003 Abstract AregionalstudyoftheHolocenesequenceonlappingthewest-centralFloridaPlatformwasundertakentomerge our understanding of the barrier-island system with that of the depositional history of the adjacent inner continental shelf. Key objectives were to better understand the sedimentary processes, sediment accumulation patterns, and the history of coastal evolution during the post-glacial sea-level rise. In the subsurface, deformed limestone bedrock is attributed to mid-Cenozoic karstic processes. This stratigraphic interval is truncated by an erosional surface, commonly exposed, that regionally forms the base of the Holocene section. The Holocene section is thin and discontinuous and, north or south of the Tampa Bay area, is dominated by low-relief sand-ridge morphologies. Depositionalgeometriestendtobemoresheet-likenearshore,andmoundedorridge-likeoffshore.Sandridgesexhibit 0.5^4mofrelief,withridgewidthsontheorderof1kmandridgespacingofafewkilometers.Thecentralportionof the study area is dominated nearshore by a contiguous sand sheet associated with the Tampa Bay ebb-tidal delta. Sedimentary facies in this system consist mostly of redistributed siliciclastics, local carbonate production, and residual sediments derived from erosion of older strata. Hardground exposures are common throughout the study area. Regional trends in Holocene sediment thickness patterns are strongly correlated to antecedent topographic control. Both the present barrier-island system and thicker sediment accumulations offshore correlate with steeper slope gradients of the basal Holocene transgressive surface. Proposed models for coastal evolution during the Holocene transgression suggest a spatial and temporal combination of back-stepping barrier-island systems combined with open-marine, low-energy coastal environments. The present distribution of sand resources reflects the reworking of these earlier deposits by the late Holocene inner-shelf hydraulic regime. ß 2003 Elsevier B.V. All rights reserved. Keywords: west Florida shelf; Holocene stratigraphy; barrier island; sand ridge 1. Introduction An investigation of the inner continental shelf o¡ west-central Florida was conducted for the 0025-3227/03/$ ^ see front matter ß 2003 Elsevier B.V. All rights reserved. doi:10.1016/S0025-3227(03)00191-9 * Corresponding author. Tel.: +1-727-553-1502; Fax: +1-727-553-1189. E-mail address: slocker@marine.usf.edu (S.D. Locker). MARGO 3359 25-8-03 Cyaan Magenta Geel Zwart Marine Geology 200 (2003) 351^378 R Available online at www.sciencedirect.com www.elsevier.com/locate/margeo