Isolated carbonate platforms are dominated by carbonate buildups and surrounded by water at great depths. They are gentle and circumscribed by transitional zones from steep scarps (or slopes) to deep sea (or lakes). The Bahamas Platform in the Caribbean Sea is a typical example of isolated carbonate platforms composed of modern sediments
[1⇓-3]. Isolated carbonate platforms were surrounded by source rocks during their formation and would then be buried at great depths for a long period. For these reasons, they can easily develop into large and integrated reef-shoal reservoirs and thus have attracted more attention for oil and gas exploration. Since 2006, 14 large oil fields, including Lula, Buzios and Aram fields, have been discovered in deep-water pre-salt carbonates in passive continental marginal basin of the Santos Basin in Brazil. In these oilfields, the average recoverable reserves are 2.13×10
8 t for a field. The recoverable reserves in Buzios Field, the largest one, amount to 14.3×10
8 t. And the commercial exploration success rate is higher than 40%
[4], indicating that deep-water carbonate platforms in passive continental marginal basins have great prospects for oil and gas exploration. In other deep-water passive marginal basins around which major oil and gas discoveries have been made, such as the Gulf of Mexico Basin, the Guyana Basin, the Lower Congo Basin, and the Rovuma Basin, hydrocarbon is mainly concentrated in the deep-water gravity-flow clastic depositional systems formed in the late drift and depression stage. Because these basins have been highly explored, where many oil and gas fields have been discovered, their geological conditions and hydrocarbon accumulation patterns have been clearly described
[5⇓⇓⇓-9]. The pre-salt carbonate platforms in the Santos Basin were formed in the early intra-continental and inter-continental rifting stages. Affected by the low extent of exploration and the limited amount of available data in deep-water pre-salt sediments, previous studies on the Santos Basin were focused primarily on the regional geology
[6⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓-23] and a small number of discoveries
[4-5], the geological setting for the formation of deep-water pre-salt isolated carbonate platforms in the basin, sedimentary build-ups and distribution patterns of these platforms, and the main factors controlling the formation of large oilfields have not been adequately studied, so the future targets for oil and gas exploration in the basin still remain unclear. Based on available 2D/3D seismic, core and drilling data, this paper analyzes the superposition and evolution processes of the Santos Basin’s prototypes and the characteristics of sedimentary fillings in these prototype basins, reveals the geological setting for the formation of pre-salt carbonate platforms, establishes the sedimentary build-up models and describes the seismic response of two types of isolated carbon platforms, identifies the main factors controlling the formation of large pre-salt carbonate reservoirs through the dissection of large oilfields discovered in the pre-salt play. It also predicts the favorable zones of hydrocarbon accumulation based on seismic facies, and finally proposes the favorable zones and targets for future exploration to provide reference for the strategic selection of exploration blocks/zones, the evaluation of new exploration projects, and arrangement of exploration wells in passive margin basins.