Controls on grain-size patterns in periplatform carbonates: Marginal setting versus glacio-eustacy

The results show that the grain-size patterns of both margins are controlled by late Neogene sea-level fluctuations. The accretionary leeward margin sediments indicate the same grain-size pattern as previously described in the literature. However, the erosional windward margin shows a reverse pattern, with coarser sediments in interglacials and finer deposits in glacials. This proposes that the leeward margin grain-size pattern is controlled by the productivity-export mode of the platform. This is indicated by the platform-top-derived fine muds, transported off-bank, to form a thick sediment wedge on the low-angled slope during interglacials. In contrast, on the windward margin, the sediment flux pattern is controlled by the impact of mass transport processes. This is indicated by the increased occurrence of turbidites during interglacials that might be more frequent at this time because the steep-angled erosional slope is less apt for the deposition of excess fine material. This material is eroded and/or bypasses the slopes and is redeposited in the periplatform basin setting.