Filling up the shelf — A sedimentary response to the last post-glacial sea rise

Abstract

Following the Last Glacial Maximum (LGM) lowstand, global sea-level rose by ~ 120 m flooding previously exposed continental shelves worldwide with water and sediments. In these drowned environments sediment accumulation patterns are dictated by a superposition of vertical tectonic motion, sea-level change and sediment supply rates, which are hard to distinguish from one another. This study focuses on a unique region where the first two components are known and well constrained, the terminal part of the Nile littoral cell along the eastern Mediterranean continental margin. Data analysis is based on detailed interpretation of four newly obtained high-resolution seismic reflection surveys integrated with two industrial seismic surveys. The age of sedimentary sequences is constrained by correlation with drillholes, while accumulation patterns strongly correlate with the local model-based sea-level curve. Our sub-meter resolution seismic stratigraphy reveals post LGM shoreline migration and suggests a seismic based sea-level curve. Since data presented here provide the first direct insight into the sedimentary accumulation pattern, they are used to calibrate the modeled curve. This simple, yet innovative approach, stresses the importance of high resolution seismic reflection data to sea-level research worldwide while serving as a reference for the entire Mediterranean Sea.