Recent Progress on the 3D Characterization of Submerged Flint Blades in a Sediment Environment

This study presents the progress work on the use of acoustic methods to detect and map submerged Stone Age sites. It presents the use of wave-propagation models to characterize submerged flint blades in a sediment environment. Two models are developed and demonstrated to be suitable for investigating submerged Stone Age objects. The first model is built around an analytical approach with considers simplified assumptions. The presence of flint specimens is defined thanks to an effective wave-number model that assumes a single scattering approach. The second model is based on a 3D time-domain Finite Element (FE) approach. This latter numerical model accounts for realistic 3D-scanned flint specimens and is shown to provide advanced understanding to the sediment environment response to an acoustic excitation. Both cases with and without the buried flint samples are simulated and the results obtained in the time and frequency domains are discussed in detail. Three parameters are also introduced and used to analyze the acoustic response. They are the instantaneous amplitude, instantaneous phase and instantaneous frequency initially developed for the composite materials. These parameters are used as an attempt to map the locations for the flint blade specimens. This work is a preliminary study for a project aiming at detecting, localizing and mapping submerged Stone Age sites. Some of these sites are known to contain important information about the early European Stone Age cultures.