Hjarnø Sund: An Eroding Mesolithic Site and the Tale of two Paddles

Bone biodeterioration—The effect of marine and terrestrial depositional environments on early diagenesis and bone bacterial community

“…The baked bone fragment from the submerged gyttja environment in which we observe tunneling could have been exposed, or partly exposed, in the water column, potentially making it available for attack by organisms favouring higher oxygen or light levels. This assumption is supported by the aforementioned observations that the whole area is under erosion [ 53 ] and thus exposure of the bones during the experimental period is not implausible. This highlights the potential damage cultural heritage artifacts may experience if exposed to the light, oxygenated seawater and the bacteria herein.…”

“…Regarding the difference between the two submerged environments the gyttja environment is a well-known archaeological site [ 51 , 52 ], where the archaeology is preserved in the organic gyttja layers. The site is known to be under erosion [ 53 ] and the gyttja layers are relatively thin. The bone fragments were buried where only the upper 18 cm were very organic, below which the gyttja content decreased ( S3 Fig ).…”

Underwater archaeology and submerged landscapes in western Australia

“…A second step is the analysis of the underwater archaeological shell midden of Hjarnø in Denmark, one of the few such middens known to exist anywhere in the world. Previous excavation established this to be a midden of the classic Ertebølle culture (approximately 8000 years old), associated with gjytta (peat deposits), a hearth area enclosed within the shell remains, flint and antler artefacts, food remains (including bones of fish, land mammals and marine mollusc shells), and wooden artefacts, including remains of a log boat and decorated wooden paddles ( Figure 5) (Skriver et al 2017). The objective at Hjarnø is to combine coring and new excavation of the submerged archaeological deposits…”

Underwater Shell Middens: Excavation and Remote Sensing of a Submerged Mesolithic site at Hjarnø, Denmark

“…Initial investigations at the site in 2009 focused on the lagoon (gyttja) deposits. A range of well-preserved organic artefacts were recovered including painted paddles, dugout canoes, axes, bows, and fishing implements (Skriver et al 2017(Skriver et al , 2018. Through continued fieldwork, it was possible to define the horizontal and vertical extent of the site through auger survey, which demonstrated that the gyttja deposits served to protect the stratified shell deposits (Figure 2).…”