The area in northern Australia is now a wide estuary and floodplain, but at the end of the Ice Age and before that it was very different. The area has undergone tremendous changes: tens of thousands of years ago it was still 350 km of coastline, in the Holocene only 40 km, and the former semi-desert was replaced by marshes. These changes could also be vital for the first Australians to live here. The oldest archaeological site on the continent is located in this region, where traces of human presence can be found dating back at least 50,000 but up to 65,000 years.a few years after these discoveries They completely upset the experts and the public.
Area Map – The red circle indicates the location of the survey just taken.
Source: PLOS One
A survey was made of the area that used to provide a living place for people Flinders University It was carried out by its researchers using the latest geophysical tools and methods, so it was possible to reconstruct the former landscape in a non-invasive way. The search was done by Plus one It was described in a journal.
Surveys at a site called Red Lilly Lagoon revealed that not long ago the ocean reached this far, and about 8,000 years ago, a mangrove swamp dominated the area. These changes can also be traced in the petroglyphs of the area.
A kutatók az ERT, vagyis elektromos ellenállás tomográfia módszerével pillantottak be a talaj mélyére, és vizsgálták meg az ott egymásra rétegződött egykori üledékeket. A vizsgálathoz hosszabb vezetékkel összekötött elektródákat dugnak a talajba, majd áramot vezetnek be, és mérik az elektródák közti ellenállást. Az elektródák száma, elhelyezésének távolsága és mélysége befolyásolja, hogy milyen mélyen is lehet így a talajba látni.
The changes in the sediment layers reflected contemporary changes in sea level, and it turned out that a mangrove swamp had also formed in the area, providing opportunities for the existence of many organisms, including marine animals.
About 8,000 years old petroglyphs from Arnhem Land
Source: Wikimedia Commons
The changing environment inspired the art of the Aborigines who live here and the animals depicted. With the transformation, fish, crocodiles, large kangaroos, and birds appeared on the artwork, reflecting the change people went through during the Ice Age.
Aboriginal (modern) artwork in the area. Man has been continuously present in this region for tens of thousands of years.
Source: Flinders University
“Based on these findings, all of the Pleistocene sites in western Arnhem Land were close to the ocean, and thus there were mangrove swamps at some point in the landscape transformation.” Dr. Jarad Nulsar, Head of Research, explained. He added that the ancient geographic location of the sites must also be taken into account when examining the findings, that is, the changing stone tools, food sources, and the isotopic composition of the remains of this era.
ERT tests can be done quickly and inexpensively, so this method can be used to map a large part of Australia with its help, and thus a lot of information can be obtained about the geographical history of the continent. For example, it can be used to show where there is a chance to find a buried archaeological site in this area of extraordinary historical importance, and researchers believe that the method can also reveal former rubbish heaps, which is a real gold mine for archaeologists.
