(MENAFN - Muscat Daily) The UNESCO World Heritage sites of Bat al Khutm and Al Ayn located east of Ibri in the Dhahirah governorate, which were first discovered in the 1970s, will be once again under intense study by a team of French and Japanese researchers, starting 2013.Although in the past various multinational teams have explored the sites, which form the most complete collection of settlements and necropolises from the 3rd millennium BC in the world, the most revealing findings have been by an American team in 2007. There are currently at least eight Bronze Age towers at Bat and over 500 tombs from the same period.A 2010 survey by the American team incorporated an important geomorphological team from Paris to help understand the fluvial (watercourse) dynamics of Wadi Sharsah and its effects upon the site. ''This survey will be greatly expanded in 2013 with the addition of a Japanese survey team under Yasuhisa Kondo from the Tokyo Institute of Technology and an aerial survey team from the Centre National de la Recherche Scientifique (National Center for Scientific Research) under Roland Besenval from France,'' said Christopher Thornton, deputy director of the Bat Archaeological Project.Initial findings pointed to the hypothesis that people at the site 5,000 years ago were able to manipulate their environment to cultivate crops. Excavation proved that crops like wheat, barley and dates were grown, which could have been done only with the help of alluvium that must have been created by damming the wadis.Excavation of one of the towers, Kasr al Khafaji (Tower 1146), yielded a few surprises. ''The Hafit-period walls underneath it, located 2m below the modern surface, were a complete surprise. Furthermore, the work of the geomorphology team looking at a section of 2.5m of alluvium near this tower has suggested irrigation and human activity at Bat beginning as early as 4000 BCE. These levels will be targeted in the research next year,'' said Thornton.There are two principal areas of the Bat archaeological site. First is the northern hills and high valleys which are filled with Bronze Age tombs from two main periods: Hafit (ca. 3100-2700BC) and Umm an Nar (ca. 2700-2000BC), and are in rem-arkably good condition. The second is agricultural lands to the south, which are notable for the presence of large, circular monuments that have historically been referred to as towers.''The American team's excavations at Bat have entirely changed the way we understand Bronze Age settlements on the Omani Peninsula. The Bat Archaeological Project has demonstrated that the multiple towers at Bat were not utilised synchronously, but were most likely used for short periods of time (100-200 years) before being abandoned when another tower was built.''Thornton added that the combined work of the Danish, French, German, Japanese and American teams in this region has demonstrated that the site of Bat and Al Ayn was a very important area in the Bronze Age.''Further study of the tombs, towers and domestic structures is needed to explain why Bat became a major centre around 5,000 years ago, and why it collapsed after a thousand years of prosperity,'' he said.