C. Gouridasan Nair
Radiocarbon dating from Pattanam aids understanding of Iron Age chronology
THIRUVANANTHAPURAM: Kerala, or what later came to comprise it, may have had maritime contacts with far off lands as far back in time as 500 BC or even earlier, archaeological studies now suggest.
The Kerala Council for Historical Research (KCHR), which last year conducted archaeological explorations at Pattanam, 7 kilometres south of Kodungallur in Ernakulam district, says scientific analyses of material collected from the area have shown the maritime activity there to be as old as 500 BC “The artefacts recovered from the excavation site suggest that Pattanam, with a hinterland port and a multicultural settlement, may have had links with the Mediterranean, the Red Sea, the Arabian Sea and the South China Sea rims since the Early Historic Period of South India,” said P. J. Cherian, Director, KCHR.
The KCHR undertook the excavations in February-April 2007 and sent five samples to the Institute of Physics (IoP), Bhubaneswar. These were charcoal samples from the Iron Age layer and parts of a wooden canoe and bollards (stakes used to secure canoes and boats) recovered from a waterlogged context at the site. As determined through analysis using Accelerator Mass Spectrometry (AMS) radiocarbon (14 C), their mean calendar dates fall around 500 BC, with a span of uncertainty of less than a century, Dr. Cherian said.
According to him, it is for the first time that 14C AMS analysis was done for an archaeological site in Kerala. This dating, he said, was crucial to understanding the cultural sequence of the site which was active since the Iron Age.
The project was undertaken by the KCHR as part of the Muziris Heritage Project of the Kerala Government with technical assistance from a dozen national-level scientific institutes and laboratories. The organic samples have been sent to the National Geophysical Research Institute (NGRI), Hyderabad, for analysis employing conventional or radiometric method of 14C dating, he said.
T. Satyamurthy, former Superintending Archaeologist, Archaeological Survey of India (ASI), told The Hindu over the phone from Chennai that the Pattanam findings were quite encouraging.
He, however, called for more horizontal excavations with the involvement of experts to further validate the initial findings.
More samples establishing the antiquity of the site and activities there are called for to come to firm conclusions about the findings. This would call for excavations on a larger scale, he said.
Dr. Cherian said Pattanam is the first habitation site of the Iron Age unearthed in Kerala. Since previous enquiries were confined to megalithic burials, no firm dates were available for the Iron Age, except in a few instances such as Mangadu (circa 1000 BC) and Kunnoni. The radiocarbon dating from Pattanam will aid in understanding the Iron Age chronology of Kerala. The 14C ages of the charcoal samples from the lower-most sand deposits in the trenches at Pattanam suggest that their calibrated date range (14C ages adjusted for past fluctuations of 14C in the environment) is from 1300 BC to 200 BC and 2500 BC to 100 AD, respectively. The range, Dr. Cherian said, has been kept wide enough so that the probability of accuracy will be 95 per cent. This suggests that Pattanam witnessed the Iron Age occupation during the first half of the first millennium BC. Indigenous people seem to have settled in the area during the Iron Age when it was covered by beach sand. The occupation must have been sparse as evidenced by mostly black-and-red ware and other typical ‘megalithic’ pottery recovered from the more than 60-cm thick sand deposits in the locality, he added.
Canoe, bollard samples
The other samples analysed by the IoP were parts of a canoe and bollards belonging to a fascinating hinterland port with wharf-like features. The wood was identified as Artocarpus hirsutus Lamk. (wild jack or ‘anjily’) and Tectona grandis (teak) by the Kerala Forest Research Institute, Thrissur. The 14C date range of the canoe sample is 1300 BC to 100 BC, (that is, 700 plus or minus 600 BC with 95 per cent probability). For the two bollard samples, the 14C date range is 800 BC to 200 BC (500 plus or minus 300 BC, with 95 per cent probability) and 1100 BC to 1300 AD, (A.D. 100 plus or minus 1200 with 95 per cent probability), respectively.
Dr. Cherian said the 14C AMS dates suggest that the Pattanam canoe can be the earliest known canoe in India. The other evidence of an early boat discovered from the waterlogged deposit at Thaikkal near Cherthala in Alappuzha district two years ago was dated to AD 13th-14th centuries. The error weighted mean for all five samples analysed is 500 plus or minus 80 BC. Corroborative analysis in relation to the other artefacts recovered is necessary for a clearer picture of the chronology of the site.
The AMS analysis was undertaken by scientists of the AMS Radiocarbon Laboratory of the IoP, led by Dr. G.V. Ravi Prasad and Dr. Koushik Dutta. The KCHR team was led by, apart from Dr. Cherian, V. Selvakumar (Tamil University, Thanjavur) and K.P. Shajan.
The ASI has granted a licence to the KCHR for a second excavation and the work is set to begin in February. Besides the excavation at Pattanam, the licence will enable the KCHR to explore within 50 km of Kodungallur. Underwater exploration in waterbodies in a 20-km radius is also included.
The project, to be undertaken in collaboration with the Southern Naval Command of the Indian Navy and the State Archaeology Department, will have Professor K. Rajan (Pondicherry University), Dr. Selvakumar and Dr. Shajan as co-directors.