structures. Among the artifacts recovered were a piece of wood, pottery shards, weathered stones initially described as hand tools, fossilized bones, and a tooth. Artifacts were sent to the National Geophysical Research Institute (NGRI) in Hyderabad, India, the Birbal Sahni Institute of Paleobotany (BSIP) in Lucknow, India, and the Physical Research Laboratory in Ahmedabad, India. The piece of wood was carbon dated to an age of 9,500 years old. NIOT returned for further investigation in the Gulf from October 2002 to January 2003. During these excavations, NIOT reported finding two paleochannels flanked by rectangular and square basement-like features. Artifacts were recovered by means of dredging, including pottery sherds, microliths, wattle and daub remains, and hearth materials. These artifacts were sent for dating at the laboratories of Manipur University and Oxford University. The wattle and daub remains are composed of locally available clay, reed, husk, pottery pieces, and pieces of fresh water shell. The wattle and daub also shows evidence of partial burning. The most recent work in the Gulf of Khambhat took place from October 2003 to January 2004 and was primarily a geologic study. Techniques used during this investigation include bathymetry survey, sub-bottom survey, side-scan survey, and magnetic survey. One of the major findings from this investigation concerns the orientation of sand ripples at the site. NIOT researchers claim that there are two sets of ripples visible at the site; one set is a natural feature formed by tidal currents, whilst they say the other set has formed in relation to underlying structural features. Carbon dates One of the main controversies surrounding the GKCC is the dated piece of wood. D. P. Agrawal, chairman of the Paleoclimate Group and founder of Carbon-14 testing facilities in India stated in an article in Frontline Magazine that the piece was dated twice, at separate laboratories. The NGRI in Hyderabad returned a date of 7190 BC and the BSIP in Hannover returned a date of 7545-7490 BC. Some archeologists, Agrawal in particular, contest that the discovery of an ancient piece of wood does not imply the discovery of an ancient civilization. Agrawal argues that the wood piece is a common find, given that 20,000 years ago the Arabian Sea was lower than its current level, and that the gradual sea level rise submerged entire forests. Artifacts Another controversial issue are the artifacts retrieved from the site during the various excavations. It is disputed