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Paleolithic Age (Tampanian) Stone ToolProduction ‘Workshops’, Kota Tampan,Perak — Was it Toba which Destroyed theIndustry 70 000 Years Ago?P. LoganathanFellow, Institute of Geology Malaysia(e-mail: logan@akademisains.gov.my)CommentaryThe thirty-two year old man, 150 cm in height, and old for his age, was hunched over a piece of flat-shaped white rock andchipping away at the edges of the rock with another hand-held piece of rock, this one of a reddish-brown colour. He wassitting along a river bank terrace surrounding a lake, just meters away from where he sat and worked. A large river flowedalongside the lake. It was growing dark and he had been at his task since day-light broke in this river valley. He heard asound, turned around and saw his wife, bringing him some roasted meat, the remains of a monkey the hunters of his villagehad killed the previous day. His two children were with her. He stopped work and sat down on a boulder and took themeat from her and began cutting it with a sharp-edged stone. He grunted with satisfaction, pleased that his earlier workwas good. It would fetch a good bargain, maybe a porcupine or fish or even a monitor lizard in exchange. His tools werein good demand and he was a well-known tool-maker in the area. He gave his wife and children pieces of meat and beganchewing on his. He looked around at the many pieces of smooth rock around him, and pointed to a few pieces. These willmake good scrapers and arrow-heads. His wife nodded in agreement. His children ran to pick up the pieces and turnedthem over to look at them.It was then they heard a loud thunderous sound, coming from the direction where the sun set. He grew fearful andshouted to his family to gather up his work and they ran towards their village, a kilometre away. It must be the river, heshouted to his family, as they ran uphill away from the river. He had seen how the river would occasionally flood and wipeaway his and the others’ little workshop huts on the river-bank in the past. He had not had time to pick up his finished work,some 8 pieces, a morning’s work.Minutes later, the earth beneath their feet shook. His children tripped and fell. He paused to pick up one and his wifepicked up the younger child and ran into their hut. This is not the river; it was never like this, he thought to himself. Thesky suddenly darkened as he huddled with his family. He called to his neighbours if they knew the source of that sound andthey all answered, maybe a herd of elephants. No, elephants would not have made that sound!Soon, it was quiet again but something strange was happening. Hot ash began to fall and soon fall was getting heavier.He smelt burning which hurt his nose and inside his chest. He looked at his family, all with fearful looks on the faces. Hishut and the others in the village began to smoulder and then catch fire. They all shouted and ran into the river and squatted.There was hissing sounds as the hot ”bits” fell into the river. Some were still hot. The fall grew heavier until everythingaround them, the trees, the rock boulders and the ground was covered in hot, white ash-like material. The next morning, thewhole village moved away; this village was not safe anymore.What he, his family and his village did not know was that a terrestrial super-volcano had erupted in Sumatra.Various researchers had attributed the volcano to be Toba, erupting, they reported, some 74,000 years ago. In a recentpaper, to be published in the Proceedings of the National Academy of Sciences by Storey, Roberts and Saidin (), reported that, by using sanidine (a form of feldspars) crystals extracted fromthe volcanic ash (Figure 1), their astronomically calibrated 1 40 Ar/ 39 Ar for the volcanic ash in the Lenggong Valley gave adetermination of 73.88 ± 0.32 ka (or, thousand years), or 73 880 ±320 years.1 In a paper by Renne et al. (1994) (), they said that “the40 Ar/ 39 Ar radioisotopic dating technique is one of the most precise and versatile methods available for dating events inEarth's history, but the accuracy of this method is limited by the accuracy with which the ages of neutron-fluence monitors(dating standards) are known”. They further stated that “the emerging astronomically calibrated geomagnetic polaritytime scale offers a means to calibrate the ages of 40 Ar/ 39 Ar dating standards that is independent of absolute isotopicabundance measurements”.71