The eruption was about 140 million years ago, a time when dinosaurs roamed the world. It is estimated that approximately 70 cubic kms of rubble were erupted during the single event. This compares with only 2 cubic kms for the Mt. St. Helens eruption and 12 cubic kms for the Krakatau eruption of 1883, which dispersed haze all over the world.
The talk describes the clues that led to the discovery, which parts of Hong Kong are underlain by the volcano and what are its structural components. It also discusses how the volume of the eruption was estimated, how the eruption might have unfolded, and what would have been the local and global effects.
Dr Roderick Sewell has been a member of the Hong Kong Geological Survey for 26 years. He read geology at the University of Canterbury, where he also wrote his PhD on an extinct volcano in New Zealand. He then worked for the New Zealand Geological Survey studying volcanic geology and tectonics. Since arriving in Hong Kong, Dr Sewell has been involved in geological surveying, radiometric dating of rocks, concrete assessment, tunnel geology and studies of landslide activity.
Dr Sewell has co-authored several books, papers and maps on the geology of Hong Kong, New Zealand and Antarctica. He is Chief Training Geologist in the Geotechnical Engineering Office and is an Honorary Professor in the Department of Earth Sciences at the University of Hong Kong. He currently heads the Hong Kong Geological Survey of the Hong Kong Government. Dr Sewell is an elected Fellow of the Geological Society of London.
Members of the RGS and the Hong Kong Club and their guests are most welcome to attend this event, which is HK$150 for Members and HK$200 for guests and others. Members of the Hong Kong Club should apply through the Club's Banqueting office; Members of the RGS and their guests should apply here