Mass Extinctions
by
Professor Paul Wignall
on
Thursday, 23 March 2006
2/F Olympic House, So Kong Po, Causeway Bay
Drinks and snacks 6.30 pm; Lecture 7.30 pm We are delighted to welcome to Hong Kong Professor Paul Wignall of Leeds University to lecture on the extraordinary events of mass extinction which have occurred during the world's history. Professor Wignall is a world expert on mass extinctions and their causes and has worked on many of what are described as the "Big Six" as well as several of the smaller ones. The fossil record tells scientists that the evolution and the development of life on Earth has not been a smooth progress. Prolonged intervals of diversification have been interrupted by several catastrophic mass extinction events and many other ones. Understanding the cause of these crises has become a key goal in the earth sciences. Many scenarios involve catastrophic physical events such as giant asteroid impacts, huge outpourings of volcanic material, rapid changes in sealevel, changes in the global oceans and landbased events. Professor Wignall is a leading expert in this field, and in this lecture he explains the basic phenomena and summarises his own involvement in this exciting, highprofile, multidisciplinary area of scientific research. His talk includes a discussion of many new ideas and concentrates on the largest of all the extinctions that happened 251 million years ago. This has been called the endPermian event and it may have removed more than 90% of all the plants and animal species on Earth. To illustrate these, he describes some of the spectacular field locations he has visited as part of his quest, including the mountains of Greenland and southern Tibet and the deserts of the western United States. Professor Wignall and the Hong Kong University Department of Earth Sciences are presently studying the third/fourth largest event that occurred about 260 million years ago. Southern China has some superb sedimentary sequences that provide excellent records of the episode, and following this lecture Professor Paul Wignall goes to China to conduct fieldwork in Guizhou and Guangzi. Paul Wignall is Professor of Palaeoenvironments in the School of Earth and Environmental Sciences at the University of Leeds, UK and head of the Institute of Geological Sciences. He was educated at Oxford and then received his PhD from Birmingham. His interests include ancient environments and mass extinctions, and he has worked in North America, Greenland, many parts of Europe as well as China. He has authored some 100 scientific publications, two books and has appeared in several television documentaries including the BBC's Horizon, for Nature and the Geological Society of London. Members and their guests are most welcome to attend this lecture, which is HK$50 for Members, HK$100 for Members' guests and HK$150 for others.