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Dear All - there's still time! Please consider submitting an abstract to the session 'The DUPAL anomaly: a 30-year retrospective - what have we learnt?', at EGU Vienna later this year [Session: GMPV3/GD3.6]. The solicited speaker will be Prof. Bill White. The deadline is the 16th January 2014 - description of the session below. Please pass this message on to colleagues who may be interested. Many thanks, and we hope to see you there, Tiffany Barry and Cornelia Class (conveners) Session description Thirty years ago Dupré and Allègre (1983) described an isotopic characteristic of basalts around the Indian Ocean. The following year, in a seminal paper, Hart (1984) coined the term 'DupAl', and noted that the isotope anomaly is global-encircling in its extent and characteristic for the southern hemisphere. Both papers appreciated the importance of the DUPAL anomaly for understanding how the mantle mixes andconvects, and concluded that at least some areas of the mantle do not mix thoroughly, even on long geological timescales. Since Hart's paper, the geochemical signatures that define the DUPAL anomaly have been found elsewhere around the globe, even in the Arctic, and in ancient oceans. In addition, tomographic studies have identified LLSVPs at the base of the mantle and it has been suggested that there is a relationship between the LLSVPs and the DUPAL anomaly measured in oceanic basalts. However, others have suggested that the DUPAL signature in some areas is a shallow feature reflecting recycling of continental lithospheric mantle into the asthenosphere during recent continental breakup. The discussion continues: Is the DUPAL anomaly a shallow or deep mantle feature, or both? What have we learnt about the origins of this geochemical anomaly from its current and ancient distributions and its relative position to the LLSVPs? Can geodynamic modelling explain the preservation of long-lived geochemical features like the DUPAL anomaly? How long has the anomaly been around and how did it form? We welcome contributions from geochemists, geophysicists, and geodynamic modellers to look afresh at where the concept of the DUPAL anomaly has taken us in our understanding of how the mantle works today and in the past millions of years and longer. What future research directions might help us answer some of the remaining questions? http://meetingorganizer.copernicus.org/EGU2014/session/15747 Thanks, Tiffany ([log in to unmask]<mailto:[log in to unmask]>) Dr Tiffany Barry NERC Research Fellow ---------------------------------------------- Telephone: 00 44 (0)116 2523924 Dept. of Geology University of Leicester University Road, Leicester LE1 7RH, UK