The business meeting of SEDI was called to order by the SEDI chair, Kurt Lambeck at 17:30. There were 42 members in attendance from 11 countries. The first item of business was a summary of SEDI related activities during the past four years. A copy of the summary prepared for IUGG is appended to these minutes.

Attention then turned to future activities. Andrew Soward reported on the status of plans for the SEDI 2000 symposium, which is to be held on the campus of the University of Exeter, 30 July - 4 August, 2000. There was some discussion of the scientific content of the symposium and of the format of the scientific presentations. Several people spoke in support of having no contributed oral presentations, with all time allotted to invited summary talks, poster viewing and group discussions.

Regarding the SEDI 2002 symposium, two possibilities were mentioned and briefly discussed. One is to have the 2002 symposium in the USA, hosted by a group at Scripps headed by Kathy Constable and Guy Masters. Another possibility, brought forward by Masaru Kono, is to have the 2002 symposium in Japan. It is anticipated that a decision on the location of the 2002 symposium will be made next year at the SEDI 2000 symposium in Exeter.

Among other meetings of interest, IAGA and IASPEI are planning to hold a joint symposium in Hanoi, Vietnam, 18-30 August, 2001. SEDI has been assisting with the development of a preliminary scientific program and will be expected to help with convening of certain scientific sessions as IAGA and IASPEI. For more information on this meeting visit www.IAGAandIASPEI.org.vn.

The most important item of business was the election of Officers and Advisory Committee of SEDI for 1999-2003. The slate of officers put forth by the nominating committee was approved unanimously. There were several modifications made to the slate of nominees for Advisory Committee before that too was approved unanimously. The Officers and Advisory Committee of SEDI for 1999-2003 are:

Chairman:  David Gubbins, U. Leeds, UK
Vice-Chairman:  Henri-Claude Nataf, Grenoble, France
Secretary:  Michael Brown, U. Washington, USA

Advisory Committee:

Reini Boehler, Germany
Bruce Buffett, Canada
Cathy Constable, USA
Ivan Cupal, Czech Republic
Ibrahim Eltayeb, Oman
Rongshan Fu, China
K. Kurita, Japan
Philippe Gillet, France
Gary Glatzmaier, USA
H. K. Gupta, India
Francios Guyot, France
S.-I. Karato, USA
Ban-Yuan Kuo, Taiwan
Kurt Lambeck, Australia
David Loper, USA
Guy Masters, USA
Jerry Mitrovica, Canada
Andrew Soward, UK
Satoru Tanaka, Japan
Lev Vinnik, Russia
Kathy Whaler, UK
Vladimir Zharkov, Russia

The business meeting concluded with some comments by the Chair, including recognition of the service of the outgoing Vice-Chair (Masaru Kono) and Secretary (David Loper) and by a recommendation from Raymond Hide that Kurt Lambeck be thanked for his service as Chair of SEDI for the past four years, which was heartily endorsed by all present.

David Loper
Secretary 

Inter Union Committee: Study of the Earth's Deep Interior (SEDI), 1995-1999.

The principal function of SEDI is to facilitate cross disciplinary research directed at a better understanding of the structure and dynamics of the Earth's Deep Interior. The definition of what is deep is purposely not well established but a broadly used definition is depths below about 400 km. However, SEDI interest can include the shallower zones if processes therein impinge on the deeper regions. Attention is paid to avoiding overlap with the Lithosphere Program which addressees the shallower regions, with the recently established Gordon Conferences, and with Mathematical Geophysics which addresses more mathematically oriented aspects of the physics of the Earth. Overlaps do, however, occur and this is indeed desirable to ensure that the various groups do not work in isolation of each other.

The main way in which SEDI meets it objective is through the biannual SEDI conference and by supporting symposia at other Earth Sciences venues. The principal ones are the IUGG symposia and the Association symposia, particularly IASPEI and IAGA. In addition, SEDI has supported symposia at EUG, EGS meetings and at the UK Geoscience 1998 conference.

In keeping with past practices at both the Boulder (IUGG 1995) and Birmingham (1999) meetings SEDI was cosponsor of a substantial number of symposia rather than organizing its own symposia. Amongst other reasons, this permits those scientists involved in SEDI activities to permeate the relevant Association programs and to encourage cross-discipline presentations.

The two important SEDI functions since the 1995 IUGG have been the biennial meetings: in Brisbane, Australia, in 1996 and in Tours, France, in 1998. The first meeting was held as an experiment in conjunction with the Western Pacific AGU meeting. This turned out to be successful in that SEDI succeeded in retaining its own identity in its science programs and that it did attract participants who would not normally be associated with SEDI. It was, however, concluded that such joint meetings will be the exception rather than the rule.

The highlight of this meeting was a sharply focused debate on iron in the core including the presentation of new experimental, theoretical and numerical results. Other strong programs included sessions on the physical properties of the deep mantle, including experimental and theoretical results, on geodetic constraints on deep mantle processes and on the geodynamo and core dynamics. .

The 1998 SEDI meeting in Tour, France, attracted a larger audience and resulted in a very intense 5-day program covering all areas of the Earth's deep inerior, including the physical, chemical and thermal constitution of the core and mantle, core mantle interactions, properties and dynamics of the inner core, the geodynamo (theory and observations), and experimental results on the deep earth processes. Both meetings were highly successful in attracting scientists from a wide range of disciplines and one is beginning to see the results of an increasing interaction in the scope of the papers presented. The feature of the SEDI meetings in not having parallel sessions and in allowing sufficient time for discussion during the poster sessions must be one element for this success.

The next SEDI meeting is to be held in Exeter (England) in 2000 and while the program can be expected to have a strong focus on geomagnetism, a broad interdisciplinary program is anticipated.

In addition to the SEDI biennial meetings and the IUGG symposia, SEDI also cosponsored symposia at Association meetings, notably IASPEI in Greece, and IAGA in Sweden. The scope of these symposia is partly restricted by the nature of the Association program but it does appear that SEDI's role is influential in broadening the scope of the meetings.

With the large numbers of competing and/or complimentary meetings held each year one issue that has faced SEDI has been the matter of what symposia to support. The annual EGS and biennial EUG meetings, for example, have raised the question of whether by supporting symposia at all of their meetings we are not diluting the SEDI focus. To this end it has been decided that SEDI supports symposia arranged by the two associations in alternate years: the EUG biennially and the EGS during the intervening years. This is with the proviso that there are no particular compelling reasons exist to do otherwise. It is not the practice of SEDI to support national meetings but one exception was made in that the UK Geoscience 1998 meeting was supported as a once off venture because of the opportune and outstanding program organized on the dynamics of the deep mantle and core with a good cross fertilization of disciplines.

The newly established Gordon Research Conferences (GRC) "The Interior of the Earth" raised some matters of competition with both SEDI and CMG but this is now resolved by the GRC agreeing to hold their meetings in odd numbered years whereas, both SEDI and the Committee for Mathematical Geophysics hold their meetings in even numbered years. The last two have a loose agreement to coordinate the time of their meetings such that participants can attend both with reasonable convenience. With a desire to hold the SEDI meetings outside of north America and Europe from time to time, this has of course, not always been achieved.

In addition to its conference functions SEDI also endeavors to encourage young scientists through the award of the Doornbos Prize at the time of its biennial meetings. This prize is awarded for outstanding presentations by young scientists during the meeting. Recipients in 1996 were

Dr Xiaodong, for his work on the rotation of the inner core, and Drs Sri Widiyantoro and Robert van der Hilst for their work on the tomographic imaging of the mantle.

Recipients in 1998 were

Dr Denis Andrault, for experimental investigations of the iron phase in the core, Dr Andreas Tilgner, for experimental contributions to the understanding of the geodynamo, and Dr Lidunka Vocadlo, for her theoretical work on the properties of iron in the inner core.

The SEDI committee believes that the informal structure of SEDI continues to be highly successful in bringing together scientists from different disciplines and in accentuating new research directions into the structure and dynamics of the deep earth. It is becoming increasingly recognised that progress into the understanding of the deep earth will only come about through a concatenation of the different approaches, experimental, theoretical, and numerical, of the sub-disciplines of geophysics and geochemistry. SEDI serves the purpose of facilitating these linkages and will continue to do so over the next decade.