Former head of the UK Ministry of Defence CTBT Monitoring Unit, which is part of the UK Atomic Weapons Establishment.
The Unit is responsible for providing authoritative advice to the UK Government on issues related to the detection, location and identification of nuclear explosions and is currently the UK’s CTBT National Data Centre (NDC).
Marshall has been involved in nuclear test detection research since 1958 and has authored or co-authored numerous peer reviewed papers on seismological source discrimination. He was a technical advisor to the UK Delegation at the 1977-1980 USSR, U.S., and UK Trilateral Test Ban negotiations in Geneva and a UK Delegate to the UN Committee on Disarmament meetings of the Group of Scientific Experts from 1975 to 1988.
He was a member of the UK Delegation to the 1994-1996 CTBT negotiations and was Chairman of the Scientific Expert Group responsible for the design of the International Monitoring System. He is now semi-retired but continues to be involved in CTBT monitoring activities on a part-time basis with the UK NDC.
In recognition of his contributions to arms control verification, Marshall was awarded the OBE* in 1990 and was appointed to the CMG* in 2002.
*The Companions of the Order of St Michael and St George (CMG)
* The Order of the British Empire (OBE)