Zebra Geosciences Limited was formed in 2002 by 3 friends who started their journey in geophysics with Seismograph Service Ltd (SSL).  John Drabble who became the SSL VSP processing manager, Maurice Dicks who served as VSP acquisition manager in various countries and Jan Chmielewski a skilled programmer. If you are interested in the VSP group from SSL, take a look at the Borehole Relics website.

John is an Earth Sciences graduate who joined SSL in 1980 as a processing geophysicist in their borehole seismic division. He progressed to the position of VSP processing team leader in their UK head office and worked on the more complex data sets. John’s ability to understand how differing energy arrivals will appear in a VSP data set led to further promotion and a 30 month assignment as head of SSL’s VSP processing centre in Norway. This was followed by a second posting of similar length leading the SSL VSP processing centre in Australia before he was asked to return to head office to assume overall lead of VSP processing operations. In mid 1993 CGG became the owners of the SSL borehole division and John became manager of the whole of the resultant, enlarged, VSP group. John left CGG to return to a more technical position and is the lead geophysicist within Zebra Geosciences.

Sadly John passed away in 2016 but he will always be an integral part of Zebra Geosciences.

Maurice is a Brunel University Electrical & Electronic engineering graduate who joined SSL in 1978 as an engineer for the VSP data acquisition division.  After initial training in the UK, Maurice transferred to the international staff with assignments firstly in Holland then Libya, Egypt, Australia, Indonesia, Norway and South Africa.  During this period Maurice worked with a variety a seismic sources (airguns, waterguns, Vibroseis, weight-drop trucks, explosives, etc.) numerous types of downhole receivers and recorded VSPs in many different environments including the arctic region off Norway, the jungle of Borneo and the Sahara desert.  In 1992, Maurice returned to the UK and ran the new projects arm looking at non-VSP borehole applications, e.g. downhole seismic sources, passive seismic monitoring. Maurice has a wealth of real VSP field experience which is applied to provide genuinely practical designs from Zebra’s VSP survey planning service.

Jan holds a Masters degree in Computing Science from Imperial College, London and has designed the ZebraSeis™ suite of software used by Zebra Geosciences. This contains a set of modules, specified by the processing team, which provide a very efficient platform for the processing and subsequent presentation of VSP data. Jan also has first hand borehole seismic experience having worked as a VSP acquisition specialist for SSL in the 1980s followed by a spell in their programming department before he left to form his own business. Since leaving SSL, Jan has been engaged as an IT consultant by several private firms including M.A.I.D. plc and Reuters as well as public bodies including the U.S. and Polish governments. He has also worked with Learning Tree providing training courses on an international basis; these courses have been attended by in excess of 1,000 IT professionals. Jan’s successful business, Petramode, continues alongside his role with Zebra.