Jean Riemersma, Engineer

Jean Riemersma, the muchrespected Chief Surveyor of Shell International (1977–1987), died unexpectedly at his home in The Netherlands on 21st November aged 77. The international offshore oil and gas survey community will remember him as a ground-breaking hydrographic surveyor whose unrelenting, but ultimately successful, battle to introduce real-time quality control for offshore survey positioning remains a lasting memorial to his professional tenacity. In the early days of radio positioning, the intersection of two radio-generated position lines was accepted as the norm. Jean insisted on and persevered relentlessly to add redundant information (in the form of a third radio position line). Although well justified, this was both costly and unpopular at the time.

Jean graduated as a Geodetic Engineer from the Technical University, Delft and joined Shell International as a land surveyor in 1958. By the early 1960s, Jean had completed a complex tellurometer control point survey in the middle of the Libyan Desert just as the exploration for North Sea hydrocarbons began – he was duly re-assigned to assist. The existing European Decca Main Chain Navigation system used for navigation in the North Sea was not designed or intended to be used for high-precision exploration surveys and so Jean became involved in setting up the Decca SeaSearch II Chain. This system was more accurate than the Decca Main Chain, but also had several disadvantages, including the loss of lane identification during a survey and at night-time it was subject to the ‘skywave’ effect. To overcome the problem of loosing lane identification, buoys were deployed from the survey vessel in the evening. These were then used to re-establish the lane count the next morning and the survey could then continue. This was Jean’s first involvement in offshore surveys.

This North Sea experience led Jean to be selected to head Shell’s survey department in Brunei, Northwest Borneo, where offshore oil exploration had experienced a sudden surge. The offshore operational area was about 1,000 kilometres long and extended 100 kilometres out to sea. As head of the department, Jean set up a smooth-running organisation and used the latest radio-positioning systems, which were based on the Decca HiFix chains, together with the then ‘state-of-the-art’ computers to start to automate the survey process. His first computer program was a coordinate transformation routine that converted HiFix readings to rectangular coordinates. This was a huge step forward because at the time HiFix readings were still plotted and computed by hand. The time saving was a factor of 20, from 20 minutes to 1 minute per fix. His record during the 11 years he worked in Brunei did much to enhance his reputation and constituted a very important period in his professional life; it was also a memorable period for his accompanying family.

?Never a person to shy away from unpopular decisions, Jean’s character can best be illustrated by an episode in Brunei. His topographic department was also responsible for collecting meteorological information and making basic weather forecasts. Aftera typhoon had left a path of destructionover the Philippines, the department’s elementary weather maps indicated that the eye of the storm was now heading towards Shell’s operational area. Jean approached management, recommending that all operations should be stopped and personnel evacuated to shore. This recommen­dation was met with much opposition, as it would cost Shell tens of thousands of dollars in lost revenue. However, he persisted and his opinion prevailed. Eventually, the storm suddenly veered to the north, an outcome that even today, given the availability of much more sophisticated observations and satellite images, would surprise the most expert forecaster of tropical storms.

After Brunei, Jean was posted to the UK were he was appointed Head of Survey for Shell Exploration & Production. This brought new challenges, which included the positioning of large drilling barges and oil platforms, such as the Condeep range of production platforms in the deep waters of the northern North Sea. He was also involved in pipeline route surveys and pipeline construction with some difficult landfalls onto the rocky coast of Shetland, where the use of underwater acoustic positioning became essential.

In 1977, Jean became Chief Surveyor of Shell in the Head Office in The Hague. More than ever, he established his – and Shell’s – reputation amongst the survey contractors as a demanding and difficult client. This was due to his insistence on high survey standards and the introduction of quality control for offshore positioning on a worldwide basis. Quality control introduces a feeling of confidence in the reliability of offshore survey data, a confidence that did not exist before that time. There was much resistance to the introduction of quality control, by both survey contractors and position system manufacturers alike who did not see the need to collect additional position data and were adverse to the inevitable extra expense. They were reluctant to change and, in the case of the manufacturers, unwilling to modify their equipment. Only after the quality control specifications were set out in Shell tender documents was change forthcoming.

After his retirement from Shell in 1987, Jean continued to be active in the surveying industry, continuing as Chairman of Commission 4, Hydrography (1984–1987) of the International Federation of Surveyors (FIG), President (1987–1989) of the Hydrographic Society, President of the Comité de Liaison des Géomètres-Experts Europeans (1991–1992) and Managing Director of B6 Landmeet­kundige Diensten BV (1990–1997), a joint venture of the six major land-surveying companies in The Netherlands and the Dutch Cadastre.

Jean always radiated optimism and self-confidence. In his work he never saw problems, only challenges that he embraced with vigour. Colleagues and friends will mourn a warm-hearted character and born leader, who had an inspiring and professional approach to his work. He leaves behind a wife, three children (two of whom followed him into the surveying profession) and nine grandchildren.