Selection of oil/gas fields development modes in sub-polar offshore areas

Russian Far-East Sakhalin Island continental shelf has abundant oil/gas resources, but it is located in sub-polar offshore areas, so it has severe sea ice in winter. Yearly ice period is over 180 days and single layer of ice can be up to 1 m. Moreover, Sakhalin Island is on the intersection of several tectonic plates, so there are frequent earthquakes and it is also of great difficulty to develop the regional offshore oil/gas fields. In line with different local oil/gas fields, it is very critical to select a development mode suitable its characteristics. By analyzing the development practices for some existing oil/gas fields in this sea area, this paper has summarized the basis for selection of oil/gas field development modes under different conditions for sub-polar offshore areas, compared the costs of single wells under various development modes and recommended a favorable development program for WEINI condensate gas field in this area. This selection method for development mode of oil/gas fields in sub-polar offshore areas fully takes into account the environment factors of sub-polar offshore areas and can help operators make quick and effective decisions in practice.