Shallow gas: risks and variants of technical-technological solutions when projecting construction of offshore wells
The article deals with the problems of projection of offshore wells construction related to the presence of near-surface gas accumulations. Before projecting, within the framework of a well’s construction studies, the research of the upper portion of the section should be obligatory carried out by means of the high-resolution seismic survey that allows to evaluate the risks of detection of shallow gas accumulations. The article presents the decision-making matrix when selecting wells locations in conditions of shallow gas potential manifestations as well as constructions of the wells tops for a variety of depths of shallow gas possible detection. The technical-technological solutions to be reflected on the project documentation on wells construction is also proposed. The possibility of advance drilling of pilot holes in the centers of offshore operational drilling is analyzed.