One Tcf From One Well: The Design of a 500 MMscf/D Subsea Well for Offshore Mega Gas Fields

Abstract

With the continued discovery of large gas fields worldwide that have highly prolific sandstone reservoirs, the ability to design wells capable of recovering ultra-high volumes of gas will become of great interest. The project teams for these fields will be challenged to develop the fields with the smallest well count possible. The results from this study could prove useful to production and completion teams supporting large gas field developments. This paper presents a study to determine the feasibility of a subsea sand control gas well producing at rates up to 500 MMscf/D and recovering one trillion cubic feet (Tcf) of gas. Because the size of recent gas field discoveries is so large, reservoir simulation models will show that recoveries exceeding one Tcf are possible from a single location. Considering the huge cost to install deep water subsea sand controlled wells, reducing the total well count necessary to deplete the field is a business imperative. The results of the study show that completing a sand control well that can produce 500 MMscf/D and recover one Tcf is plausible. The details of the well productivity, completion design concepts and relevant comparison of analogue fields is shown. In conclusion, production and completion engineers involved in development of mega gas fields should at least consider planning for such wells.