Abstract

Seguni Field is located in Unocal Indonesia's offshore Balikpapan Block. The field was discovered in June 1995. Its reserves were calculated to be small; therefore, the cost for a full-scaled development of Seguni would have to be minimal. For such a marginal field, an innovative approach is required to maximize the economic return. An innovation in designing a small platform structure, named Stacked Template Structure, has enabled Unocal Indonesia to develop and expand the field economically.

The Stacked Template Structure (STS) uses well conductors as the platform legs. The 3-leg platform initially could accommodate four well slots only. However, with the use of wellhead splitter in the latest technology, the amount of well slots could be expanded up to eight. In the first phase of the project, four wells were drilled and completed from the first STS. In the second phase, seven more wells were drilled from the second STS, which was an improved version from the first STS.

As the platform is not equipped with production facilities (i.e. separator), the oil and gas are sent through a two-phase flow line to the adjacent Sepinggan Field for further processing. Sharing an existing infrastructure makes the platform size to be smaller compared to a full-sized conventional platform. This contributes to money saving for the project.

This paper discusses the application of STS in developing the Seguni Field.