A Novel Approach for New Well Placements Using Dynamic Data and Flowing Material Balance

Abstrak

W Field is a carbonate reservoir which produced on a thin oil rim with a gas cap. The W field is one of the newest fields in UP area and producing from 4 wells within 1-year production period. The adjacent field with similar features with W field shows challenging in field development with low recovery factors, especially in selecting new well proposed locations. Furthermore, dynamic simulation couldn’t be used, since history matching always become problems in this field where fracture and vugs have big contributions to well performances. Even generating bubble maps using decline curve analysis will give high uncertainty since well recovery factor is unknown. Therefore, reliable methods to determine each well connecting volume is needed.

Flowing material balance (FMB) as a new approach in Production data analysis and Rate Transient Analysis (RTA) with a type curve will be used as the basis to determine the connecting volume from each well. Compared with conventional material balance where shut in is required to get the average reservoir pressure, FMB will use historical rate and flowing pressure to derive  average reservoir pressure and determining connected Original Hydrocarbon in Place. By using FMB, it can also be seen whether the wells that have been producing interfere with each other thus have connecting volume between wells. All above solutions were preferable since no shut in is required.

The results show Flowing Material Balance and Rate Transient Analysis give reliable connecting volume. The derived connecting volume then used to generate bubble maps as a guidance for estimating new well placements. The resulted maps, guided with the static model volumetric show the estimated drainage area and possible additional drainage from new wells to increase hydrocarbon recovery. Therefore, in W field 2 new wells have been proposed to be drilled in the following years.