Impact of Faults on Performance of In-situ Combustion Process-A Case History of Santhal
Gujarat state is having large heavy oil In-place in lndia. This is being operated by state owned Company, Oil & Natural gas Corporation Ltd. (ONGC). Santhal, Balal and Lanwa fields consists the largest portion of In-place oil. Reservoirs of above fields are contiguous to each other, which are only demarcated by geographical boundaries. The oil viscosities range from 60-1000cp along Santhal, Balol and Lanwa fields. Balol and Santhal fields are under commercial In-situ Combustion process (ISC) since 1997. The process has established its efficacy on laboratory, pilot and o- going commercial scale in terms of increase in oil production with occurrence of sustained parameters in produced fluid stream. However, desirable results of the ISC process have not been observed in time frame. Anomalies have observed in terms of fluid migration and chronology of EOR effects in the wells. Such observations has led to study the 3-D seismic in Santhal field far nay anomaly in geological set-up and 4-D seismic study in Balol field in order to direction of the process development. Results of 3-D seismic re-interpretation indicated existence of several faults in Balol and Santhal fields. A detailed time lapsed performance study was carried-out in light of faults emerged in the 3-D seismic study. Subsequently, a time lapsed 3-D study was carried out at Institute of Reservoir Study (IRS) ONGC, in a sector of Balol field, corroborating the fluid migration anomalies in Santhal field, qualifies the observations made in time lapsed study of Santhal field. The current paper deals with possible role of faults (non-sealing/partially sealing) in migration of fluid during ISC Process. A time lapsed performance analysis based on 3-D seismic results was carried out. Observation of the study revealed that emerged faults are not completely sealing in nature. However role of such faults observed in terms of temporarily partial restriction for flue gas migration, a conduit like behaviour resulting into preferential migration of flue gases along the fault direction and flue gas effect in the wells, completed into un-targeted sand suggest juxtaposition of different sands against the faults.
S. K. SINHA R. N. BHATTACHARYA A .C BHANDARI
Oil & Natural Gas Corporation Ltd Oil & Natural gas Corporation Ltd.
国际会议
首届世界重油大会(The Technical Sessions of the First World Heavy Oil Conference)
北京
英文
824-831
2006-11-12（万方平台首次上网日期，不代表论文的发表时间）