Study on geochemistry of sea water intrusion effect in Jailolo geothermal system

The possibility of seawater intrusion in geothermal systems is very likely to occur. This is caused by several locations of geothermal systems which are very close to the coast. This paper presents a geochemical analysis of the data manifestations of water and gas, to determine the effect of sea water on the Jailolo geothermal system. From the results of the water analysis, it is clear that the effect of sea water intrusion on the Jailolo geothermal system is shown in the anions and cations diagrams, which is almost all of the plots very close to the seawater points. So that the next analysis is focused on the position of mixing sea water with reservoir water and correction of the parameters that are affected by the mixing of sea water. It is intended that the resulting geochemical model can describe the actual reservoir conditions. If we did not include the correction factor to the calculation this will lead into mislead assessment of the reservoir temperature of geochemistry model which is the final result of the study/assessment. It is also necessary take into account for the next step of the process which is exploitation phase.