The Applications of Tracers in Geothermal Development: the Bulalo, Philippines Experience

Abstract

The Bulalo geothermal field, 70 km southeast of Manila, has been in production since 1979. Sampling of production fluid is regularly conducted to monitor reservoir to exploitation. Natural tracers including chloride, natural tritium, and magnesium have proved useful in characterizing the types and pathways of fluids that enter the Fluid characterization helps reservoir processes which in turn lead to efficient resource management. Chloride monitoring has been very in detecting injection at Bulalo. Now, the western edgefield injectors are shut-in and new injectors are drilled farther west to prevent production losses due to injection breakthrough. Natural tritium is used to define the areas affected by natural groundwater influx, injectate dispersal and other waters such as drilling fluid Based on these data, casing programs were modified for development wells. Monitoring chemical by-products from acid stimulations magnesium provides an additional tool in identifying the permeable pathways and heterogeneities within the Bulalo reservoir.