Inversion modeling of the natural state and production history of Mutnovsky geothermal field in 1986-2006
- 1 — Ph.D., Dr.Sci. professor Saint-Petersburg State University
- 2 — junior researcher Institute of Volcanology and Seismology FEB RAS
Abstract
Numerical 3D model of Mutnovsky geothermal field (Dachny springs), which consist of 517 elements and partially takes into account double porosity, was developed in 1992-1993 using computer program TOUGH2. Calibration of the model was based on data from test yield of the wells and initial distribution of temperature and pressure in the reservoir. This model was used for techno-economic justification of power plant construction (Mutnovskaya GeoES, 2002). The model was recreated in the program PetraSim v.5.2, the calibration was carried out using additional data on production history before year 2006 and inversion iTOUGH2-EOS1 modeling. Comparison of reservoir parameters, estimated using inversion modeling, with previous parameter estimations (given in brackets) showed the following: upflow rate of heat-transfer agent in natural conditions 80.5 (54.1) kg/s, heat flux enthalpy 1430 (1390) kJ/kg, reservoir permeability 27∙10–15-616∙10–15 (3∙10–15-90∙10–15) m2. Inversion modeling was also used to estimate reinjection rates, inflow of meteoric water in the central part of geothermal field and compressibility of reservoir rocks.
Funding
Authors express their gratitude to Yu.N.Manukhin and the Agency of Mineral Resources of Kamchatka for actual data for Mutnovsky field modeling. Authors also express their gratitude to S.Finsterle for consultations on the application of iTOUGH2 software. The research has been carried out with financial support from Russian Science Foundation, project 16-17-10008, and Russian Foundation for Basic Research, project 15-05-00676.