One of the major challenges, currently facing the Russian oil industry, is the development of unconventional reserves, including the Bazhenov Formation sediments to maintain and possibly increase oil production in Western Siberia. During the May meeting of the Moscow SPE section, a technology of development complex reservoirs will be discussed. We are talking about well-established multi-stage hydraulic fracturing (frac), accompanied by microseismic monitoring (MSM).
This technology was the breakthrough in the development of unconventional reservoirs in United States, which, in some approximation have similar porosity and mechanical properties with formations of Western Siberia. Today, the multistage hydraulic fracturing in horizontal wells together with microseismic monitoring (including real-time), is one of the most successful technologies in development of low-permeable reservoirs.
Most reservoirs are naturally fractured, which results in creating of very complex system of cracks. Created fractures not always propagate perpendicularly to the known stress direction. Always, the system is much more complex, and its parameters cannot be predicted in advance. Test fracturing of rock samples on the surface in conditions, close to reservoir, showed that the development of hydraulic fracture is not a purely mechanical nature, but probably is fractal.
Using MSM monitoring for observation of fractures propagation during hydraulic fracturing helps to optimize frac design, determine the optimal number of stages for the well and to change the trajectory of horizontal wells according to local stress direction in the area of investigation. Also, it helps to reduce the risk of fracture propagation into water-saturated formations.
MSM has been successfully used in Russia, Western Siberia. The results and perspectives of this method will be discussed during May meeting.
About the Author
Anna Rubtsova is working as a Borehole Seismic Geophysicist in Weatherford’s Petroleum Consulting Department. Anna has a Master degree in Geophysics from Novosibirsk State University and prior joining the Weatherford has been working in Seismology. Anna participated in all projects on microseismic monitoring of hydraulic fracturing, done by Weatherford in Russia from 2012 to 2104, and also participated in several projects in the United States and China. The author is an active participant of various conferences in the development of unconventional resources, in cooperation with foreign colleagues published a series of articles on microseismic.