Orenburg region is an intrinsically challenging region from oil and gas production standpoint.
With more than 100 oilfields it has conditions varying from deep HPHT wells with tectonically formed traps all the way to shallow sands with high viscosity crude.
Production enhancement by channel hydraulic fracturing with unconventional proppant
Channel fracturing
https://www.earthdoc.org/content/papers/10.3997/2214-4609-pdb.395.IPTC-17409-MS
Elongated proppant
https://onepetro.org/SPERPTC/proceedings-abstract/12ROGC/All-12ROGC/SPE-160242-MS/159007
Chemical composition optimization to restore production on Rostashinskoe field
https://onepetro.org/SPERPTC/proceedings-abstract/14ROGC/All-14ROGC/SPE-171147-MS/212125