This paper presents geodynamics of the Southern Cis-Urals region. It focuses on seismicity induced by hydrocarbon production by summarizing the published case studies. Natural and man-made changes in bowels of the Earth are usually accompanied by tectonic movements and deformations of earth's surface, which is one of the important factors determining environmental changes and requiring mandatory consideration in engineering-geological surveys and exploitation of deposits. The influence of anthropogenic factors on the geodynamic state of platform areas is considered by the example of Orenburg oil and gas condensate field and Baitugan oil field.

The predominant area of application of the developed methodology is the construction of the distribution of the geodynamic state of the developed hydrocarbon fields in oil and gas basin, and the identification of the corresponding distribution law. A number of the hydrocarbon deposits in terms of geological conditions of occurrence, structure and other parameters are geodynamically hazardous during their development. The Federal Law «On Subsurface Resources» (Article 24) requires conducting a complex of geological, surveying, and other observations sufficient for ensuring a normal technological cycle of work, and the prediction of hazardous situations. The developed methodology based on the construction of aggregated additive models for each reservoir and field is presented. It includes four sequential stages (24 operations): first — prepare geodynamic data; second — determine the geodynamic state of productive strata; third — find the geodynamic state of the developed deposits subsoil; fourth — build the distribution of the bowels geodynamic state of these fields for the entire oil and gas basin and identify the relevant distribution law. Oil and gas basin in the west of the Orenburg Region (Volga — Ural and Caspian oil and gas provinces) is considered as an example of implementation. Unique data of twenty geodynamic parameters of 320 productive strata (56 fields) were used. It is revealed that in accordance with the Pearson criterion, the theoretical data with a high confidence probability (95 %) correspond to the law of normal distribution. Developed methodology has significant technical and economic advantages, since it allows to identify the geodynamic state of productive strata and subsoil of the fields being developed, to identify hazardous geodynamic processes and to choose rational modes for the development of hydrocarbon deposits.

The article raises a problem of dangerous geodynamic processes taking place in the eastern part of Orenburg region. The analysis of subsoil geodynamic state of Orenburg region is completed. Effective monitoring of geodynamic processes in the eastern part of Orenburg region using a seismological network is proposed and justified. Seismic events with a magnitude of ML> 2.0 are confidently recorded on this territory as well as subsidence of land surface reaching 50 cm per year. According to long-term monitoring of seismic events in the eastern part of the Orenburg region, a repetition schedule of seismic events was constructed. It allowed us to make a conclusion of the reason for increased geodynamic activity in this region is high technogenic load on geological environment. To study abnormally high seismic activity in the East Orenburg region, it is necessary to create a seismological network of 3-4 seismic stations in the territory of seismic activity in the Gaysky and Novooorsky districts near the cities of Orsk and Gai, Iriklinskaya State District Power Station and Iriklinskoye Reservoir. This will help to identify seismic activity causes and sources, level of danger, help to develop measures for reducing seismicity and increase the security of specific objects of society, industry and energy.

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