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The mechanisms of joint influence of mountain and reservoir pressures, saturating fluid, structure elements of rocks and external dynamic effects on their behavior in natural conditions, in particular near of the well, are investigated. With specific examples, it is shown that the behavior of rocks with such a set of influencing factors is determined by the laws of synergetics and the combined action of external influences, uneven stress-strain state of the rocks, the pore pressure and chemo mechanical effects. Examples are the results of gas-flow and gas-metric studies of closed wells, as well as the results of explosive perforation and intensification of producing wellbores at different depths. Defects occurrence in minerals with a high modulus of elasticity is initiated by an external dynamic effect and independently under the action of the saturating fluid. Then, under volumetric non-uniform compression and reservoir pressure, gradual fracturing of terrigenous rocks occurs at the micro and macro level. The result of these processes is the formation of areas of the improved permeability near the wells during drilling, production and suspending. When drilling on traditional technology they will impair formation reservoir properties via infiltration of water and solid phase. In oil and gas wells and in closed wells - improve these properties. Analysis of the behavior of rocks from the synergetic position shows that the best mode of loading on the reservoir during wells drilling, wells completion and oil and gas production is depression (reduced pressure) on the reservoir. The known and new promising technologies for the intensification of oil and gas production are determined.

Purpose. To study the laws of deformation and destruction of brittle and ductile rocks and concretes under explosion of industrial shaped charges. Methods.In experiments, the following methods of investigation were used: method of contact sensors for determination of jet velocity; determination of the ultrasonic wave velocity in the concrete samples; methods of optical and electronic microscopy; X-ray phase analysis; measuring and visual analysis of the dimensions and nature of deformation and destruction zones.Findings. The work describes the experimental data on the destruction of barriers made of concrete, granite, steel ST 3, AMC-n alloy, and zinc by the explosions of shaped charges of serial production with porous liners. Calculation formulas for estimating the radius of a destruction zone of geomaterials and rocks in case of a semi-infinite barrier are suggested. The calculation method is based on the estimation of energy impact on the rock by jet penetration velocity into the barrier. Jet velocities are determined experimentally and by engineering methods. The reasons for deviations in the hole shape and deflection of the destruction zone from the symmetry axis were determined.Originality. The modes of penetration of shaped jets into rocks of different porosity, the size of the fracture zone around the hole and the causes and mechanisms of the deviations of the hole shape from the symmetric one are established. Practical implications.The results of the research will be used to design blasting-and-perforation operations in geotechnological wells and can be used to design initiating devices for borehole charges.

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The paper aims to examine the suitability of A. S. Balankin brittle fracture criterion in predicting the of large-scale coal and gas outbursts in underground coal mines under compression load. Formation of dissipative structures as cracks and clusters of local microcracking occurs under the influence of the rock pressure. The formation of microdefects in dissipative structures occurs mainly on local anisotropic inclusions. Mechanism of pre-outburst spalling of gas-saturated coal is analyzed. Destruction (primary outburst) occurs when the brittle fracture conditions are met. And also in the case of such a ratio of “coal seam thickness – the size of micro defects aggregations”, which provides reduction in coal strength to a minimum. Further destruction occurs by known scenario.

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