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In our country there is plenty of CBM (coalbed methane), but the state of CBM itself, unique output mechanism and low saturation, low permeability, low reservoir pressure and high gas content, et al. determine the low efficiency of it, so in order to improve CBM recovery, combined with the successful experience of north American shale gas reservoir by SRV(stimulated reservoir volume), the writer summarizes the implementation of SRV, deeply analyzes effectiveness and limitations of this new technology in CBM development. The results of practical research and theoretical analysis show that SRV in the coal reservoir can achieve the desired effect on the condition that there are great quantity of natural fractures, joints and bedding, weak structure surface development in the reservoir, the rock brittleness index is greater than 40 and horizontal principal stress difference is relatively smaller. Finally, simulating a well’s condition by the MEYER software, the result shows that SRV is feasible in coal reservoir, which will create important guiding significance and practical value for the exploration of CBM.

As a kind of emerging energy with massive reserves, natural gas hydrates are becoming the hot spot of global research. The elastic properties of gas hydrate bearing sediments (HBS) are the fundamental parameters for gas hydrates exploration and resource evaluations. As the original coring in HBS is difficult and expensive, experimental method is important to study the problem. An acoustic wave in-situ measuring system for HBS was developed. Using the in-situ method, hydrate bearing rock samples of different hydrate saturation were synthesized, of which the supersonic wave measurement was carried out under different confining pressure. According to the elasticity theory, the dynamic elastic parameters were obtained using the measured ultrasonic wave velocity. The results show that compressional and shear waves increase with the confining pressure and hydrate saturation increasing, and so the dynamic elastic modulus is.

On the basis of low permeability exploiting statement, “Exploding in fracture” is present in this paper and the feasibility and safety of this technology is also analyzed. It is found that the rock damage and fracture by shock wave in “Exploding in Fracture” can be simulated by the experiment of exploding on the surface of the cement sample in deep water. The damage and fracture of the cement sample, and the wave propagation proceed, and the damage and fracture mechanism are described qualitatively. It is found that the micro-fractures and compacted wave have an intimate relationship with the initial damage of the sample. The numerical simulation result is accordant with the experiment result. It also concluded that the qualitative explanation of rock damage and fracture mechanism is right. The compacted damage zone has definite permeability, which has an important means to “Exploding in Fracture” technology.

The application of well logging data is one of the most common prediction methods of pore pressure. According to acquire the field practical applicability and high accuracy, Eaton’s method proposed a definition of area index which can present the local complex factors resulting in abnormal pressure regardless of overpressure generating mechanisms. However, the computed area index is generally calculated by one layer in the whole formation, thereby generating some prediction errors. This paper presents a new method called “Hierarchical Eaton’s Method” that is considering different computed area indexes from different layers. Therefore, the revised Eaton’s method can have higher accuracy comparing to traditional Eaton’s method. Moreover, the application of this new method in HPHT wells in Yinggehai basin, China has been discussed in this paper and indicates the field feasibility of this approach.