The efficient development of tight oil exploration and development domestic and foreign has been a difficult, hot issues, using conventional reservoir reconstruction process, the yield increase is limited. Ordos Basin in the Chang 7 layers of tight oil reserves on behalf of a large scale, widely distributed, in order to reinforce to achieve fifty million tons of Changqing Oilfield stable long-term strategic objectives of the resource base and improve the tight oil well production, faced with enormous challenges. For Changqing Oilfield tight reservoir geological features, learn from foreign experience in tight oil development success, positive change in Changqing Oilfield reservoir reconstruction,approach to volume fracturing as a concept, greatly contributed to the Chang 7 represented tight reservoir of cost effective development, the effect is significant, strategic breakthrough.

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The aim of this study was to propose the workflow for integrated analysis of the 3D geostress and 1D geomechanics of an exploration in a new gas field. This integrated analysis will allow for problems associated with the inaccuracy of 1D geomechanical analysis to be overcome in a region with obvious anticline/syncline structures. The 1D geomechanical analysis of the well in the exploration of a new gas field mainly included the prediction of pore pressure and calculation of the mud weight window for safe drilling. In general, this integrated workflow included both a method for pore pressure prediction and a method for the calculation of the mud weight window, with the numerical solution of 3D geostress plus the interval velocity of formations. The procedure for the calculation of the 3D geostress of a target block was also introduced. Numerical solution of the 3D geostress of the target gas field, as well as solutions of 1D geomechanical analysis, have demonstrated the efficiency and practical use of the proposed theory in the successful drilling of the LT-1 well in the Junggar Basin, Xinjiang, China. For this LT-1 well in the target TS block, there was no logging data to refer to when predicting the pore pressure of undrilled formations. Only 3D geostress could be used to calculate the mud weight window. Influences of anticline structures were considered in the calculation of 3D geostress. Since the accuracy of the numerical solution of 3D geostress is higher than the accuracy of the 1D geostress solution for a single well analysis, the results of pore pressure and the mud weight window are more accurate than those obtained with conventional 1D geostress analysis. Details of the finite element modeling of the 3D geostress field of the TS block is presented along with the solution of the 3D geostress field. With the data of the interval velocity of formations and 3D geostress solution of the TS block, pore pressure prediction was carried out for the 7000 m-deep pilot LT-1 well. Finally, calculations were performed for the values of the mud weight window of the LT-1 well.

The efficient development of low permeability reservoir exploration and development at home and abroad has been a difficult and hot issues. Changqing Oilfield is the permeability, low pressure, low abundance of the "three low" oil and gas fields, is the world famous low permeability. In recent years, with the low permeability of Changqing Oilfield fast on the scale of production, development and gradually increase the difficulty, well production decreased year by year, oil layers, layer contradictions become increasingly prominent. Changqing Oilfield how old stable production, it will be a challenging task. In this paper, Changqing Oilfield per 214 Jiyuan Chang 4 +5 reservoir, for example, focuses on the reservoir of the reservoir by strengthening fine management and implement water policies, improve water technical control, good water injection, inject enough water, improve the capacity of the reservoir stable production, improve development effectiveness.

The presence of natural fractures can significantly affect the quality of hydraulic fracturing operations in tightsand and shale or oil/gas formations. This paper describes the procedure used to model natural fractures with continuum damage tensor and the resulting orthotropic permeability tensor. A damage model that uses damage variable in tensor form is presented. In the procedure presented, a nonnegligible angle is assumed to exist between directions of principal stresses in the formation and in the natural-fractures-related damage tensor, and this difference in orientation is modeled by introducing local directions in the model. A damage-dependent permeability tensor in tabular form is then proposed. A second case scenario when the directions of principal stresses and natural fractures align is also analyzed. Numerical results of fracture distribution are presented for both cases, and differences can be seen from the computed contour of the damage variable. The results indicate that the model can effectively simulate the fracture propagation phenomena during hydraulic fracturing.