| Deep rock discontinuities(fracture) play a more and more important role in exploration and exploitation of oil & gas. Having been lasting almost one hundred years, using many research methods include geophysical prospecting, well logging, mathematical statistics, nonlinear methods and mechanics, however the predict study on deep rock discontinuities is still a world wide accepted puzzle. Systematically using the technical thoughts and methods of engineering geology, this paper studies the characteristics, development and distribution law of the deep rock discontinuities and the relations between the deep rock discontinuities and the stability of the wall of oil well. And thus formed a set of systematical engineering methods. Combining with the prediction study on the discontinuities (fracture) in OM carbonate rocks of Tazhong 1* faulted zone in Tarim Basin hinterland (burial depth from 4600 to 7000 metres) and the discontinuities (cracks) in Jurassic system petroleum reservoir of the middle Sichuan oil and gas filed, and with the detailed research involved in the influence of the discontinuities on the stability of the well wall, the fundamentals, theories, methods and concrete applications of this technique have been introduced by and large. And the main results are as follow.(1) The genesis patterns and the classification scheme for deep discontinuities, the basis of the prediction of deep rock discontinuities, are presented. Through systematically surveying and studying on the field discontinuities outcrops in Huayinshan area in Sichuan basin, combining with the drill cores observation and the comparing study of the well recording, logging and completting data of the same strata nearby, the genesis patterns of the discontinuities, which based on the ground or surface rock mass and also fit to the deep rock mass, are formed, and the rock discontinuities classification scheme (chart 2-4) for the purpose of deep rock discontinuities prediction is concluded too.(2) Using the technical thoughts and methods of engineering geology, combing with physical simulation, numeric analysis, and genesis patterns and classification scheme of discontinuities, the O2+3 carbonate discontinuities(fracture) of Tazhong 1* faulted zone in Tarim Basin and its development and distribution law are predicted.By studying the results of drill cores observation, homogeneous temperatures of inclosures and rock Kaiser effect, it is presented in mis paper that Tazhong 1" faulted zone has experienced at least three periods of tectonic movements. They are O2+3~S~D period, C~P period, and Xishan period respectively. Correspondingly, there are three stages of tectonic discontinuities in Ow carbonate rocks. Each stage has several concrete types. Mainly as follow: perpendicular tectonic seam, perpendicular shear discontinuities, oblique crossingshear discontinuities, oblique crossing tensile discontinuities, perpendicular complex discontinuities.(2) By synthetically analyzing drill cores, well logging and oil test data, it is presented that discontinuities in O2+3 carbonate discontinuities(fracture) of Tazhong 1* faulted zone are most widespread in the grain limestone section, and in the second place are in the silry banding limestone section and slit contained limestone section. Furthermore, the development of discontinuities is also controlled by tectonic stresses, rockmasses properties, thickness of strata and their tectonic locations. Based on above results, combining with the result from the research on the genesis patterns and classification of the discontinuities in Sichuan region, the genesis patterns of the discontinuities in O2+3 carbonate rocks of Tazhong 1* faulted zone are presented.(3) By testting the rock mechanical properties, and Studying on the analysis of Tazhong 1" faulted zone, modeling analysis, geological mechanical simulation, and comparative analysis on the prototype and model, it is concluded that the discontinuities in O2+3 carbonate rocks of Tazhong 1" faulted zone and the structure ne...
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