The Kowloon Hills To Borehole Wall Stability Of Logging Evaluation Center Of Research

Jiulong Mountain is located in the northern Sichuan basin structure in West Sichuan, the reservoir physical property is poor, which has low porosity, low permeability, as poor gas reservoirs. In the actual drilling, logging and geologic data shows that abnormal high pressure distribution is very complex in the area, and the formation are easy to break. By using the existing acoustic log data, conventional log data, geological data, drilling data, and based on the formation rock mechanics experiment, mainly in the area of the Xujiahe formation as the research object, it accurately calculate the rock mechanics parameters, stress and formation three pressure, to give the safe density window of drilling fluid for the stability control of borehole, and to establish the stability analysis configuration of borehole and rock drill ability evaluation index. It also recommends an optional bit. Considering the advantages of logging method in the drilling engineering, such as continuity, high resolution and economy, we made lots of research on borehole stability in Jiulong Mountain, the main researches are as follows:(1) Based on the formation characteristics and rock core data of Jiulong Mountain to establish the pattern of porosity, permeability and saturation. At last, it makes interpretation of formation lithology profile, physical property profile.(2) By sonic logging data, it interpreted the rock mechanical parameters and crustal stress anisotropy. According to the rock mechanical test data, established Static Conversion formula for Young’s modulus and Poisson’s ratio, and set up rock mechanical parameters profile of Paleogene system and Cretaceous formation in designed area.(3) It optimizes the pattern to calculate the crustal stress, formation pressure, caving pressure and fracture pressure, and finally establishes their profile and analyses the longitudinal distribution characteristic.(4) Combined with the rock mechanics, crustal stress and formation pressure, caving pressure and fracture pressure profile, according to Mohr-Coulomb yield criterion, started from borehole stability to analyze the mechanism of borehole collapse and mud loss in the clastic rock formation. Furthermore, based on the logging data to identify the easily borehole collapse and mud loss formation. I set up the security mud density window.(5) According to the optimized model is established wellbore stability evaluation method for the Jiulong Mountain region; above all, Based on above researches, a evaluation software of borehole stability based on VB is programmed specific for Jiulong Mountain by virtue of Forward.net platform. Fortran programming language.Based on above researches, it gets the logging evaluation methods and techniques of the wellbore stability. From the area the data of many wells processing results, it is good effect. Considered the approved results of well-logging data processing, it has an important guiding function in drilling engineering design and construction.