陇东地区三压力剖面和压裂高度测井预测研究

发布时间：2018-03-24 03:06

本文选题：陇东地区　切入点：岩石力学参数　出处：《西南石油大学》2015年硕士论文

【摘要】：鄂尔多斯盆地陇东地区古生界二叠系气藏埋藏较深,地质情况复杂,为典型的低孔、低渗、低压油气臧。钻井过程中经常发生井眼崩落与坍塌等井下事故,为了防止井壁失稳,确保安全钻进,选择合理的泥浆密度窗口就显得非常重要。另外,工区内大部分井自然产能较低,必须通过压裂改造措施方能获得工业产能。目前,陇东地区积累了大量的常规测井和偶极横波测井资料,充分利用测井资料可以准确地计算岩石力学参数、地应力和地层三压力及预测储层压裂缝参数等,这对优质高效安全钻井和采油工程具有重要的指导意义。本文以陇东地区上古生界二叠系石盒子组盒8段和山西组山1段气藏为研究对象,以弹性力学、岩石力学和压裂改造机理为理论基础,重点开展了五个方面的研究工作：①声波时差提取和岩石力学参数的测井计算；②地应力、地层三压力的计算及剖面建立；③储层压裂缝的测井预测方法研究；④压前预测与压后结果的测井对比分析；⑤优化编程及多井资料分析处理。通过以上工作,取得了以下主要研究成果和认识： (1)整理分析了工区岩石力学、钻井、地质、测井数据,从偶极横波测井资料中提取纵横波时差,归纳了岩石力学参数计算方法并建立了其动静态转换关系,获得了工区岩石力学特性剖面； (2)针对陇东地区气层“三低”特征,采用改进的地应力计算模型和优选的地层三压力计算公式,建立了地应力和地层三压力剖面并确定了合理的钻井液密度窗口； (3)优选了水力压裂缝高和缝宽预测模型,并探索了压裂缝缝长的测井预测方法,将预测结果同压后结果及FracproPT模拟结果对比分析,准确地评价压裂增产效果； (4)基于Forward.NET解释平台,编制了地应力、地层三压力计算和水力压裂缝延伸预测程序,处理了多口井资料,建立了5口井的岩石力学参数、地应力和地层三压力剖面,给出了目的层段的钻井液密度窗口,并预测对比了口井的裂缝扩展情况。通过上述研究,建立了套利用测井资料计算地应力、地层三压力和压裂缝延伸预测的方法和技术,可确定合理钻井液密度窗口并预测压裂缝延伸情况,处理结果合理可靠,与常用的测井解释和压裂预测软件具有良好的可比性。
[Abstract]:Permian gas reservoirs of the Paleozoic in Longdong area of Ordos Basin are deeply buried and complicated in geological conditions. They are typical low porosity, low permeability and low pressure oil and gas reservoirs. Borehole caving and collapse and other downhole accidents often occur during drilling, in order to prevent wellbore instability. To ensure safe drilling, it is very important to select a reasonable mud density window. In addition, the natural productivity of most wells in the working area is low, and only through fracturing measures can industrial production be obtained. A large amount of conventional logging and dipole shear wave logging data have been accumulated in Longdong area, which can accurately calculate rock mechanics parameters, ground stress and formation three pressures, and predict reservoir fracturing parameters, etc. It has important guiding significance for high-quality and high-efficient and safe drilling and oil recovery engineering. In this paper, the gas reservoirs of the Upper Paleozoic Permian Shihezi formation No. 8 and Shanxi formation Shan 1 are taken as the research objects, and the theory of elasticity, rock mechanics and fracturing mechanism are taken as the theoretical basis. Five aspects of research work have been carried out emphatically, namely, extracting the acoustic time difference from 1 to 1 and logging the rock mechanics parameters to calculate the in-situ stress. The calculation of formation three pressure and the Establishment of profile the logging Prediction method for the pressure fracture of the reservoir No. 3; A study on the log correlation analysis of the pre-pressure-prediction and post-fracturing results of No. 4 reservoir A _ (5) optimized programming and multi-well data analysis and processing. The following main research findings and understandings have been achieved:. 1) the rock mechanics, drilling, geology and logging data in the working area are analyzed, the P-S wave time difference is extracted from the dipole shear wave logging data, the calculation method of rock mechanics parameters is summarized and the dynamic and static transformation relations are established. The rock mechanical characteristic profile of the working area is obtained. (2) in view of the "three low" characteristics of gas reservoir in east Gansu, using the improved calculation model of in-situ stress and the optimum formula of three pressures of formation, the section of ground stress and formation three pressure is established and the reasonable window of drilling fluid density is determined. The prediction model of hydraulic pressure fracture height and fracture width is selected, and the logging prediction method of fracturing fracture length is explored. The results after same pressure and FracproPT simulation results are compared and analyzed to evaluate the effect of fracturing production increase accurately. (4) based on the Forward.NET interpretation platform, a program for prediction of in-situ stress, formation three pressures and hydrostatic fracture extension is developed. The data of multiple wells are processed, and the rock mechanics parameters, in-situ stress and formation three pressure profiles of five wells are established. The drilling fluid density window of the target interval is given, and the fracture propagation of the well is predicted and compared. Through the above research, the method and technology of calculating ground stress, formation three pressure and fracturing extension with well logging data are established. The reasonable drilling fluid density window can be determined and the fracturing extension can be predicted, and the treatment result is reasonable and reliable. It has good comparability with the commonly used well logging interpretation and fracturing prediction software.
【学位授予单位】：西南石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE31;P631.81

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