油气勘探领域微米CT实验关键技术探讨及应用

Discussion on key technologies in micro-CT experiments and their applications in oil and gas exploration

  • 摘要: 微米CT技术在油气田勘探与开发过程中已得到广泛应用,但关键控制参数、数据处理方法等环节尚未形成统一的规范,其数据的准确性和可比性仍受到较大影响。为系统研究微米CT实验参数对测试结果的影响,选取南海北部湾盆地和莺歌海盆地的7块典型样品,重点探讨检测分辨率、表征性体积单元大小及数据处理方式对实验结果的影响。研究结果表明:(1)固定的检测分辨率是确保数据可靠性的关键因素,对孔隙结构参数的提取及后续分析影响最为显著,应综合考虑样品尺寸和岩性特征等因素进行优化设置;(2)在表征砂岩样品孔隙度时,较大的体积单元能提高结果的准确性,而在构建孔隙网络模型时,表征性体积单元应不小于600体素×600体素×600体素,以确保网络模型的代表性;(3)采用分区间统计法计算孔隙直径(Φ)的累积体积频率,并绘制孔径分布曲线,同时使用体积法计算平均孔径,可更精确地表征岩石的孔隙结构特征。研究结果不仅为微米CT技术在油气勘探中的测试流程和应用提供了理论支撑,同时也为实验规范的制定提供了参考。

     

    Abstract: Micro-CT technology has been widely applied in oil and gas exploration and development. However, unified standards for key control parameters and data processing methods have yet to be established, significantly affecting data accuracy and comparability. To systematically study the impact of micro-CT experimental parameters on test results, seven representative samples from the Beibuwan Basin and the Yinggehai Basin in the South China Sea were used as the research subjects. The research focused on the impact of scanning resolution, representative volume element (RVE) size, and data processing methods on experimental outcomes. The findings indicated that: (1) A fixed scanning resolution is a key factor in ensuring data reliability, as it significantly affects the extraction of pore structure parameters and subsequent analysis. Resolution should be optimized considering sample size and lithological characteristics. (2) For characterizing the porosity of sandstone samples, better result accuracy can be achieved by increasing the RVE size. While constructing pore network models, the RVE size should be no smaller than 600×600×600 voxels to ensure model representativeness. (3) Use interval-based statistics to calculate the cumulative volume frequency of pore diameters (Φ), and plot the pore size distribution curves. Use the volumetric method to calculate the average pore diameter. These methods can provide a more accurate characterization of rock pore structure. The study offers theoretical support for the application and workflow optimization of micro-CT technology in oil and gas exploration, providing a reference for establishing experimental standards.

     

/

返回文章
返回