Xinjiang Oil & Gas ›› 2023, Vol. 19 ›› Issue (1): 57-64.DOI: 10.12388/j.issn.1673-2677.2023.01.009

• OIL AND GAS DEVELOPMENT • Previous Articles     Next Articles

Evaluation of Fracability of Heterogeneous Ultra-Heavy Oil Loose Sandstone Reservoirs

  

  1. 1.College of Artificial Intelligence,China University of Petroleum(Beijing),Changping 102249,Beijing,China; 2. College of Petroleum Engineering,China University of Petroleum(Beijing),Changping 102249,Beijing,China
  • Online:2023-03-06 Published:2023-03-20

非均质超稠油疏松砂岩储层可压性评价

  

  1. (1.中国石油大学(北京)人工智能学院,北京昌平 102249;2.中国石油大学(北京)石油工程学院,北京
    昌平 102249
  • 作者简介:张润雪(1996-),中国石油大学(北京)油气井工程专业在读硕士,目前从事超稠油储层非均质性和可压性方面的研究。(Tel)18101365887(E-mail)runxiaoxue123@163.com
  • 基金资助:

    国家自然科学基金“砾岩储层砾石-交界面-基质合压水力裂缝非平面扩展机制研究”(编号:42277122)

Abstract:

At present,there is no standard method for evaluating the fracability of ultra-heavy oil loose sandstone reservoirs in China. On the basis of the study exploring the fracability of heterogeneous ultra-heavy oil reservoirs in Fengcheng,Xinjiang,the Lorenz coefficient method was used to evaluate the heterogeneity of reservoirs and define the concept of fracability of ultra-heavy oil reservoirs. Multidimensional geological engineering parameters were selected as indicators to evaluate the fracability of heterogeneous ultra-heavy oil reservoirs in Fengcheng,Xinjiang,the gray correlation method was used to guide the establishment of the judgment matrix when selecting parameter weights,and the gray correlation-hierarchy analysis method was used to establish the fracability evaluation model of this type of reservoir. The fracability indexes of eight layers of two blocks of the Xinjiang Fengcheng Oilfield before reservoir stimulation were calculated,which showed that the reservoir fracability index is negatively correlated with heterogeneity. When the reservoir fracability index is greater than 0.7,the corresponding Lorenz coefficient is less than 0.5,and larger tensile dilatancy can be achieved through microfracturing reservoir stimulation. This fracability evaluation method can help assess the fracability of heterogeneous ultra-heavy oil reservoirs,which provides guidance for on-site microfracturing stimulation,and helps oilfields to improve the final oil recovery of wells.

Key words:

"> ultra-heavy oil reservoir, loose sandstone, fracability, multidimensional parameter, microfracturing

摘要:

目前国内针对超稠油疏松砂岩储层可压性尚无统一的评价方法。在研究新疆风城非均质超稠油储层可压性的基础上,用洛伦兹系数法评价储层的非均质性,定义超稠油储层可压性概念。选取多维地质工程参数作为评价新疆风城非均质超稠油储层可压性的指标,使用灰色关联法指导建立参数权重选取时的判断矩阵,采用灰色关联-层次分析法建立该类储层的可压性评价模型。计算新疆风城油田两个区块8个层段储层改造前的可压性系数,结果显示储层可压性与非均质性具有负相关关系。当储层可压性系数大于0.7时,对应洛伦兹系数小于0.5,通过微压裂储层改造后能获得较大的张性扩容量。该可压性评价方法能够判断非均质超稠油储层的可压性优劣,对现场微压裂改造具有一定的指导意义,帮助油田现场提高油井最终采收率。

关键词:

超稠油储层, 疏松砂岩, 可压性, 多维参数, 微压裂