The diametrical core deformation analysis (DCDA) method can determine the differential stress (ΔS = SH − Sh) by measuring the variability of the core diameters, where SH and Sh are the maximum and minimum horizontal stress applied. Rock mechanical properties and anisotropy of the core affect its credibility and accuracy, as well as the combination with the hydraulic fracturing (HF) method, but have not been systematically studied upon sufficient measured data yet. In this study, taking the 400 m depth Lianjiang (LJ) borehole as a case, we analyzed the effect of rock mechanical properties and core anisotropy on DCDA results through four rock experiment schemes, and further conducted a comparison with the corresponding HF results. The results indicate that the new scheme—measuring wave velocity in the linear stage of the conventional triaxial compression test, simulates the core in-situ conditions better and can reduce the potential effect of microcracks within the core on the DCDA method. The ΔS determined upon the conventional uniaxial compression test is the lowest value, while that upon the new test scheme is the largest value among the four schemes. Although the ΔS values determined using DCDA and HF methods mainly fall in comparable ranges in the LJ borehole, the values of the former are approximately 18%–58% larger than those of the latter, within the test depth. We considered that the large deviations between the DCDA and HF results mainly arise from the variation of the effect of the rock anisotropy at differenttest scales. It is recommended to conduct a careful estimation of the core anisotropy and borehole conditions when integrating DCDA and HF methods at great depths. This study provides a new understanding of the validity of the DCDA method, as well as its combination with HF, which supports its application in stress constraints at great depth.Highlights<UnorderedList Mark="Bullet"> <ItemContent> We proposed four rock mechanics experiment schemes to analyze the effect of rock mechanical properties on stress constraint using the DCDA method. </ItemContent> <ItemContent> The wave velocity test in the linear stage of the triaxial compression test improves the reliability of stress constraint using the DCDA method. </ItemContent> <ItemContent> The DCDA method provides larger differential stress magnitudes than the corresponding HF test. </ItemContent> <ItemContent> We discussed the reasons for the differences in stress determinations between DCDA and HF methods, and proposed conditions for jointly constraining stress. </ItemContent> </UnorderedList>

Comparison of In-Situ Stress Determination Using the Diametrical Core Deformation Analysis and Hydraulic Fracturing Methods: A Case Study in SE China

期刊论文
发表日期：

2026年1月13日

查看全文

Xianghui Qin,
Weiren Lin,
Chongyuan Zhang,
Zhigang Tao,
Zhihao Liang,
Manchao He

摘要

The diametrical core deformation analysis (DCDA) method can determine the differential stress (ΔS = S_H − S_h) by measuring the variability of the core diameters, where S_H and S_h are the maximum and minimum horizontal stress applied. Rock mechanical properties and anisotropy of the core affect its credibility and accuracy, as well as the combination with the hydraulic fracturing (HF) method, but have not been systematically studied upon sufficient measured data yet. In this study, taking the 400 m depth Lianjiang (LJ) borehole as a case, we analyzed the effect of rock mechanical properties and core anisotropy on DCDA results through four rock experiment schemes, and further conducted a comparison with the corresponding HF results. The results indicate that the new scheme—measuring wave velocity in the linear stage of the conventional triaxial compression test, simulates the core in-situ conditions better and can reduce the potential effect of microcracks within the core on the DCDA method. The ΔS determined upon the conventional uniaxial compression test is the lowest value, while that upon the new test scheme is the largest value among the four schemes. Although the ΔS values determined using DCDA and HF methods mainly fall in comparable ranges in the LJ borehole, the values of the former are approximately 18%–58% larger than those of the latter, within the test depth. We considered that the large deviations between the DCDA and HF results mainly arise from the variation of the effect of the rock anisotropy at differenttest scales. It is recommended to conduct a careful estimation of the core anisotropy and borehole conditions when integrating DCDA and HF methods at great depths. This study provides a new understanding of the validity of the DCDA method, as well as its combination with HF, which supports its application in stress constraints at great depth.

Highlights

We proposed four rock mechanics experiment schemes to analyze the effect of rock mechanical properties on stress constraint using the DCDA method.

The wave velocity test in the linear stage of the triaxial compression test improves the reliability of stress constraint using the DCDA method.

The DCDA method provides larger differential stress magnitudes than the corresponding HF test.

We discussed the reasons for the differences in stress determinations between DCDA and HF methods, and proposed conditions for jointly constraining stress.