The laboratory characterization of tight rocks is essential for reliable rock physics analysis. In this study, combined laboratory experiments and computational calculations were applied to specimens from the Bakken Formation to examine the mechanical properties of the unconventional petroleum resource in different scales. Multistage compressive tests were conducted on core plugs with several loading-unloading cycles under different confining pressures. Microscale mechanical test, nanoindentation, were performed to measure microscale elastic properties. Additionally, a comparative study was included using homogenization upscaling methods to model the modulus of the macro-scale sample from nanoindentation measurements and rock mineralogy, respectively.

Results from the triaxial compressive tests showed nonlinear behavior for all samples and pronounced plastic deformation was observed during loading-unloading cycles when lower confining pressures were employed. Young's modulus increased with confining pressures increasing. The ultrasonic P- and S-wave velocities are sensitive to the changes of confining and differential stresses, which might be due to the open and closure of microcracks. Three mechanical phases can be found from nanoindentation results by deconvolution, and the average microscale Young's modulus obtained from nanoindentation tests showed a positive relationship with the theoretical Voigt and Reuss boundaries. The prediction of Young's modulus from mineral fractionand moduli information indicated a better agreement with laboratory data than the nanoindentation cluster dataset.

致密岩石的实验室表征对于可靠的岩石物理分析至关重要。在这项研究中，结合实验室实验和计算计算应用于巴肯组的标本，以检验不同规模非常规石油资源的力学性能。对岩心塞进行了多级压缩试验，并在不同的围压下进行了多次加载-卸载循环。进行微型机械测试，纳米压痕以测量微型弹性性能。此外，还包括使用均质化放大方法进行的对比研究，以分别根据纳米压痕测量和岩石矿物学对宏观样品的模量进行建模。

三轴压缩试验的结果表明，所有样品均表现出非线性行为，当采用较低的围压时，在装卸循环中观察到明显的塑性变形。杨氏模量随围压的增加而增加。超声波P-和S-波速对约束应力和微分应力的变化很敏感，这可能是由于微裂纹的打开和闭合所致。通过反卷积可以从纳米压痕结果中发现三个机械相，并且从纳米压痕测试获得的平均微尺度杨氏模量与理论Voigt和Reuss边界呈正相关。从矿物分数和模量信息预测杨氏模量表明，与纳米压痕簇数据集相比，与实验室数据具有更好的一致性。