| Title | Understanding the creep behavior of shale via nano-DMA method |
| Authors | Liu, Kouqi Jin, Zhijun Zeng, Lianbo Ostadhassan, Mehdi Xu, Xiaomeng |
| Affiliation | Peking Univ, Inst Energy, Beijing 100871, Peoples R China China Univ Petr, State Key Lab Petr Resources & Prospecting, Beijing 102249, Peoples R China China Univ Petr, Coll Geosci, Beijing 102249, Peoples R China Northeast Petr Univ, Key Lab Continental Shale Hydrocarbon Accumulat &, Minist Educ, Daqing 163318, Peoples R China Univ Kiel, Inst Geosci Marine & Land Geomech & Geotecton, D-24118 Kiel, Germany China Jiliang Univ, Coll Qual & Safety Engn, Hangzhou 310018, Peoples R China |
| Keywords | DYNAMIC-MECHANICAL ANALYSIS NANOINDENTATION |
| Issue Date | Nov-2021 |
| Publisher | ENERGY REPORTS |
| Abstract | Understanding the creep behavior of shale is essential to precisely predict borehole instability issues and model fracturing of unconventional shale reservoirs. In this study, the creep behavior of shale in micron scale is investigated by integrating the nano-dynamic mechanical analysis (nano-DMA) grid nanoindentation (15 x 15 indents) and data clustering techniques. The results showed that the creep displacement, the creep rate, and hardness, both can be related through a logarithmic function with creep time. Furthermore, contact creep modulus increased as the hardness or Young's modulus increased. The clustering analysis revealed that three separate phases are present in the samples where Phase 1(clay/organic matter) has the smallest contact creep modulus and Phase 3 (quartz) the largest. While creep is in progress, the creep displacement, hardness and contact creep modulus of all three phases obey the logarithmic function. Under the same creep time, reduction in the contact creep modulus of Phase 3 appears to be faster than Phase 1 while the creep rate of Phase 3 is much less than Phase 1. Ultimately, contact creep modulus is better correlated with hardness than Young's modulus. (C) 2021 The Authors. Published by Elsevier Ltd. |
| URI | http://hdl.handle.net/20.500.11897/636980 |
| ISSN | 2352-4847 |
| DOI | 10.1016/j.egyr.2021.10.099 |
| Indexed | SCI(E) |
| Appears in Collections: | 待认领 |
