The influence of heterogeneity of lacustrine shale facies on rock mechanical properties and brittleness: a case study of Jurassic lacustrine shale reservoirs in Northeast Sichuan Basin - Zhao, Haibo; Yin, Shujun; Yang, Xuefeng; Yan, Weilin; Bi, Guangwu; Zhang, Jianliang; Xing, Zimeng (Frontiers in Earth Science, 2025)