In situ SEM fracture test of micro cantilever beams in shale samples

1. Sample information Two shale samples are from the Yanchang Formation (representative terrestrial shale formation), Ordos Basin, and the Longmaxi Formation (representative marine shale formation), Sichuan Basin, respectively. 2. Test area description A total of six test areas are selected. Test areas in the terrestrial shale sample are named T1, T2, and T3 respectively. Test areas in the marine shale sample are named M1, M2, and M3, respectively. Each test area contains a organic matter particle, and the organic type of each particle is determined through geochemical analysis: (1) T1: Inertinite; (2) T2: Vitrinite; (3) T3: Vitrinite; (4) M1: Bitumen; (5) M2: Bitumen; (6) M3: Bitumen. Micro cantilever beams are fabricated in each test area by using Xe PFIB (Helios G4 PFIB, Thermo Fisher). Organic matter particle is placed at the fixed end of the cantilever beam. 3. In situ SEM fracture test Micro cantilever beams are loaded by an in situ mechanical test device (PI88, Hysitron) in an ESEM (Quanta 200F, FEI). A flat diamond indenter with a diameter of 10 μm is placed at the free end of micro cantilever beam. The loading rate is 15 nm/s. Side-by-side videos and load and displacement curves are provided.1. 样品信息 本次实验共采集两块页岩样品，分别取自鄂尔多斯盆地延长组（典型陆相页岩地层）与四川盆地龙马溪组（典型海相页岩地层）。 2. 测试区域概况 共选取6个测试区域：陆相页岩样品对应的测试区域依次编号为T1、T2、T3，海相页岩样品对应的测试区域依次编号为M1、M2、M3。 每个测试区域均包含一块有机质颗粒，通过地球化学分析确定各颗粒的有机质类型： (1) T1：惰质组；(2) T2：镜质组；(3) T3：镜质组；(4) M1：沥青质；(5) M2：沥青质；(6) M3：沥青质。 采用氙气聚焦离子束（Xe PFIB，Helios G4 PFIB，赛默飞世尔科技（Thermo Fisher））在各测试区域制备微悬臂梁，并将有机质颗粒安置于悬臂梁的固定端。 3. 原位扫描电镜断裂测试 在环境扫描电子显微镜（ESEM，Quanta 200F，FEI公司）腔室内，借助原位力学测试装置（PI88，海思创（Hysitron））对微悬臂梁施加载荷。将直径为10 μm的扁平金刚石压头安装于微悬臂梁的自由端，加载速率设定为15 nm/s。本数据集同步提供配套测试视频及载荷-位移曲线数据。