Shear strength (handheld penetrometer) from IODP Hole 386-M0091A

Shear strength from handheld penetrometer of the above given hole of International Ocean Discovery Program (IODP) Expedition 386 (Japan Trench Paleoseismology). This dataset was obtained at the end of the core processing workflow during the third phase (Personal Sampling Party, PSP) of expedition 386, which took place between 2022-11-15 – 2022-11-30 onboard D/V Chikyu. Measurements were performed on the work halves of core sections using a handheld (pocket) penetrometer equipped with a 10 mm diameter tip. The tip was pushed 6.3 mm perpendicular to the split core surface with the measuring pin downward until the groove marked on the tip was even with the level of the core surface. The resulting resistance (compressive strength) was read from the device and used to calculate undrained shear strength. At each measurement depth, three measurements were conducted and the resulting undrained shear strength averaged. In the case of major discrepancies between the three measurements, the team verified the results by repeating the measurements.For further methodological information see methods chapter in Strasser, M. et al., 2023 https://doi.org/10.14379/iodp.proc.386.102.2023

本数据集为国际大洋发现计划（International Ocean Discovery Program, IODP）386航次（日本海沟古地震学研究）上述钻孔的手持贯入仪（handheld penetrometer）剪切强度数据。该数据集采集于386航次第三阶段——个人采样队（Personal Sampling Party, PSP）的岩芯处理流程末期，此阶段航次于2022年11月15日至2022年11月30日期间在“地球号”（D/V Chikyu）钻探船上开展。研究人员采用配备直径10 mm探头的手持（袖珍）贯入仪，在岩芯段劈分后的工作半块上开展测量：将测量针朝下，使探头垂直于劈分后的岩芯表面推进6.3 mm，直至探头上的凹槽与岩芯表面齐平，此时读取设备显示的阻力（抗压强度），并据此计算不排水剪切强度（undrained shear strength）。每个测量深度处均开展三次测量，最终取三次不排水剪切强度的平均值；若三次测量结果存在显著偏差，则由团队重复测量以验证结果。如需进一步了解方法细节，请参阅Strasser M.等人2023年发表的方法章节，链接：https://doi.org/10.14379/iodp.proc.386.102.2023