P-wave velocity of discrete samples (DPW) from IODP Hole 386-M0081C

P-wave velocity data from discrete samples from the above given hole of International Ocean Discovery Program (IODP) Expedition 386 (Japan Trench Paleoseismology). During the onshore phase of expedition 386, which took place between 2022-02-14 – 2022-03-15 onboard D/V Chikyu, discrete samples for P-wave velocity measurements were taken from the work halves approx. every 2 meter down core using syringes with an inner diameter of 2 cm. Samples measured 2.5–3 cm long for a sample volume of ~10 cubic centimetres. Samples were then shipped to the European Petrophysics Consortium (EPC) laboratory at the University of Leicester (UK) for processing. Measurements were performed with a Geotek P-wave logger for discrete samples (PWL-D). Measurements were attempted for each sample, however, the unconsolidated lithology of some samples proved unsuitable for the instrument (e.g. too soupy or too friable to be placed between the transducers).Operator notes: Data from section numbers > 30 can be associated to a decrease in velocity values, this is likely due to cracks opening in the samples when applying pressure on it at the time of measurement (as observed by operators). For holes M0081E & F Sections 1-29 velocity values are overestimated due to an issue with the calibration.For further methodological information see methods chapter in Strasser, M. et al., 2023 https://doi.org/10.14379/iodp.proc.386.102.2023

本数据集包含国际大洋发现计划（International Ocean Discovery Program, IODP）386航次（日本海沟古地震科考）指定钻孔的离散样品P波速度实测数据。
该航次陆上作业阶段于2022年2月14日至2022年3月15日在“地球号”（D/V Chikyu）钻探船上开展，作业人员以内径2 cm的注射器，沿岩芯每约2米的间隔从岩芯工作半段中采集用于P波速度测量的离散样品。单份采集样品的长度为2.5–3 cm，体积约10立方厘米。
随后所有样品被运送至英国莱斯特大学欧洲岩石物理联盟（European Petrophysics Consortium, EPC）实验室开展预处理及测试。
本次测试采用Geotek离散样品P波速度测井仪（Geotek P-wave logger for discrete samples, PWL-D）完成。研究人员尝试对每份样品进行测量，但部分样品的未固结岩性不适用于该仪器——例如样品过于粘稠或过于松散，无法放置在换能器之间。
操作员备注：层段编号大于30的样品速度值存在偏低现象，这大概率是测量时施加压力导致样品内部产生裂隙所致（操作员现场观测所得）。对于M0081E与M0081F钻孔的1–29号层段，因校准问题导致速度值被高估。
如需获取详细实验方法信息，请参阅Strasser M.等（2023）发表的国际大洋发现计划386航次报告方法章节，链接：https://doi.org/10.14379/iodp.proc.386.102.2023