P-wave velocity and attenuation (1/Q) data of water-saturated sand pack (from dry to full saturation) at 10 kilohertz frequency measured using an acoustic pulse tube under 10 MPa effective pressure

The data comprise P-wave velocity and attenuation (1/Q) measurements of water-saturated sand packs (four samples) across saturation levels, from dry to fully saturated. Using an acoustic pulse tube, measurements were recorded in the sonic frequency range (1-20 kHz, centred at 10 kHz) under 10 MPa effective pressure with atmospheric pore pressure. Data were collected in the Pulse Tube Laboratories at the National Oceanography Centre (NOC), Southampton, between March 2022 and January 2023, funded by the Natural Environment Research Council (NERC Grant NE/J020753/1), and primarily collected and analysed by Hanif Sutiyoso (University of Southampton). The experiment aimed to fill gaps in sonic frequency measurements of sediments across saturation states, providing a spectrum of water/gas saturation rather than a single value. This dataset is valuable for researchers analysing saturated sediments and is directly comparable to sonic well-logging field data due to its frequency range. The full dataset has been published at https://doi.org/10.1111/1365-2478.13607.
The method involved measuring time series of signal amplitude from four samples (A to D) inside a 4.5 m water-filled acoustic pulse tube, which allows plane wave propagation in the sediment-jacketed samples. Time-domain data were transformed into the frequency domain using Fast Fourier Transform (FFT) and deconvolved with the chirp source signal to obtain the impulse response. Nonlinear inversion was used to minimize an objective function derived from initial time-domain estimates, determining the sample's complex velocity and attenuation (1/Q).

本数据集包含四个水饱和砂样在不同饱和度水平（从干燥到完全饱和）下的纵波速度及衰减（1/Q）测量数据。研究采用声波脉冲管，在10兆帕有效压力与大气压孔隙压力条件下，于声波频率范围（1-20 kHz，中心频率10 kHz）内记录测量数据。数据采集于2022年3月至2023年1月期间，地点为南安普敦国家海洋学中心（National Oceanography Centre, NOC）的脉冲管实验室，由自然环境研究委员会资助（NERC Grant NE/J020753/1），主要采集与分析工作由南安普敦大学的Hanif Sutiyoso完成。本实验旨在填补不同饱和状态下沉积物声波频率测量的空白，提供水/气饱和度谱而非单一数值。该数据集对分析饱和沉积物的研究人员具有重要价值，且因其频率范围可直接与声波测井现场数据对比。完整数据集已发表于https://doi.org/10.1111/1365-2478.13607。
研究方法包括在4.5米充水声波脉冲管内测量四个样本（A至D）的信号振幅时间序列，该脉冲管允许平面波在包裹沉积物的样本中传播。时域数据通过快速傅里叶变换（FFT）转换至频域，并与线性调频源信号解卷积以获得脉冲响应。通过非线性反演最小化由初始时域估计推导的目标函数，以确定样本的复速度及衰减（1/Q）。