Experiment p4581
This is a run w/ Glass beads sheared in the grooved steel forcing blocks. Acoustic data are passive. See runsheet for details.

Mechanical Data

See links below for mechanical data, Acoustic data and instructions for using them.

The .txt file contains the acquisition parameters and data such as: shear stress, normal stress, shear displacement, normal load displacement, etc.

p4581_data.txt (10 Mb) Mechanical Data in ASCII format after applying calibrations and removing offset. Cols are labeled


p4581_runsheet.pdf Run Sheet for this experiment


Acoustic Data

plotacousticdata.m MATLAB script to plot the acoustic data:


You will need the following items in order to load and plot the data: Continuous acoustic data (below as a tar file), .mat files, acoustic time vector, ts_adjusted, and MATLAB scripts.

Download the .ac files,mat file, acoustic time vector and MATLAB scripts from the links here

Make sure to add the .ac and .mat files to your PATH in MATLAB.

Run plotacousticdata.m to plot the acoustic data (Amplitude vs. Time) for a single channel.

The .ac files contain the raw continuous time series data. Acoustic data are recorded continuously at 4 MHz throughout the experiment from a 15-bit data acquisition system.

The raw amplitudes inside the .ac files are in units of bits.

Each .ac file is ~ 20 MB. They are all in a tar file. You will need many gigabytes of disc space.

The p****.mat file contains the data acquisition parameters, such as sampling rate, number of channels, ..etc.



Matlab scripts and sync
ACTimeVector_4581.mat (17 MB)


p4581_AE.mat


Acoustics files
p4581acfiles.tar (55 GB) 2506 files


These .tdms files contain the raw continuous time series data. Acoustic data are recorded continuously at 40 kHz from an Accelerometer.
The ReadTDMS.txt file contains a few lines of code that will enable you to load/plot the acoustic data in Python.
For this experiment, large acoustic impulses were sent throughout the experiment from a large pizeoceramic disk (see Johson et al. 2008). The impulses can be found under the Acc variable in the mechanical data file. Similarly, these pulses are recorded on the accelerometer and can be seen when plotting the acoustic data.

ReadTDMS.txt MATLAB script to read acoustic files

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Data from this experiment are report in these two papers and others: Lyu, Z., Riviere, J., Yang, Q., and C. Marone, On the mechanics of granular shear: the effect of normal stress and layer thickness on stick-slip properties, Tectonophysics, 10.1016/j.tecto.2019.04.010, 2019.
Jasperson, H., Bolton, D. C., Johnson, P., Guyer, R., Marone, C., & de Hoop, M. V. (2021). Attention network forecasts time-to-failure in laboratory shear experiments. Journal of Geophysical Research: Solid Earth, 126, e2021JB022195. https://doi. org/10.1029/2021JB022195