Dataset for "Thermal Stressing of Volcanic Rock: Microcracking and Crack Closure Monitored through Acoustic Emission, Ultrasonic Velocity, and Thermal Expansion."

This README describes the contents of the dataset, split into P-wave velocity data (travel times, velocities, and raw signal waveforms), thermal expansion measurements, and acoustic emission monitoring data.Wave velocity dataCalculated velocitiesIn the folder /Acoustic velocity.For each experiment and heating/cooling cycle, the wave velocities are given in excel spreadsheets (e.g. EB_p_wave_data_cycle_1.xlsx). The columns contain the following data:* time: the time at which the measurement was made* TEMP: the furnace temperature* vp_cross_correlation: The P-wave velocity calculated using the cross-correlation method.Raw waveform dataThe raw waveform data is also provided for each heating/cooling cycle (e.g. EB_waveforms_cycle_1.csv). The CSV contains the text version of an array with shape (4001, N), where N is the number of measurements during a heating/cooling cycle. The first row of the file contains the times at which the measurement was made. The remaining 4000 rows of a column are the measured voltage values recorded at a 2 MHz sampling frequency.Thermal expansion dataIn the folder /Thermal expansionFor each of the three samples, there is an excel spreadsheet containing the following columns (e.g., Elongation_EB.xlsx).The sample elongation is measured over three heating and cooling cycles and the columns contain the following data:* Temp [°C]: sample temperature in degrees Celsius* Time/min: time elapsed in minutes* dL/Lo: change in length relative to initial lengthAcoustic emission (AE) monitoring dataIn the folder /Acoustic emissionsFor each experiment and heating/cooling cycle, the time and characteristics of each AE hit are given in excel spreadsheets (e.g. EB_AE_cycle_1.xlsx). The columns contain the following data:TIME: The time of the AE hit from the start of the experiment in seconds.RISE: The rise time from an AE signal’s first threshold crossing to its peak.COUN: The number of counts, or number of times the AE signal crosses the AE threshold.ENER: A measure of energy released during the AE event, equal to the integral of the voltagesignal over the duration of the AE hitDURATION: AE Duration is defined as the time from the first threshold crossing to the end of the last.AMP: The AE Amplitude is the maximum voltage (negative or posotive) during an AE hit (in dB).A-FRQ: The average frequency, equal to COUN / DURATION.RMS: The root mean square of the recorded voltage signal.ABS-ENERGY: The absolute energy of the AE signal, calculated as integral of the squared voltage waveform divided by the reference resistance (10 kohm).TEMP: The temperature at the time of the AE hitCUMABS-ENERGY: The cumulative absolute energy.CUMHITS: The cumulative number of AE hits