Joseph P. Vantassel, jpvantassel.com
hvsrpy
is an open-source Python package for performing horizontal-to-vertical
spectral ratio (HVSR) processing of microtremor and earthquake recordings.
hvsrpy
was developed by Joseph P. Vantassel
with contributions from Dana M. Brannon under the supervision of Professor
Brady R. Cox at The University of Texas at Austin. hvsrpy continues to be
developed and maintained by Joseph P. Vantassel and his research group at Virginia Tech.
If you use hvsrpy
in your research or consulting, we ask you please cite the
following:
Joseph Vantassel. (2020). jpvantassel/hvsrpy: latest (Concept). Zenodo. http://doi.org/10.5281/zenodo.3666956
Note: For software, version specific citations should be preferred to
general concept citations, such as that listed above. To generate a version
specific citation for hvsrpy
, please use the citation tool on the hvsrpy
archive.
hvsrpy
implements the work of many others. Therefore we strongly encourage
users to cite the original work alongside hvsrpy
. Below we list key features
and their associated citation.
Lognormal statistics and fully-automated frequency-domain window-rejection algorithm.
Cox, B. R., Cheng, T., Vantassel, J. P., & Manuel, L. (2020). "A statistical representation and frequency-domain window-rejection algorithm for single-station HVSR measurements. Geophysical Journal International, 221(3), 2170–2183. https://doi.org/10.1093/gji/ggaa119
Statistical approach to incorporate azimuthal variability.
Cheng, T., Cox, B. R., Vantassel, J. P., and Manuel, L. (2020). "A statistical approach to account for azimuthal variability in single-station HVSR measurements." Geophysical Journal International, 223(2), 1040–1053. https://doi.org/10.1093/gji/ggaa342
Statistical approach to incorporate spatial variability.
Cheng, T., Hallal, M. M., Vantassel, J. P., and Cox, B. R., (2021). "Estimating Unbiased Statistics for Fundamental Site Frequency Using Spatially Distributed HVSR Measurements and Voronoi Tessellation. J. Geotech. Geoenviron. Eng. 147, 04021068. https://doi.org/10.1061/(ASCE)GT.1943-5606.0002551
SESAME clarity and reliability criteria for microtremor HVSR.
SESAME. (2004). Guidelines for the Implementation of the H/V Spectral Ratio Technique on Ambient Vibrations Measurements, Processing, and Interpretation. European Commission - Research General Directorate, 62, European Commission - Research General Directorate.
Computation of HVSR under the diffuse field assumption.
Sánchez-Sesma, F.J., Rodríguez, M., Iturrarán-Viveros, U., Luzón, F., Campillo, M., Margerin, L., García-Jerez, A., Suarez, M., Santoyo, M.A., Rodríguez-Castellanos, A. (2011). A theory for microtremor H/V spectral ratio: application for a layered medium: Theory for microtremor H/V spectral ratio. Geophysical Journal International 186, 221–225. https://doi.org/10.1111/j.1365-246X.2011.05064.x
Power spectral density (PSD) calculation.
Welch, P., (1967). The use of fast Fourier transform for the estimation of power spectra: a method based on time averaging over short, modified periodograms. IEEE Transactions on audio and electroacoustics, 15(2), pp.70-73.
New high noise model (NHNM) and new low noise model (NLNM).
Peterson, J., (1993). Observation and Modeling of Seismic Background Noise (Open-File Report No. 93–322). U.S. Geologic Survey, Albuquerque, New Mexico.
hvsrpy
would not exist without the help of many others. As a
display of our gratitude, we thank them individually
here.
hvsrpy
contains features not currently available in any other commercial or
open-source software, including:
fn
) so the uncertainty in fn
can be represented consistently
in frequency and period.fn
that incorporates azimuthal
variability.hvsrpy
when considering the geometric-mean of the horizontal componentsLognormal Median | Lognormal Standard Deviation | |
---|---|---|
Site Frequency, fn | 0.67 | 0.09 |
Site Period, Tn | 1.50 | 0.09 |
hvsrpy
when considering azimuthal variabilityLognormal Median | Lognormal Standard Deviation | |
---|---|---|
Site Frequency, fn,az | 0.67 | 0.07 |
Site Period, Tn,az | 1.50 | 0.07 |
hvsrpy
when considering spatial variabilityLognormal Median | Lognormal Standard Deviation | |
---|---|---|
Site Frequency, fn,xy | 0.58 | 0.15 |
Site Period, Tn,xy | 1.74 | 0.15 |
Some of the functionality available in hvsrpy
overlaps with the popular
open-source software geopsy
. Therefore, to encourage standardization, wherever
their functionality coincides we have sought to ensure consistency. Two such
comparisons are shown below. One for a single time window (top) and one for
multiple time windows (bottom). Additional examples are provided at the end of
this document. Additional examples and the code to reproduce all of the
examples shown are provided in the
gallery.
If you do not have Python 3.8 or later installed, you will need to do so. A detailed set of instructions can be found here.
If you have not installed hvsrpy
previously, you can install it with
pip
via the command pip install hvsrpy
.
If you are not familiar with pip
, a useful tutorial can be found
here. If you have
an earlier version and would like to upgrade to the latest version of hvsrpy
use pip install hvsrpy --upgrade
.
Confirm that hvsrpy
has installed/updated successfully by examining the
last few lines of the text displayed in the console.
Download the contents of the examples directory to any location of your choice.
Launch the Jupyter notebook (example_mhvsr_traditional.ipynb
) in the examples
directory for a no-coding-required introduction to the basics of the hvsrpy
package. If you have not installed Jupyter Lab
, detailed instructions can be
found here.
Continue to explore the other example notebooks provided. Note that each
example notebook seeks to highlight one or two key features of hvsrpy
and
it may be helpful to combine multiple components together to build
a custom workflow, this is highly encouraged.
Enjoy!
More information regarding HVSR processing and hvsrpy
can be found
here
and in the softwares documentation
here.
The examples in this section use the same settings applied to different noise records. The settings are provided in the Settings section and the name of each file is provided above the corresponding figure in the Results section. The noise records (i.e., .miniseed files) are provided in the examples directory and also as part of a large published data set (Cox and Vantassel, 2018).
File Name: _UT.STN11.A2C50.miniseed
File Name: _UT.STN11.A2C150.miniseed
File Name: _UT.STN12.A2C50.miniseed
File Name: _UT.STN12.A2C150.miniseed
The examples in this section apply different settings to the same noise record (_UT.STN11.A2C50.miniseed). For brevity, the default settings are listed in the Default Settings section, with only the variations from these settings noted for each example.
Default Case: No variation from those settings listed above.
Window Length: 120 seconds.
Cosine Taper Width: 20 % (i.e., 10 % in Geopsy)
Cosine Taper Width: 0.2 % (i.e., 0.1 % in Geopsy)
Konno and Ohmachi Smoothing Coefficient: 10
Konno and Ohmachi Smoothing Coefficient: 80
Number of Points: 512
Number of Points: 4096