PGV to displacement

Technical Support
1

Hi all,

I’m trying to convert geophone data to find out the displacement from velocity. Ideally, integration of velocity would give displacement. Is there easy solution to do it? for python or Matlab? @iannesbitt

2

It’s not perfect, but the way I do it in rsudp is:

  1. deconvolve to velocity

    from obspy import read, read_inventory

inv = read_inventory('/path/to/resp.xml')  # (or use get_stations)
stream = read('/path/to/data.ms')          # (or use get_waveforms)

trace = stream.select(channel='*HZ')
sps = trace.stats.sampling_rate
trace.remove_response(inventory=inv,
                      pre_filt=[0.1, 0.6, 0.95*sps, sps],
                      output='VEL', water_level=4.5, taper=False)

  2. “integrate” (cumulatively sum) velocity values to get displacement

    import numpy as np
trace.data = np.cumsum(trace.data)  # end result is in meters

Note: see also info on get_stations() and get_waveforms()

3

Thank you @iannesbitt.

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