Seed2Cor

Parallel single component ambient noise correlation from SEED

Extract SAC & response from SEED
Remove instrument response
Temporal (1-bit, run-absolute-mean, cut events) & spectral (whiten) normalization
Cross/Auto-correlate & stack

Directory structures

input/: template files for input
src/: source code
tools/: auxiliary scripts

Usage

Dependencies

Currently tested on

RHEL (Red Hat Enterprise Linux): 6.9, 7.3
gcc: 6.1.0, 4.4.7 20120313 (Red Hat 4.4.7-18)
FFTW: 3.3.7, 3.3.4 (failed!), 3.2.3
rdseed 5.3.1
evalresp 3.3.3

Compile

$ cd src/
$ make

The output could be compared with src/make.log.

Input

parameters: processing parameters
- see input/parameters.lst for template
seed.lst: list of SEED files
- see input/seed.lst for template
- use tools/generate_seedlst.sh to generate

station.lst: list of stations

see input/station.lst for template
use tools/generate_stationlst.sh to generate

optional flag

0-N
For stations with same number n (except 0), do cc,
also do cc with group 0,
but do not do cc with other numbers.
For number 0, do cc with all other group,
but do not do cc with all other group 0 members.

Run

$ Seed2Cor parameter_file [nthreads]

A Python wrapper tools/s2c_wrapper.py with a YAML parameter file input/param.yml might be helpful.

Output

File Structure

yyyy.MMM/
- yyyy.MMM.dd/
- COR/: monthly correlations
  - STA/
    - COR_MASTER_SLAVE.SAC
- COR_D/: daily correlations
  - STA/
    - COR_MASTER_SLAVE_dd.SAC
- Cor_dayflag.lst: days if data available

SAC Header

KEVNM: source station
KSTNM: receiver station
USER0: # of days stacked

Attention

The temperal normalization method of 'earthquake cutting' has NOT been well tested. Use with caution!
The spectrum reshape function is currently removed from the code. (Smooth2() in Whiten.c does nothing)

Reference

Bensen, G. D., Ritzwoller, M. H., Barmin, M. P., Levshin, A. L., Lin, F., Moschetti, M. P., et al. (2007). Processing seismic ambient noise data to obtain reliable broad-band surface wave dispersion measurements. Geophysical Journal International, 169(3), 1239–1260.

Lin, F.-C., Ritzwoller, M. H., & Shen, W. (2011). On the reliability of attenuation measurements from ambient noise cross-correlations. Geophysical Research Letters, 38(11).

NoiseCIEI / Seed2Cor