Access of Guerrero data

 

By following the link to Chronological Table of All Accelerograms , you will open a file that contains (or will soon contain) links to all data gathered by the Guerrero accelerograph network since 1985.  Should you use these data, we request that you cite the following paper which describes the Guerrero network:

Anderson, J. G., J. N. Brune, J. Prince, R. Quaas, S. K. Singh, D. Almora, P. Bodin, M. Onate, R. Vazquez and J. M. Velasco (1994).  The Guerrero accelerograph network, Geofisica Internacional 33, No. 3, 341-371.

We also request that you cite the appropriate data report, many of which are posted on this web site.

The Chronological Table of All Accelerograms  is a spreadsheet created by Microsoft Excel.  Once you have downloaded the table onto your computer, it will be possible for you to sort it according to your interest.

The table is sorted in chronological order.  The first column links you to an accelerogram in the format used uniformly for Mexican strong motion data.  This has a very complete, informative header.  Most of the rest of the columns in the Chronological Table of All Accelerograms, including magnitude and location of the earthquake, contain data drawn from this header. 

The second column links you to the same accelerogram in what we call a “Matlab-friendly format”.  This is a data file which can be loaded into Matlab (e.g. “load ATYC8509191.dat”), yielding a matrix with dimension  (n x 4), where n is the number of data.  The first column is the time after trigger time, the second is the acceleration in the east direction, the third is acceleration in the north direction, and the fourth is acceleration in the up direction.

Subsequent columns in the Chronological Table of All Accelerograms  are:

1.     (A) Link to data in original Mexican format

2.     (B) Link to data in Matlab-friendly format, as described above.

3.     (C) Station code

4.     (D) Event time: year

5.     (E) Month

6.     (F) Day

7.     (G) Hour

8.     (H) Minute

9.     (I) Second

10.  (J) Station latitude

11. (K) Station longitude

12. (L) Event depth

13. (M) Event magnitude (generally from Mexican seismic network)

14. (N) Event latitude

15. (O) Event longitude

16. (P) Station trigger time: hour

17. (Q) Minute

18. (R) Second

19. (S) Record statistics: sample rate (per second)

20. (T) Number of samples

21. (U) Duration of the seismogram

22. (V) Peak acceleration: east

23. (W) Peak acceleration: north

24. (X) Peak acceleration: up

 

Note: the following parameters are determined automatically by the program and in most cases are not reviewed. They are advisory only.

25. (Y) SA (absolute acceleration, 5% damping, 0.2 s period): east

26. (Z) SA (absolute acceleration, 5% damping, 0.2 s period): north

27. (AA) SA (absolute acceleration, 5% damping, 0.2 s period): up

28. (AB) SA (absolute acceleration, 5% damping, 1.0 s period): east

29. (AC) SA (absolute acceleration, 5% damping, 1.0 s period): north

30. (AD) SA (absolute acceleration, 5% damping, 1.0 s period): up

31. (AE) Epicentral distance, or 25 km if the earthquake is not located

32. (AF) ML, assuming above epicentral distance

33.  (AG). Ignore

34.  (AH) P-wave arrival time on the record, relative to start time. Set to zero if start of phase is not recorded.

35. (AI) S-wave arrival time on the record, relative to start time.

36. (AJ) Completeness code. 

1=complete P and S wave.

2=trigger misses the start of the P-wave.  S-wave is complete.

3=start of S-wave is not recorded, but peak of S-wave probably is recorded.

4=Not clear if S-wave is complete enough to recover peak acceleration.  Also assigned to seismograms with low amplitude, where the discretization of the analog-to-digital converter is obvious, implying that the uncertainty in the peak acceleration in the S-wave is large compared to the digitization interval.