Data Format


The strong-motion data, processed by the IES, provides  a uniform file format, with one file for each recording station. Each file contains a header section before the set of acceleration values.  The header is designed to provide the user with information about earthquake and the recording station. It includes a station name, followed by 40 integer variables. These integer variables represent the triggered time (or starting time), earthquake location and magnitude, sampling rate, maximum acceleration of each component and station location. The header of the data files can be described as follows:

xxxx (xxxx represents the file's station code)

integer variables (10I8)

 variable   number 

  description

1 year
2 month
day
4 hour
5 minute
6 second
millisecond   (1000 should divide millisecond)  
8  
9 starting time in second for SMART1 data  (1000 should divide starting time)  
10  
11-13 

Earthquake longitude in degree, minute and second

[note]: 10 should divide second of lon.

14-16

Earthquake latitude in degree, minute and second

[note]: 10 should divide second of lat.

17

Focal depth in km    [note]: 10 should divide  depth 

18

Earthquake local magnitude   [note]: 10 should divide magnitude

19

earthquake number

20  
21

series number

22  
23 

samples per second.

24  
25

total data points of each channel  

26-28

Maximum acceleration of vertical, east-west and north-south component in the unit of cm/sec2, respectively.

[note]: 1000 should divide the maximum acceleration.

29

pre-event memory in seconds

30  
31-33

Longitude of station location in degree, minute and second  

[note]: 1000 should divide second of lon.

34-36 

Latitude of station location in degree, minute and second 

[note]: 1000 should divide second of lat.

37

elevation in meters   [note]: 10 should divide the elevation  

38  
30  
39  
 40   

Integer parameters not mentioned here are for future structural collections; they are not used in any of the files in the current collection.  

Acceleration values (8F10.3)  

Using this format and taking into account the header included in each file-records it would be easy to read the time histories.

Example of data-file format:

[Header section]

JUN-KUNG MARBLE PLANT (station code)

Integer variables (10I8)

1990   12       13       5        34          31     470          0       0      0

 121   32     402      23       48        228         5         45      1       0

 164     0     200       0   12288      2072    3994    3387     15     0

 121    37   4700      24        1       1270      238         0       0      0

Triggered time (GMT): 12/13/1990 5:34:31.470 (integer parameters 1-7)

Epicenter: 121-32’40.2”E (integer parameters 11-13), 23-48’22.8”N (integer parameters 14-16)

Focal depth: 0.5 km (integer parameter 17)

Local magnitude: 4.5 (integer parameter 18)

Event number: 1 (integer parameter 19)

Series number: 164 (integer parameter 21)

Sampling rate: 200 samples per second (integer parameter 23)

Total number of data points: 12288 (integer parameter 25)

Maximum acceleration of vertical component: 2.702 cm/sec2 (integer parameter 26)

Maximum acceleration of east-west component: 3.994 cm/sec2 (integer parameter 27)

Maximum acceleration of north-south component: 3.387 cm/sec2 (integer parameter 28)

Pre-event memory: 15 seconds (integer parameter 29)

Station location: 121-37’4.70”E (integer parameters 31-33), 24-1’1.27”N (integer parameters 34-36)

Station elevation: 23.8 meters (integer parameter 37)

[Data section]: 8F10.3

[vertical component]

.082    .022   -.037   -.037   .022   .022   .202   .142

.082    .022   .022    .082   .142   .022   -.157   .022

.202    .082   .022   -.157   -.037   .082   .082   .022

[east-west component]

-.095   -.140   -.118   -.081   -.053   -.017    .010   .015

 .105    .062   .015   -.002   -.011   -.044   -.101   -.156

-.045    .019   .072    .118    .163    .203     .198     .137

[north-south component]

-.032   -.013    .027   -.006   -.073   -.075   -.062   -.103

-.011   -.046   -.055   -.022   -.013    .010    .102    .171

-.037   -.056   -.105   -.175   -.197   -.148   -.091   -.082