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 |
| 3 | day |
| 4 | hour |
| 5 | minute |
| 6 | second |
| 7 | 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 |
| 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 [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 |
| 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