08 Oct 2005 : GWA : Explanation for how to use datafiles.

Data from each node is located in a separate file.  Each file has a header
describing the data in the file.  Most of the important details concerning
the file including the length of the event, start and end times, and dynamic
ranges observed can be found in this header.

The most important piece of data not in the header are the column formats.
These should be in the header and will be soon but for the time being they
are not and so are described below.

1) For all motes EXCEPT 250 and 251 (i.e. all 2-channel nodes) data is in the
following format:

<GMT Seconds Since Jan 1 1970> <Seismometer Data> <Microphone Data>

Both the seismometer and the microphone data points have been normalized to
fall from (-1, 1) using the dynamic range of the ADC.

2) For motes 250 and 251 (i.e. all 4-channel nodes) data is in the following
format:

<GMT Seconds Since Jan 1 1970> <Seismometer Vertical Data> <Seismometer N-S
data> <Seismometer E-W data> <Microphone Data>

Normalization identical to above.

3) Data from nodes 9024, 9025 and 9026 was provided by Reftek 130 data loggers
attached to a broadband seismometer (3 channels) and a infrasonic microphone
(1 channel).

4) Locations of each station are indicated in the STATIONLOCATIONS.txt file
located in this directory.