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Long range shock waves from a large explosion underwater: experiment and data
7. The data
This chapter describes the data which has been acquired, with particular
emphasis on that from the instrumentation at sea.
A list of sites at which the larger of the two explosions is known to
have been recorded is given in Appendix E and illustrated on the map in
Fig. 7.1. The list includes the sites at sea, and BGS temporary and
permanent sites covering the UK and Eire. In addition to the permanent
land stations of the various BGS networks and University arrays, a number
of temporary stations were deployed for the event by other organisations
including The Dublin Institute of Advanced Studies (72 stations),
University of Hull (5 stations) and Glasgow University (2 stations).
This report concentrates on the data from the sea bed instrumentation
along the great circle path from the shot point to Tentsmuir A (Fig. 2.2).
These comprise the PUSSes and the BGS Sea Bottom Package and the land
station at Tentsmuir. These files were subjected to pre-treatment in
order that the maximum amount of data could be recovered, and that the
final data set files should all be in the same format.
7.1 DATA FORMAT
The format selected for the data files consists of a four line header
block containing information on:
( 1) The fi lename
(2) The source explosion
(3) The station, channel and instrument
(4) The data, e.g. sampling rate, units etc.
followed by the data values for a single channel in double precision fixed
format in order that the full number of significant figures could be
preserved for data from all sources. An example is given in Table 7.1.
The header was designed to contain all the information required by
standard time series analysis programs.
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