.lsd file format

Keywords

Each line of a .lsd file consists of either a comment, or a keyword and its parameters.

A Keyword Line consist of several tokens (strings or numbers) that are separated by whitespace (the space character [ASCII 32] or Tab stops [ASCII 9]). The line begins with the Keyword itself, which may be followed by a Keyword Modifier and then a number of Keyword Parameters:

!Keyword !Modifier parameter parameter parameter

The Exclamation mark "!" is used to distinguish Keywords and Modifiers from parameters. The possible Modifiers and the allowed number of parameters depend on the Keyword.

A consequence of the use of whitespace as parameter separator are certain limitations to string parameters: only one string parameter per keyword is possible, since strings may consist of several words which are also separated by whitespace, and a string parameter also has to be the last parameter of a multi-parameter keyword.

A simple example is

!arrival !baz 40 45

where "arrival" is the keyword and "baz" is the modifier. "40 45" are numeric parameters. This example line defines some Back Aimzuith angle to be in the interval 40...45 (in implied units, see section on units in Tutorial).

Another example is

!station !start Klaus

Where "station" is the keyword, "start" is a modifier and "Klaus" is a string parameter. This example defines the name of a station to be "Klaus" and begins a station description block.

The following tables give a list of all Keywords, their Modifiers and the specified Parameters. (The sequence in which the two or three numbers that specify a value are given, is not relevant. See section on parameter model.)

List of all Keywords:

  1. station
  2. event
  3. arrival
keyword: station
Modifier Parameter Type Explanation
start station identifier string Station record start tag.
The parameter is an arbitrary string used to identify the station
end none - Travel Time record end tag
lon value numeric Station longitude
lat value numeric Station latitude
elev value numeric Station elevation
keyword: event
Modifier Parameter Type Explanation
start event identifier string Event constraint start tag.
The parameter is an arbitrary string used to identify the event
end none - Travel Time record end tag
info event info string arbitrary string giving additional event info.
lon 1. minimum value
2. maximum value
(3. mean value)
numeric Longitude constraint: event location is constrained to this longitude interval by external evidence
lat 1. minimum value
2. maximum value
(3. mean value)
numeric Latitude constraint: event location is constrained to this latitude interval by external evidence
depth 1. minimum value
2. maximum value
(3. mean value)
numeric focal depth constraint: event location is constrained to this focal depth interval by external evidence (depth is zero for meteorites!)
ot 1. minimum value
2. maximum value
(3. mean value)
numeric Origin time constraint: event origin time is constrained to this time interval by external evidence
keyword: arrival
Modifier Parameter Type Explanation
start record ID string Raw data record start tag.
The parameter is an arbitrar string used to identify the data record.
end none - Raw data record end tag
station station identifier string an arbitrary string, interpreted as station identifier. Does not necessarily correspond to a station identified by a station keyword in the same file.
event event ID string an arbitrary string, interpreted as event identifier. Does not necessarily correspond to a station identified by a event keyword in the same file.
phase phase name string a seismic phase name
at 1. minimum value
2. maximum value
(3. mean value)
numeric Phase Arrival Time
baz 1. minimum value
2. maximum value
(3. mean value)
numeric Back Azimuth inferred from Phase polarization
emerg 1. minimum value
2. maximum value
(3. mean value)
numeric Emergence angle inferred from Phase polarization
slo 1. minimum value
2. maximum value
(3. mean value)
numeric Slowness inferred from Phase polarization, surface velocity and/or other data

eof.