The evt-file contains all available phase picks and analysis parameters of th SHM program. It is a plain text file and is pretty good self-explaining. It has one information per line with the general format
<descriptive text>: <value>
The available parameters are:
Station code: name of the station where a phase pick was made. Taken from trace when phase pick is done. Possible values: text string of maximum length 10.
Onset time: time of phase pick. Taken from trace where phase pick is done. Possible values: absolute time in SH time format
Onset type: type of phase onset. Taken from phase dialog box. Possible values: keywords 'emergent', 'impulsive'.
Phase name: name of picked phase. Taken from phase dialog box. Possible values: text string of maximum length 20.
Sign: sign of first onset of specified phase. Taken from phase dialog box. Possible values: keywords 'positive', 'negative'.
Component: component where phase was picked. Taken from trace where phase pick is done. Possible values: single character.
Period (sec): dominant period of phase in s. Measured via amplitude/period menu entries (e.g. Ampl & Period auto Peak). Possible values: floating point number.
Amplitude (nm): estimated displacement amplitude of measured signal in nm. The determined signal amplitude is divided by the amplitude transfer function of the recording equipment at the signal period. Measured via amplitude/period menu entries. Possible values: floating point number.
Amplitude Time (sec): time (s) relative to phase pick where amplitude was measured. Determined via amplitude/period menu entries. Possible values: floating point number.
Vel. Amplitude (nm/sec): estimated velocity amplitude of measured signal in nm/s. The determined signal amplitude is divided by the amplitude transfer function of the recording equipment at the signal period. Measured via amplitude/period menu entries. Possible values: floating point number.
LP component: not used. Possible values: single character.
LP period (sec): not used. Possible values: floating point number.
LP amplitude: not used. Possible values: floating point number.
BB amplitude (nm/sec): broadband amplitude in nm/s measured on unfiltered broadband records. Measured via amplitude/period menu entries. Possible values: floating point number.
BB period (sec): signal period in s. Measured via amplitude/period menu entries on unfiltered broadband records. Possible values: floating point number.
Beam-Slowness (sec/deg): slowness of phase in s/deg (modulus of horizontal slowness vector) measured using array algorithms (Plane Wave, FK). Possible values: floating point number.
Beam-Azimuth (deg): azimuth of phase in deg (complementary to Beam-Slowness) measured using array algorithms. Possible values: floating point number.
Epi-Slowness (sec/deg): corrected slowness in s/deg (modulus of horizontal slowness vector) of phase computed via Calibration menu entry. Used on P phases for location purposes. Possible values: floating point number.
Epi-Azimuth (deg): corrected azimuth of phase in deg (complementary to Epi-Slowness). Possible values: floating point number.
Distance (deg): epicentral distance in deg. Computed in location programs. Possible values: floating point number.
Distance (km): epicentral distance in km. Computed in location programs. Possible values: floating point number.
Quality number: phase quality number between 1 (=bad) and 9 (=good). Taken from phase dialog box. Possible values: integer numbers 1 to 9.
Magnitude ms: magnitude ms computed via magnitude menu entries. Possible values: floating point number.
Magnitude mb: magnitude mb computed via magnitude menu entries. Possible values: floating point number.
Magnitude ml: magnitude ml computed via magnitude menu entries. Possible values: floating point number.
Magnitude mw: magnitude mw. Possible values floating point number.
Broadband Magnitude: broadband magnitude computed via magnitude menu entries. Possible value: floating point number.
User Magnitude: user defined magnitude value. Not used by SHM. Possible values: floating point number.
User Magn. Description: Description text to above user magnitude. Possible values: text string of maximum length 40.
Source Region: name of epicentral region. Usually computed in location programs. Possible values: text string of maximum length 80.
Comment: arbitrary text to comment an event. Possible values: text string of arbitrary length.
Latitude: epicentre latitude in deg. Computed in location programs. Possible values: floating point number.
Longitude: epicentre longitude in deg. Computed in location programs. Possible values: floating point number.
Location method: which algorithm used to get location. Set by location program. Possible values: keywords 'array beam (calibrated)', 'array beam (uncorrected)', 'array beam (resid. corr.)', 'hypoellipse', 'locsat', 'hypocenter', 'hypo71', 'hyposat', 'relative travel times', 'external'.
Location quality: describes quality of location. Taken from parameter box. Possible values: keywords 'too weak', 'incoherent', 'no bearing', 'region', 'reliable'.
Velocity model: velocity model used for location of epicentre. Possible values: text string of maximum length 40.
Location Input Params: additional input parameters for external location programs. Possible values: text string of maximum length 80.
Applied filter: filter applied to trace when phase pick was done. Possible values: text string of maximum length 80.
Depth (km): source depth in km. Computed in location programs or set by user. Possible values: floating point number.
Depth type: type of depth given. Possible values: keywords '(n) preset', '(g) estimated', '( ) free', '(?) poorly constrained', '(*) less well constrained', '(d) reliable'.
Origin time: origin time of event. Computed by location programs. Possible values: absolute in SH time format.
Event ID: unique event ID assigned automatically by SHM in menu entry Final Parameters. Possible values: integer number.
Weight: phase weight derived from phase quality number. Meanwhile obsolete. Possible values: integer numbers 1 to 4.
Onset Accuracy: not used. Possible values: keywords 'seconds', 'milliseconds'.
Reference Latitude: latitude in deg of reference point (used in array location method). Possible values: floating point number.
Reference Longitude: longitude in deg of reference point (used in array location method). Possible values: floating point number.
Reference Location Name: name of reference location (reference station name). Possible values: text string of maximum length 10.
Analyst: initials of analyst. Prompted at startup of SHM if requested. Possible values: text string of maximum length 10.
No. of Stations used: number of stations used in location. Set in location programs. Possible values: integer number.
Region Table: name of region table used. Possible values: keywords 'Flinn-Engdahl', 'GEO_REG', 'SEIS_REG'.
Region ID: ID number of source region. Computed in location programs. Possible values: integer number.
Event Type: type of event analysed. Taken from phase dialog box. Possible values: keywords 'teleseismic quake', 'nuclear explosion', 'regional quake', 'local quake', 'quarry blast', 'mining event'.
Source of Information: agency reporting the event, taken from menu entry Info Source. Possible values: text string of maximum length 10.
Ampl&Period Source: where the amplitude measurement was done. Possible values: keywords 'direct', 'beam trace', 'align trace'.
Onset Window Left: time resolution of onset pick. SHM allows the specification of onset time errors. This specifies the left inaccuracy time window in s relative to pick. Possible values: floating point number.
Onset Window Right: time resolution of onset pick. SHM allows the specification of onset time errors. This specifies the right inaccuracy time window in s relative to pick. Possible values: floating point number.
Error in Latitude (km): location error in km in latitude direction. Computed by the location program. Possible values floating point number.
Error in Longitude (km): location error in km in longitude direction. Computed by the location program. Possible values floating point number.
Error in Depth (km): depth error in km. Computed by the location program. Possible values: floating point number.
Error in Origin Time: origin time error ins. Computed by location program. Possible values: floating point number.
Error Ellipse Major: error ellipsis major axis in km. Computed by the location program. Possible values: floating point number.
Error Ellipse Minor: error ellipsis minor axis in km. Computed by the location program. Possible values: floating point number.
Error Ellipse Strike: strike angle of error ellipsis in deg. Computed by location program. Possible values: floating point number.
Max Azimuthal Gap (deg): maximum azimuthal gap in observing stations. Possible values: floating point number.
RMS of Residuals (sec): root mean square of time residuals quantifying the location fit. Possible values: floating point number.
Phase Flags: flags set on phase. Possible values: text string of maximum length 6.
Signal/Noise: signal to noise ratio, determined with S/N menu entries. Possible values: floating point number.
Residual Time: residual time of phase in s. Computed by location programs. Possible values: floating point number.
Residual Correction: empirical corrections to residual times (experimental). Possible values: floating point number.
Pick Type: type of phase pick. Possible values: keywords 'manual', 'automatic', 'theoretical'.
Corner Frequency: not used. Possible values: floating point number.
Low Frequency Level: not used. Possible values: floating point number.
Moment Tensor Elements: not used. Possible values: text string of maximum length 80.
Moment Tensor Descr.: Possible values: text string of maximum length 80.
Scalar Moment: not used. Possible values: floating point number.
Fault Plane Solution: not used. Possible values: text string of maximum length 80.
FPS Description: not used. Possible values: text string of maximum length 80.
This page last modified 11-Mar-2006