SCAR (Scientific Committee on Antarctic Research)

Addendum 1.0 to SCAR Report #9 (August 1992)
January 22, 2002

Data-collector costs and data submission for CD-ROM production

Addendum 1.0	Appendix A	Appendix I	Appendix II	Appendix III
Appendix B	Appendix C	Appendix D	Appendix E	Appendix F

Appendix E : Example of processing parameter

PROCESSED BY		GECO U.K.
DEMULTIPLEX FROM SEG-B
PROCESSING SAMPLE INTERVAL		4 ms
START OF DATA DELAY		-40 ms
SPHERICAL DIVERGENCE COMPENSATION
DESIGNATURE		SHOT BY SHOT USING SUMMED AUTOCORRELATIONS (EXCEPT FOR LINES AMG845-15 AND AMG845-16)
PREFILTER		8Hz - 70 Hz (ONLY LINE AMG845-15 AND AMG845-16)
DECONVOLUTION
	TYPE	MINIMUM PHASE LEAST SQUARES INVERSE
	OPERATOR LENGTH	300 ms
	PREDICTION LAG	24 ms (FOR LINE AMG845-16 TO AMG845-18) 36 ms (FOR LINE AMG845-19 TO AMG845-24)
NMO CORRECTIONS		VELOCITIES FOR NMO CORRECTIONS DERIVED FROM CONTOURED VELOCITY SPECTRA. VARIABLE VELOCITY GATHERS AND VARIABLE VELOCITY STACKS
PRE-STACK MUTE
COMMON DEPTH POINT STACKING
	FOLD	24
	OFFSET WEIGHTING	BY X / (X +XL) (FOR ALL LINES EXCEPT AMG845-16) PROPORTIONAL TO X (FOR LINE AMG845-16)
	3 TRACE RUNNING MIX	WEIGHTS 1 : 2 : 1
STATIC CORRECTIONS
	SHOT AND STREAMER STATIC	+12 ms
BANDPASS FILTER
	LC (Hz)	HC (Hz)	SLOPES (Db per octave, low/high)
	15	75	30/120
EQUALISATION
	WINDOW LENGTH	1000 ms
	PERCENTAGE OVERLAP	50