Input Files for OAST

The input files for OAST is structured in 12 blocks, as outlined in Tables3 and 4. In the following we describe the significance of the various blocks, with particular emphasis on differences between SAFARI-FIP and OAST.

 

Table 3: Layout of OAST input files: I. Computational parameters.

Input parameter	Description	Units	Limits
BLOCK I: TITLE
TITLE	Title of run	-	80 ch.
BLOCK II: OPTIONS
A B C	Output options	-	40 ch.
BLOCK III: FREQUENCIES
FR1,FR2,NF,COFF,[V]	FR1: First frequency	Hz	>0
	FR2: Last frequency	Hz	>0
	NF: Number of frequencies		>0
	COFF: Integration contour offset	dB/	COFF
	V: Source/receiver velocity (only for option d)
BLOCK IV: ENVIRONMENT
NL	Number of layers, incl. halfspaces	-	NL
D,CC,CS,AC,AS,RO,RG,CL	D: Depth of interface.	m	-
.	CC: Compressional speed	m/s	CC
.	CS: Shear speed	m/s	-
.	AC: Compressional attenuation	dB/	AC
.	AS: Shear attenuation	dB/	AS
	RO: Density	g/cm3	RO
	RG: RMS value of interface roughness	m	-
	CL: Correlation length of roughness	m	CL>0
BLOCK V: SOURCES
SD,NS,DS,AN,IA,FD,DA	SD: Source depth (mean for array)	m	-
	NS: Number of sources in array	-	NS>0
	DS: Vertical source spacing	m	DS>0
	AN: Grazing angle of beam	deg	-
	IA: Array type	-	IA
	FD: Focal depth of beam	m	FDSD
	DA: Dip angle. (Source type 4).	deg	-
BLOCK VI: RECEIVERS
RD1,RD2,NR,IR	RD1: Depth of first receiver	m	-
	RD2: Depth of last receiver	m	RD2>RD1
	NR: Number of receivers	-	NR>0
	IR: Plot output increment	-	IR
BLOCK VII: WAVENUMBER SAMPLING
CMIN,CMAX	CMIN: Minimum phase velocity	m/s	CMIN>0
	CMAX: Maximum phase velocity	m/s	-
NW,IC1,IC2	NW: Number of wavenumber samples	-	NW =2M, -1 (auto)
	IC1: First sampling point	-	IC1
	IC2: Last sampling point	-	IC2NW

 

Table 4: Layout of OAST input files: II. Plot parameters.

Input parameter	Description	Units	Limits
BLOCK VIII: RANGE AXES
RMIN,RMAX,RLEN,RINC	RMIN: Minimum range on plots	km	-
	RMAX: Maximum range on plots	km	-
	RLEN: Length of x-axis for all plots	cm	RLEN>0
	RINC: Distance between tick marks	km	RINC>0
BLOCK IX: TRANSMISSION LOSS AXES (Only for Options A,D,T)
TMIN,TMAX,TLEN,TINC	TMIN: Minimum transmission loss	dB	-
	TMAX: Maximum transmission loss	dB	-
	TLEN: Length of vertical TL axes	cm	TLEN>0
	TINC: Distance between tick marks	dB	TINC>0
BLOCK X: DEPTH AXES (Only for Options C,D)
DUP,DLO,DLN,DIN	DUP: Min. depth for plots	m	-
	DLO: Max. depth for plots	m	-
	DLN: Length of depth axes	cm	DCLN>0
	DIN: Distance between tick marks	m	DCIN>0
BLOCK XI: CONTOUR LEVELS (Only for Option C,f)
ZMIN,ZMAX,ZINC	ZMIN: Minimum contour level	dB	-
(	ZMAX: Maximum contour level	dB	-
	ZINC: Contour level increment	dB	ZINC>0
BLOCK XII: SVP AXES (Only for Option Z)
VLEF,VRIG,VLEN,VINC	VLEF: Wave speed at left border	m/s	-
DVUP,DVLO,DVLN,DVIN	VRIG: Wave speed at right border	m/s	-
	VLEN: Length of wave speed axis	cm	VLEN>0
	VINC: Wave speed tick mark distance	m/s	VINC>0
	DVUP: Depth at upper border	m	-
	DVLO: Depth at lower border	m	-
	DVLN: Length of depth axis	cm	DVLN>0
	DVIN: Depth axis tick mark distance	m	DVIN>0