C INCLUDE 'initc.inc' C ------------------------------------------------------------------ INTEGER MSRFCA PARAMETER (MSRFCA=128) INTEGER ISB1I,ICB1I REAL YLI(6),YI(29),FSRFCA(MSRFCA) COMMON/INITC/ISB1I,ICB1I,YLI,YI,FSRFCA SAVE /INITC/ C ------------------------------------------------------------------ C ISB1I,ICB1I... Indices of a simple and a complex blocks in which C the initial point of the ray is situated (see C.R.T.6.1). C YLI... Array containing the values of the quantities YL(1)-YL(6) C (see C.R.T.5.5.4) describing the local properties of the C model at the initial point of the ray, see C.R.T.6.1. C They must not be changed outside the subroutine INIT2. C Description of YL C C YI... Array containing the following quantities describing the C properties of the rays and of the travel-time field, see C C.R.T.6.1: C YI(1)...Initial travel time. C YI(2)...Initial imaginary part of the complex travel time. C YI(3)-YI(5)... Coordinates of the initial point of the ray. C YI(6)-YI(8)... Covariant components of the initial slowness C vector. C YI(9)-YI(11)... Covariant components of the first basis vector of C the ray-centred coordinate system at the initial point of C the ray (perpendicular to the slowness vector C YI(6)-YI(8)). C YI(12),YI(16) QR11,QR12 C YI(13),YI(17) QR21,QR22 C YI(14),YI(18) PR11,PR12 C YI(15),YI(19)... PR21,PR22 C Elements of the ray geometrical spreading matrix QR, and C of the matrix PR (see C.R.T.,eq.(5.13)) at the initial C point of the ray. C YI(20),YI(21)... Take-off parameters of the ray. C C The above quantities are defined in subroutine INIT2 of file C 'init.for'. C INIT2 C Following quantities Y(22)-Y(29) are defined in subroutine RPAR4 C of file 'rpar.for'. C RPAR4 C C In addition to the above quantities describing the properties C defined for a single ray, there are also quantities describing C the properties of the discrete system of computed rays in the C vicinity of the computed ray. These quantities are C YI(22)..Area of the element of the ray-parameter surface, C corresponding to the ray, see C.R.T.,eq.(6.1). C YI(23),YI(24),YI(25)... Components 11, 12, 22 of the symmetric C matrix inverse to the specific moment of the element of C the ray-parameter surface corresponding to the ray, see C C.R.T.,eq.(6.2). C C Additional quantities related to the shooting algorithm: C YI(26),YI(27)... Normalized take-off parameters of the ray, both C taking the values between 0 and 1. C YI(28),YI(29)... For a successful ray, values of the X1 and X2 C functions parametrizing the reference surface. C X1 and X2 functions C Otherwise zeros. C C The index of the last allocated numeric unit of array FSRFCA is C named MSRFCA. Dimension MSRFCA may be adjusted if necessary. C C Common block /INITC/ is included in external procedures INIT1 and C INIT2 of 'init.for', in OUTP of 'raycb.for', in 'rpar.for', C in 'writ.for', in 'scropc.for', and may be included in any other C subroutine. C C Date: 1997, September 5 C Coded by Ludek Klimes C C======================================================================= C