Following the derivation of () and (), and applying simple trigonometry and geometry to Figure A-1, I obtain parametric equations for migrating an impulse recorded at time tD, data-midpoint mD, and data surface-offset hD as follows:
(17) |
where the total path length is:
(18) |
From that system of equations, () shows that the total path length is
(19) |
I can rewrite system A-17 as:
(20) |
where and follow the same definition as in equation A-3. The total path length, L, in terms of the angles and is:
(21) |