摘要 |
A METHOD IS DISCLOSED FOR AMPLITUDE PRESERVING KIRCHHOFF TIME MIGRATION. THE METHOD INCLUDES CALCULATING (12) ESTIMATES OF THE GEOMETRICAL SPREADING TERMS USING A CONSTANT VELOCITY APPROXIMATION. TAKEOFF AND EMERGENCE ANGLES ARE ACCURATELY CALCULATED (14) BASED ON A MODEL OF VELOCITY WHICH VARIES WITH RESPECT TO TRAVEL TIME. AN IMAGE CAN BE CALCULATED AT LEAST ONE TRAVEL TIME USING THE ESTIMATED WEIGHTS AND CALCULATED TAKEOFF AND EMERGENCE ANGLES.
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