ANATOMY OF DIVING WAVES

摘要

When velocity increases linearly with depth, rays are arcs of circles and reflections can come from the upper or lower surface (turning rays) of a dipping plane. In this paper, I examine the behavior of both types of reflections as a function of dip and azimuth. Reflections from the upper surface of a plane behave much like those for a constant velocity medium, the principal difference being movement downdip of a reflection point when the profile is in the strike direction, Reflections from the lower surface of a plane have no constant velocity analog. In addition to downdip movement of a reflection point for a strike line, the turning ray reflections have negative time stepout for a dip line and zero stepout for a profile near 45 degrees from dip. [References: 11]