Volume reverberation is caused by junk (suspended particles, bubbles, etc) in the water causing uneven and unpredictable sound propagation and return. I've only ever used the phenomena as it relates to active sonar transmissions and returns, not ownship noise or passive sonar. I don't think it's much of a concern at the low frequencies involved in passive sonar.
What you're talking about sounds like bottom bounce and surface bounce, with OSN reflecting back directly onto OS sensors. Sounds like something unique to subs, and certainly new to me.
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