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Not possible. The uncertainty of bathymetry in areas only mapped using gravity is larger than the dimensions of a sub.

Even in very well mapped areas, think of the effort in the Indian ocean to find MH370, this would require the assumption that the sub is moving, which is not always the case, e.g. if the sub halts propulsion and drifts with a current.

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Well yes, it's the surface disturbance of the underwater wake that they are detecting. So the sub has to be moving under its own power.

But there is no need for high resolution and the wake of the sub stands out starkly even with a large field of view. So I'm not sure it can evade detection by halting propulsion and drifting. The point at which it halted would be known and it would be detected as soon as it restarted, unless it was carried by an unknown current far enough to be out of view of the satellite.

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