Which sea floor features is not commonly found at active continental margins?

The sea floor feature that is not commonly found at active continental margins is the mid-ocean ridge. Mid-ocean ridges are formed by the spreading of the ocean floor at divergent plate boundaries, which are typically found in the middle of ocean basins. Active continental margins, on the other hand, are formed by the collision of two tectonic plates, one of which is continental and the other is oceanic. The collision of these plates results in the formation of mountain ranges, volcanoes, and other features characteristic of active continental margins.