The Mariana Trench, located in the western Pacific Ocean approximately 200 kilometers (124 mi) east of the Mariana Islands, is the deepest natural point in the world.

Subduction

The trench is thought to be a subduction zone where the ocean floor of the Pacific is gobbled up by the continental plate to the west. So, it must have come as a surprise to researchers that this zone draws in water at an enormous rate. Because the quantity of water in a subduction zone should not go up, but down.

Subduction should push water out to the sides as the ocean floor is gobbled up.

Alternatively, subduction trenches must grow deeper at a rate that exceeds the volume lost by the shrinking ocean floor.

But the Mriana Trench is not growing deeper at the required rate. Yet water is rushing in towards it.

This leaves us with only two explanations.

Either, subduction is not in fact happening. Or there are drains at the bottom of the trench, sucking water into the Earth.

Absurd proposition

Unwilling to give up on the idea of subduction, and unable to find holes for water to drain into, geologists have come to the conclusion that water is somehow mixed with the rocks that subduct in under the continental plate to the west.

This would make the subducted rocks of very low density. But nowhere in physics do we see low density materials sink in under denser materials.

Yet, in geology, this is supposedly happening at an extraordinary rate.

The more logical explanation

A more logical explanation would be that the Mariana Trench is not in fact a subduction zone, but an expansion rift.

Because an expanding ocean floor at the trench, even if expanding at a slow pace, would require huge amounts of water to fill the the volume created.

Water would come rushing in to fill the expanding trench.

Conclusion

What geologists have discovered is not another fantastic mechanism of subduction, but further proof that Earth is expanding.

South pole view of the expanding Earth