Hikurangi Trough

Oceanic trench off the east coast of New Zealand

The Hikurangi Trough,, is a sea floor feature of the Pacific Ocean off the north-east South Island and the east coast of the North Island of New Zealand. It has been forming for about 25 million years and is turbidite-filled particularly in its south. This characteristic can be used to distinguish it from the sediment–poor and deeper Kermadec Trench which is its continuation to the north. Sediment currently passing through the trough represents about 0.5% of the total sediment input to the world oceans. The trough has deep sea chemosynthetic ecosystems that are unique.

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