Niuafo'ou Plate
This plate is sandwiched between the Pacific Plate to the north , the very unstable Tonga Plate to the east and the Australian Plate to the west . 
<triplet> Pacific Plate <subj> Tonga Plate <obj> shares border with <subj> Australian Plate <obj> shares border with <triplet> Australian Plate <subj> Pacific Plate <obj> shares border with <subj> Tonga Plate <obj> shares border with