The continental margin - a transitional suture-block zone of the Australian segment of the Pacific Ocean
In the Australian segment, the continental margin (transitional zone) has a complex structure where the island-arc systems (IAS) play an important role. They are located between the blocks of the lithosphere with either the continental or sub-continental crust, and the thick mature crust of the oceanic or sub-oceanic origin. Such blocks are the Island of New Guinea, the Admiralty and New Ireland Plateau, the Fiji basins plate, a part of the Solomon Sea basin, the archipelago of Tonga, New Zealand, etc. The IAS structures are the blocks of the oceanic origin. The island arcs follow the contours of the margins of the abovementioned blocks. The seismofocal surfaces are multidirectional inclined and some are vertical. The IAS is “squeezed” upward from the bottom of the lithosperic plate toward the day surface. Therefore, the IAS can be included in the suture-block type.