Topographic expression of the Danger Islands Troughs and implications for the tectonic evolution of the Manihiki Plateau, western equatorial Pacific Ocean

• Main Authors: Nakanishi, M, Nakamura, Y, Coffin, MF, Hoernle, K, Werner, R
• Format: Article in Journal/Newspaper
• Language: English
• Published: Geological Society of America 2015
• Subjects: Earth Sciences; Geology; Marine Geoscience; Danger Islands; Pacific
• Online Access: https://doi.org/10.1130/2015.2511(11; http://ecite.utas.edu.au/106066

The Manihiki Plateau in the western equatorial Pacific Ocean is a Cretaceous Large Igneous Province. Several studies have proposed that the Manihiki Plateau was formed by the same mantle plume that formed the Ontong Java and Hikurangi plateaus ca. 125 Ma. Recent multibeam bathymetric surveys of the Manihiki Plateau reveal the morphology of the Danger Islands Troughs (DIT), Suvarov Trough, which are systems of deep troughs within the plateau. The troughs divide the Manihiki Plateau into three distinct provinces, the North Plateau, the Western Plateaus, and the High Plateau. The DIT between the High Plateau and Western Plateaus comprises four en echelon troughs. With one exception, all segments of the DIT are bordered by steep escarpments, to 1500 m high. The basins of the DIT are smooth. Elongated northeast-southweststriking scarps are common in the southernmost DIT and at the junction between the DIT and Suvarov Trough. The features revealed by the new bathymetric data indicate that a sinistral strike-slip tectonic environment formed the DIT during the break-up into the Manihiki and Hikurangi plateaus, whereas the Suvarov Trough developed after the formation of the DIT.