Compilation of tectonic map and Nd isotopic mapping for basalts in the seamount area of Western Pacific Ocean

The Tectonic Map of the Western Pacific Seamount Area (1∶5 000 000) is compiled based on the topographic and geological data of the COMRA cruises over past years and the latest geophysical and geochemical data. The tectonic map of the Western Pacific seamount area consists of one main map and three auxiliary maps. The main map or the tectonic map of mapping area includes 3 first order plates, 22 second order blocks and 12 third-order blocks, while the three auxiliary maps includes the geological structure map of the seamount area in Western Pacific Ocean, the bouguer gravity anomaly map of seamount area in the Western Pacific Ocean and the contour map of ε_Nd(t) value in seamount area of Western Pacific Ocean. The guiding idea and method adopted by the map compilation, the data source, the content of the map and the division basis of tectonic units are introduced and described in this paper. Based on the ε_Nd(t) data of the basalts in the Western Pacific region, nine Nd isotopic anomaly areas are delineated. The coupling relationship between the Nd distribution pattern and geological processes and its significance to tectonic division of the area are further discussed.