The geochemical characteristics of the surface sediments in the New Britain Trench of the Western Pacific Ocean and their implications for provenance

Most of the world trenches belongs to the hadal zone, the deepest part of the earth. The sources of sediments in the trenches are always different due to the difference in geographic location, topography, climate and others. In order to further understand the composition and sources of sediments in hadal trenches, the New British Trench, which is close to land, is chosen as the research object of this paper. By analyzing the geochemical characteristics of the bottom sediments of the trench, we studied the sources of sediments in different depths and regions of the trench. It is found that the bottom sediments of the New Britain Trench shaped like a reversed V are mainly derived from the surrounding volcanogenic materials, no matter they are located in the bathyal zone, abyssal zone, or even hadal zone. However, the materials in the western part of the reversed V shaped trench are rather different from those in its east. The western part of the New British Trench is mainly affected by volcanogenic materials from the Rabaul Volcano in the east of the New Britain Island, the northern part volcanoes of the New Britain Island, and the Solomon Islands, and the proportion of volcanogenic materials is the highest in the northeast stations from the northern part volcanoes of the New Britain Island. Compared to the western part, the eastern part of the New British Trench is more strongly affected by the TLTF volcanic chain (volcanoes Tabar-Lihir-Tanga-Feni). It is believed that the different sources of the New British Trench are related to the complex ocean currents between the western part and the eastern part of the trench. Furthermore, the bottom (the deepest) of the western part of the trench is dominated by river sediments but less influenced by volcanogenic materials.