Nieuwerkerk - Emperor of China (NEC) Seamounts (Banda Sea): A multibeam seafloor imagery analysis

Abstract

A new multibeam dataset of Nieuwerkerk and Emperor of China (NEC) seamounts was acquired during the Jalacitra 2-2022 ”Banda” Expedition in the Banda Sea region. This study discusses a morphometric analysis of the seamounts based on a high-resolution bathymetry digital elevation model (DEM) and describes the morphometric features, namely: slope, profile curvature, and aspect. Morphological results indicate that the Nieuwerkerk seamount has an area of 2,416 km2 with a maximum peak elevation of approximately 3,460 m above the seabed and 357 m below the water surface. In the southwest of the Nieuwerkerk seamount, two new seamounts were discovered, which are still unnamed and seem morphologically connected to the Nieuwerkerk seamount. Each of the seamounts covers an area of 148 km2 and 220 km2, respectively, with a maximum peak elevation of approximately 2,338 m and 2,053 m above the seabed. Additionally, both seamounts have an elevation of 1,878 m and 2,017 m below the sea surface. Meanwhile, the Emperor of China seamount is located southwest of the three formerly mentioned seamounts, with the maximum peak seats at 2,165 m below the sea surface. Seamount C is located in the west of the surveyed area and it covers an area of 95.6 km2 with an elevation of 1,834 m above the seabed. The results of regression analysis indicate that all of the features could be used for the morphological classification.

Geometry-based multi-beam survey line layout problem

“…The complexity of seabed topography often has a substantial impact on measurement accuracy and data integrity. To tackle these challenges, this study aims to establish a coordinate system tailored for a specific ocean area and seabed topographic conditions while leveraging geometric relations like triangle similarity and sine theorem [1] . A mathematical model is formulated to determine water depth and coverage width accurately while calculating the overlap ratio of survey ship positions [2] .…”

Research on Multibeam Bathymetric System Based on Geometrical Relation Mo Model

“…In the multibeam bathymetry system, the lead is hammered in the plane of the survey line and forms a slanting straight line with an angle of α with the horizontal plane, where α is defined as the slope. Considering the characteristics of the multibeam transducer, the opening angle is 120°, the slope is 1.5°, and the depth of seawater at the centre point is 70 m [11]. By establishing a mathematical model of the coverage width of the multibeam bathymetry and the overlap rate between adjacent strips, we are able to calculate the index value of each position in Table 1 more accurately, which can provide a reliable reference for the actual bathymetry.…”