RV Tangaroa Voyage TAN2021_V01 EM302 Multibeam Echosounder Data

This record describes deeper multibeam data collected on RV Tangaroa voyage TAN2021_V01 (NIWA TAN2113), which was carried out on a contract to the CSIRO MNF from 9th November to 4th December 2021. The voyage had two objectives, which were to recover 27 Ocean Bottom Seismometers which had been deployed around Macquarie Island on IN2020_v06, and complete multibeam and sub bottom profiler mapping along the crest of the Macquarie Ridge and collect new multibeam data during transits.

The Kongsberg Maritime EM302 was used to obtain swath bathymetry, backscatter, and water column data in deeper water (down to 7000 m), using Kongsberg Seafloor Information System (SIS) version 4.3.2 acquisition system. The EM302 is a 1 TX by 2 RX system, with 288 beams (or 576 beams in dual swath mode), yielding 432 soundings (or 864 soundings in Dual Swath mode ). Water column data, which show the received amplitude of the entire water column for each beam, were recorded simultaneoulsy with the multibeam echosounder data.

Data are stored in *.all raw format for bathymetry and backscatter and *.wcd format for watercolumn backscatter at CSIRO. There are 201 files totalling 25.2 GB of raw data in this dataset. There are 200 files totalling 43.8 GB of water colomn data.

Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.all format are corrected for motion and position.

Raw data (*.all files) were processed using QPS Qimera v2.4.2 for bathymetry and QPS Geocoder Toolbox (FMGT) v7.10.0 for acoustic seafloor backscatter.

*.gpd files were generated by Qimera for each *.all file after editing. The quality of the bathymetry data was examined, and surfaces of varying resolution generated for each survey area. The data were cleaned in both 2D and 3D manually. Where appropriate a medium spline filter was used. Gridded bathymetric surfaces were projected in WGS84 / UTM zone 57S (EPSG:32757) coordinate reference system at varying resolutions. Bathymetry datasets were collated, and maps produced in ArcGIS Pro v2.8.3.

Water column data files (.wcd) consisting of 165 files, 31.1 GB, were not processed onboard.

Additional information regarding this dataset is contained in the "NIWA Voyage Report 2022007WN.pdf". The report is available from Geophysical Survey and Mapping (GSM) group at CSIRO upon request.

本记录描述了塔ngaroa号科考船（RV Tangaroa）TAN2021_V01航次（NIWA TAN2113）采集的深水多波束数据。该航次于2021年11月9日至12月4日根据与CSIRO MNF的合同执行，包含两项目标：回收27台于IN2020_v06航次部署在麦夸里岛周边的海底地震仪（Ocean Bottom Seismometers）；完成麦夸里海岭脊部的多波束及浅地层剖面仪（sub bottom profiler）测图，并在航渡期间采集新的多波束数据。

康士伯海事（Kongsberg Maritime）EM302系统用于采集深水（最深达7000米）的条带测深数据（swath bathymetry）、反向散射数据（backscatter）及水柱数据（water column data），采集系统为康士伯海底信息系统（Kongsberg Seafloor Information System, SIS）4.3.2版本。EM302为1发射（TX）2接收（RX）系统，含288个波束（双条带模式下为576个），可产生432个测深点（双条带模式下为864个）。水柱数据记录了每个波束在整个水柱中的接收振幅，与多波束回声测深仪（multibeam echosounder）数据同步采集。

CSIRO存储的测深及反向散射原始数据格式为*.all，水柱反向散射数据格式为*.wcd。本数据集含201个原始数据文件，总大小25.2 GB；另有200个水柱数据文件，总大小43.8 GB。

数据采集期间已对数据应用声速剖面（Sound velocity profiles）。*.all格式中的测深数据已完成运动和位置校正。

原始数据（*.all文件）的测深处理采用QPS Qimera v2.4.2软件，海底声学反向散射处理采用QPS Geocoder Toolbox（FMGT）v7.10.0工具包。

编辑后，Qimera为每个*.all文件生成*.gpd文件。研究人员对测深数据质量进行了检查，并为各调查区域生成了不同分辨率的曲面。数据经手动二维及三维清理，必要时采用中等样条滤波器（medium spline filter）。网格化测深曲面投影至WGS84/UTM 57S（EPSG:32757）坐标参考系，分辨率各异。测深数据集经整理后，使用ArcGIS Pro v2.8.3制作成图。

含165个文件（总大小31.1 GB）的水柱数据文件（.wcd）未在船载系统中处理。

关于本数据集的更多信息见《NIWA Voyage Report 2022007WN.pdf》。该报告可向CSIRO地球物理调查与制图组（Geophysical Survey and Mapping, GSM）申请获取。