Bluefin Voyage BF2019_V01 EM2040c Multibeam Echosounder Data

This record describes multibeam echosounder data collected on Bluefin voyage BF2019_V01, 'Hydrographic Survey of the Freycinet, Huon and Tasman Fracture Australian Marine Parks' which departed Hobart, Tasmania on the 8th March 2019 and returned to Beauty Point, Tasmania on the 22nd March 2019. CSIRO’s Geophysical Survey and Mapping, Shallow Survey Facility (SSF) was contracted by the Institute for Marine and Antarctic Studies (IMAS) of the University of Tasmania (UTAS) in collaboration with Parks Australia, to undertake a 2 week hydrographic survey of the Freycinet Australian Marine Park to complete surveying of the Park out to approximately 300 m. Depending on weather conditions further surveying of the Huon and Tasman Fracture sites could also be attempted. Two sites, Pedra and South West Cape survey areas, were undertaken for comparison data outside of Marine Park areas.Nick Dando from Geoscience Australia (GA) mobilised their Kongsberg EM2040c Mulitbeam Echosounder (MBES) system onboard the MV Bluefin in Hobart on Thursday and Friday 7-8 March with assistance from Stuart Edwards, Craig Davey and Bernadette Heaney, CSIRO. Divers from IMAS attached the transducer to the hull of the ship.The GA system also included a POSMV navigation system, a Valeport sound velocity profiler (and a spare profiler) Bridge display laptop and Bridge display screen.The Kongsberg EM2040c multibeam echosounder was used to acquire seafloor bathymetry and backscatter information and watercolumn backscatter at the Freycinet, Huon and Tasman Fracture Australian Marine Parks surrounding south and south eastern Tasmania. The EM2040c provides a 1.3° by 1.3° transmit and receive angular resolution respectively. The echosounder's nominal frequency was 300 kHz and was operated in dual swath mode. Data are stored in *.all raw format for bathymetry and backscatter and *.wcd format for watercolumn backscatter at CSIRO. Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.all format are corrected for motion and position. Tide corrections were not applied to the final processed dataset. Instead the data was mapped to the ellipsoid (GPS Height) and thereafter reduced to AHD (Australian Height Datum) using the AusGeoid09 model. Processed data has had outliers removed. Processed line data are available in *.gsf and ascii format, and processed bathymetry and backscatter grids in geotiff format. Additional information regarding this dataset, including further information on processing streams, is contained in the GSM data acquisition and processing reports. Additional data products may be available on request.

本记录描述了“蓝鳍”号（MV Bluefin）BF2019_V01航次采集的多波束回声测深仪（multibeam echosounder）数据。该航次名为“Freycinet、Huon及Tasman断裂带澳大利亚海洋公园水文测量”，于2019年3月8日从塔斯马尼亚州霍巴特出发，3月22日返回塔斯马尼亚州比尤特角。

澳大利亚联邦科学与工业研究组织（CSIRO）地球物理测量与制图浅海测量设施（SSF）受塔斯马尼亚大学（UTAS）海洋与南极研究所（IMAS）委托，联合澳大利亚公园管理局，对Freycinet澳大利亚海洋公园开展为期两周的水文测量，以完成该公园内水深约300米范围的测量工作。视天气条件而定，还可尝试对Huon和Tasman断裂带区域进行进一步测量。此外，还在Pedra和西南角两个非海洋公园区域开展了测量，以获取对比数据。

澳大利亚地质科学局（GA）的Nick Dando在CSIRO的Stuart Edwards、Craig Davey及Bernadette Heaney协助下，于2019年3月7-8日（周四至周五）在霍巴特将其Kongsberg EM2040c多波束回声测深仪（MBES）系统部署至MV Bluefin上。IMAS的潜水员将换能器安装于船体。

GA系统还包括POSMV导航系统、Valeport声速剖面仪（含备用剖面仪）、舰桥显示笔记本电脑及舰桥显示屏。

Kongsberg EM2040c多波束回声测深仪用于采集塔斯马尼亚南部及东南部周边Freycinet、Huon和Tasman断裂带澳大利亚海洋公园的海底地形、反向散射信息及水体反向散射数据。该设备的发射与接收角分辨率均为1.3°，标称频率为300 kHz，运行于双条带模式。

CSIRO将地形和反向散射数据以*.all原始格式存储，水体反向散射数据以*.wcd格式存储。数据采集过程中已应用声速剖面。*.all格式中的地形数据已进行运动和位置校正。

潮汐校正未应用于最终处理数据集。相反，数据先映射到椭球面（GPS高度），再通过AusGeoid09模型转换至澳大利亚高程基准（AHD）。处理后的数据已剔除异常值。

处理后的测线数据以*.gsf和ASCII格式提供，处理后的地形和反向散射网格以GeoTIFF格式提供。关于该数据集的更多信息（包括处理流程的详细说明）见GSM数据采集与处理报告。其他数据产品可按需索取。