SC2020_V01 EM2040C multibeam water column bubble experiments

This record describes multibeam echo sounder data collected during field experiments on RV South Cape survey SC2020_V01. CSIRO’s Oceans & Atmosphere Shallow Survey Facility (SSF) undertook multibeam water column experiments over an artificial seep deployed near Kingston Beach, southern Tasmania. The goal of the experiments was to characterize the utility of high frequency multibeam water column data for the detection of gas seeps in very shallow water (<20 m). These experiments were aligned to inform the ANLEC R&D Carbon Capture and Storage Marine Monitoring and Verification (MM&V) project (ANLEC R&D 7-0816-0305) on the application of multibeam water column data for the detection of gas seeps in shallow water as a regular monitoring tool. The Geophysical Survey & Mapping team single-head EM2040C multibeam was mobilised on RV South Cape and bathymetry and water column data were collected over a custom-built bubble release system to simulate a shallow water gas seep at a test site near Kingston Beach, southern Tasmania. The EM2040 provides a 1.3° by 1.3° transmit and receive angular resolution respectively. Data were acquired at 300kHz frequency using single swath mode, short CW pulse, beam spacing set at equidistant and sector coverage set to 65° port and starboard (total coverage 130°). Data are stored in *.all raw format for bathymetry and backscatter and in *.wcd format for water column backscatter at the CSIRO. There are 397 *.all and 373 *.wcd files totaling 129 GB of raw multibeam data in this dataset. Sound velocity profiles were applied to the data during data acquisition. Bathymetry data contained in *.all format have been corrected for motion and position. Additional information regarding this dataset, including further information on processing streams, is contained in the GSM data acquisition and processing report (sc2020_v01_Bubble_experiments_CCS_Rev_1.pdf). Water column data were post-processed using custom MATLAB workflows. A variety of workflow methods were tested, with the processing results of each available in *.txt and *.jpg format. Additional data products may be available on request.

本数据集记录了“南角号”科考船（RV South Cape）SC2020_V01航次野外试验中采集的多波束回声测深仪（multibeam echo sounder）数据。澳大利亚联邦科学与工业研究组织（CSIRO）的海洋与大气浅层探测设施（SSF）在塔斯马尼亚南部金斯顿海滩附近的人工气体渗漏点开展了多波束水体柱体探测实验。本次实验的目标是评估高频多波束水体柱体数据在水深小于20米的极浅水域检测气体渗漏的应用效能。本实验旨在为ANLEC研发的碳捕获与封存海洋监测与验证（MM&V）项目（ANLEC R&D 7-0816-0305）提供技术支撑，验证多波束水体柱体数据作为常规监测工具在浅水区检测气体渗漏的应用可行性。地球物理探测与制图团队将单头EM2040C多波束系统部署于“南角号”科考船，在塔斯马尼亚南部金斯顿海滩附近的试验场地，通过定制的气泡释放系统模拟浅水区气体渗漏，同步采集了测深与水体柱体数据。EM2040C的发射与接收角分辨率分别为1.3°×1.3°。数据采集参数如下：工作频率300kHz，采用单条条带模式、短连续波（CW）脉冲，波束间距设为等距，扇区覆盖范围为左舷65°、右舷65°（总覆盖角度130°）。本数据集的测深与反向散射数据以*.all原始格式存储，水体柱体反向散射数据以*.wcd格式存储于CSIRO。本数据集共包含397个*.all文件与373个*.wcd文件，总原始多波束数据量达129GB。数据采集阶段已应用声速剖面进行校正。*.all格式存储的测深数据已完成运动校正与位置校正。有关本数据集的更多信息（包括处理流程的详细说明）收录于GSM数据采集与处理报告（sc2020_v01_Bubble_experiments_CCS_Rev_1.pdf）。水体柱体数据已通过定制MATLAB工作流完成后处理。团队测试了多种工作流方法，各方法的处理结果以*.txt与*.jpg格式留存。额外数据产品可根据申请提供。