Near-bottom ROV multibeam bathymetry grid (ESRI ASCII format) from the Octopus Garden hydrothermal spring site

Near-bottom high-resolution bathymetry data were collected with a Reson 7125 multibeam sonar that is part of the MBARI Low Altitude Survey System (LASS) mounted for two dives in 2021 to the ROV Doc Ricketts, which was flown at 3 m altitude at speeds <= 1.0 m/s to produce 5 cm-resolution bathymetry grids and images from the multibeam. The grid file presented here is in ESRI ASCII format and the projection is UTM zone 10N. Position and attitude data were provided by a Kearfott SeaDevil Inertial Navigation System (INS) integrated with a 1200 kHz Teledyne RD Instruments Doppler velocity log (DVL) and a Paroscientific pressure sensor. The LASS sensor package was mounted in an articulating frame within an ROV tool sled that rotates from pointing the sensors vertically down to horizontally forward, allowing surveys of flat to vertical seafloor. The articulation is automated by closing a control loop around the difference between the forward and backward beams of the DVL. Funding was provided by a grant from the David and Lucile Packard Foundation to MBARI.

本数据集采用Reson 7125型多波束测深声呐（multibeam sonar）采集近海底高分辨率测深地形数据，该声呐为蒙特雷湾水族馆研究所（Monterey Bay Aquarium Research Institute, MBARI）低空勘测系统（Low Altitude Survey System, LASS）的组成部分。2021年，该系统搭载于遥控无人潜水器（Remotely Operated Vehicle, ROV）Doc Ricketts号完成两次下潜作业，潜水器以3米飞行高度、不超过1.0米每秒的航速航行，最终生成分辨率达5厘米的测深地形网格与多波束影像。本次发布的网格文件采用ESRI ASCII格式，投影坐标系为UTM 10N带。定位与姿态数据由Kearfott SeaDevil惯性导航系统（Inertial Navigation System, INS）提供，该系统集成了1200 kHz Teledyne RD Instruments多普勒测速仪（Doppler Velocity Log, DVL）与Paroscientific压力传感器。LASS传感器套件安装于ROV作业橇的铰接式框架中，该框架可驱动传感器从垂直向下旋转至水平向前，从而实现平坦至垂直海底的全覆盖勘测。该铰接动作通过围绕多普勒测速仪前后波束的差值构建闭环控制回路实现自动化。本项目的资助来自大卫与露西尔·帕卡德基金会向MBARI提供的专项拨款。