Near-bottom AUV Sentry raw magnetic data (ASCII format) from 9°50'N, East Pacific Rise (2021, RR2102)

Near-bottom magnetic data was collected at the East Pacific Rise, from 9°50'N, during a total of 20 AUV Sentry dives conducted from R/V Atlantis and R/V Roger Revelle during 2018 Atlantis cruise AT42-06 (three dives); 2019 Atlantis cruise AT42-21 (ten dives); and, 2021 Revelle cruise RR2102 (seven dives). Track lines were spaced 170 m apart, with Sentry about 70 m above bottom, collecting magnetic data using three Applied Physics Systems Model 1540 triaxial fluxgate magnetometers mounted on AUV Sentry. Sentry navigation was obtained using a 300 kHz Teledyne Doppler velocity log (DVL) and a Sonardyne AvTrak2 ultra-short baseline (USBL) acoustic positioning system, combined with an iXblue Phins inertial navigation system (INS), and a Paroscientific 8B7000-I Digiquartz depth sensor. The magnetic data are in ASCII text format, with one file each for top, port, and starboard magnetometers. Each ASCII file contains 11 columns, as follows: lon (degrees), lat (degrees), time (unix time, seconds), depth (m), altitude (m), roll (degrees), pitch (degrees), heading (degrees), X, Y, Z components of magnetic field strength (in oersted, i.e. x10^5 nT). Note that the magnetic data are X,Y,Z in sensor coordinates. The Sentry dive number and magnetometer mount point location is given in the file name. The three ASCII files for each dive correspond to one combined MATLAB file in an associated data set. Funding was provided by National Science Foundation awards OCE-1834797, OCE-1949485, OCE-1948936, and OCE-1949938.本数据集采集于东太平洋海隆北纬9°50′区域，所使用的近底磁测数据由搭载于自主水下航行器（Autonomous Underwater Vehicle，简称AUV）Sentry的20次下潜任务获取，下潜任务分别由亚特兰蒂斯号研究船（R/V Atlantis）与罗杰·雷维尔号研究船（R/V Roger Revelle）执行：2018年亚特兰蒂斯号航次AT42-06完成3次下潜，2019年亚特兰蒂斯号航次AT42-21完成10次下潜，2021年雷维尔号航次RR2102完成7次下潜。本次任务的测线间距为170米，AUV Sentry距海底约70米，通过安装在其平台上的3台应用物理系统公司（Applied Physics Systems）Model 1540型三轴磁通门磁力计采集磁测数据。AUV Sentry的导航定位系统由300kHz泰莱达因（Teledyne）多普勒测速仪（Doppler Velocity Log，简称DVL）、索纳戴恩（Sonardyne）AvTrak2超短基线（Ultra-Short Baseline，简称USBL）声学定位系统、iXblue Phins惯性导航系统（Inertial Navigation System，简称INS）以及帕罗斯科学公司（Paroscientific）8B7000-I Digiquartz深度传感器组合搭建而成。磁测数据采用ASCII文本格式存储，分别对应顶置、左舷及右舷三台磁力计的数据文件。每个ASCII文件包含11列数据，依次为：经度（单位：度，lon）、纬度（单位：度，lat）、Unix时间（Unix time，单位：秒）、水深（单位：米）、航行高度（单位：米）、横滚角（单位：度）、俯仰角（单位：度）、航向角（单位：度）以及磁场强度的X、Y、Z三分量（单位：奥斯特（oersted），即1×10^5纳特斯拉（nT））。请注意，此处X、Y、Z分量为传感器坐标系下的磁场分量。文件名中包含AUV Sentry的下潜编号以及磁力计的安装位置信息。每次下潜对应的三个ASCII文件可合并为关联数据集中的一个MATLAB格式文件。本数据集由美国国家科学基金会（National Science Foundation）资助，项目编号分别为OCE-1834797、OCE-1949485、OCE-1948936及OCE-1949938。