Near-bottom magnetic anomaly and magnetization data (netCDF grids) from 9°50'N, East Pacific Rise, acquired in 2018, 2019 and 2021 during AUV Sentry dives

Near-bottom magnetic data was collected 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 1520 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 was gridded at 10 m × 10 m node resolution. The grid files are in GMT-compatible netCDF format, in un-projected geographic coordinates. Three grid files are presented here, as follows. File 2400mergeT.grd is the total magnetic field anomaly, upward continued to 2400 m below sea-level. File const20anni.grd is the total field crustal magnetization, calculated using constant layer 2A thickness of 500 m. File var20anni.grd is the total field crustal magnetization, calculated using variable layer 2A thickness, constrained from seismic reflection images (Harding et al., 1993; Marjanovic et al., 2018). Funding was provided by National Science Foundation awards OCE-1834797, OCE-1949485, OCE-1948936, and OCE-1949938.