Residual mantle Bouguer anomaly (RMBA) grid, 42-50 Ma NE Pacific between Molokai and Murray FZ

Residual mantle Bouguer anomaly grid calculated for the Ohana project located 25-30.5°N, 145.5-137.5°W in the NE Pacific. This ~500x600 km area was the site of an Ocean Bottom Seismometer array deployed Nov 2021-Feb 2023 by a team led by Gabi Laske. Donna Blackman led the bathymetric and gravity analyses. Gravity data processing started with the satellite-based Free Air Anomaly grid (grav_32.1.nc, Sandwell et al., 2014). The contributions of seafloor topography (from the corresponding bathymetry grid called Ohana_bathymetry_200m_v5n.grd), and of a constant thickness (6 km) crust were removed assuming 1700, 250, and 350 kg/m3 density contrasts at the seafloor, upper/lower crust (1.5 km depth), and basal interfaces, respectively. The best-fit exponential age trend of the predicted mantle Bouguer anomaly was removed as an estimate of the contribution of plate cooling for this 40-52 Ma area. The resultant RMBA data was gridded at 200 m. The RMBA data file is in GMT-compatible netCDF grid format.