This dataset consists of wide-angle seismic, electric field and magnetometer time series data recorded using 14 Ocean-Bottom Instruments (OBIC UK), along a carefully chosen ~200 km line at the magma-poor Goban Spur rifted margin in the north-east Atlantic Ocean, southwest of UK, in 2023. The data were acquired during RRS James Cook cruise JC251. The 14 OBIC instruments were equipped with 3-component geophones and 2-component horizontal electrode dipoles with 12 m antennas, and 10 of them had additional 3-component fluxgate magnetometers. All measurements were recorded at 250 Hz sampling rate. Alongside the OBIC dataset, the Deep-towed Active Source Instrument (DASI) waveforms, altimeter and conductivity-temperature-depth (CTD) measurements are also included. A detailed description of the acquisition and instruments can be found in the cruise report at: http://www.bodc.ac.uk/resources/inventories/cruise_inventory/report/18305/. The aim was to quantify the evolution of serpentinisation and magmatism at a magma-poor rifted margin as seafloor spreading is initiated, including whether serpentinisation of exhumed mantle is focused in discrete fault zones, and whether magmatism increases abruptly or gradually. These data were acquired by scientists from the National Oceanography Centre Southampton, Scripps Institute of Oceanography (SIO), and University of Southampton as part of the NSFGEO-NERC funded project 'Quantifying evolution of magmatism and serpentinisation during the onset of seafloor spreading' (Grant ref: NE/T007419/1). The collinear 34 SIO Mk III OBEM seafloor magnetotelluric/electromagnetic sensor data can be obtained from http://www.marine-geo.org/tools/files/32309#datasets.