Summary of outputs of 48 numerical geodynamo simulations each run with differing input parameters but in a spherical shell with the geometry of the present day outer core. Outputs mostly pertain to the 5 QPM criteria set out by Sprain et al. (2019) and were calculated using the same approach. Sprain C.J., Biggin A.J., Davies C.J., Bono R.K., Meduri D.G., 2019. An assessment of long duration geodynamo simulations using new paleomagnetic modeling criteria (QPM), Earth planet. Sci. Lett., 526, 115758.

The dataset created includes natural remanent magnetisation (NRM) of archive-half core sections recovered at nine sites (i.e. Sites U1422, U1423, U1424, U1425, U1426, U1427, U1428, U1429, and U1430) during IODP Expedition 346. NRM of the archive-half core sections were measured at every 5-cm interval resolution before and after 20-mT alternating field (AF) demagnetisation treatment. The dataset created also includes NRM of discrete samples taken from working-half core sections (typically one discrete sample per core from the longest hole at each drilling site). NRM of discrete samples were measured before and after a complete stepwise AF demagnetisation routine (up to 60-mT peak AF field). All NRM data collected were used to construct magnetostratigraphy for all sites drilled during Expedition 346. All data have been published in IODP proceedings Volume 346 (http://publications.iodp.org/proceedings/346/346toc.htm).

All the raw experimental data obtained for the study reported in Hodgson, E., Grappone, J. M., Biggin, A. J., Hill, M. J., & Dekkers, M. J. (2018). Thermoremanent behavior in synthetic samples containing natural oxyexsolved titanomagnetite. Geochemistry, Geophysics, Geosystems, 19. https://doi.org/10.1029/2017GC007354

The vast majority of palaeomagnetic recordings held in rock and meteorites are contained in small inhomogeneously magnetised particles that have a single-vortex (SV) domain state. The reliability and fidelity of the magnetic recording in these particles can only be determined using a numerical micromagnetic approach. This data set provides the first comprehensive examination of domain state as a function of grain size, grain shape and temperature for both magnetite and iron. The results show that SV domain states are highly stable, and in some cases more stable than their ‘ideal’ uniformly magnetized counterparts. With the data sets in this archive it is possible to determine the magnetic recording and stability characteristics of assemblies of grains that can be matched to a wide variety of grain distributions found in terrestrial rocks and meteorites.

This dataset comprises palaeointensity measurements from the Bourinot volcanic units (~505 Ma) and the Itabaiana dyke swarm (~525 Ma), with associated palaeomagnetic and rock magnetic metadata. The dataset covers Cambrian igneous units from two geographically distinct regions: the Bourinot volcanic sequence of Cape Breton Island, Nova Scotia (Avalonia), dated to ~505 Ma, and the Itabaiana dyke swarm of northeastern Brazil (Gondwana), dated to ~525 Ma. Together, these units sample magmatic rocks emplaced on separate palaeocontinental blocks during the early–middle Cambrian, providing geographically and tectonically independent constraints on geomagnetic field behaviour during this interval. The Excel file contains specimen-level palaeomagnetic and palaeointensity measurement data from Cambrian igneous units. It includes stepwise laboratory measurement records for individual specimens, comprising directional data (declination and inclination), magnetic moment and vector components, and associated experimental metadata. Each row represents a single laboratory measurement step within demagnetisation or palaeointensity experiments (e.g. IZZI-type Thellier protocols). The columns document specimen identifiers, experiment and method codes, instrument information, analysts, treatment conditions (thermal, alternating-field, and microwave where applicable), applied laboratory fields, measurement sequence, quality flags, and timestamps. Supporting metadata include citations, laboratory standards, and descriptive fields required for reproducibility and data reuse. The dataset is formatted to be compatible with established palaeomagnetic data standards and supports reconstruction of full experimental workflows for palaeointensity analysis.

Data from the IODP Expedition will be archived by the International Ocean Discovery Program, including all data generated during the shipboard palaeomagnetic and magnetic anisotropy analyses and all of the logging data (FMS tool, GBM data), plus associated explanatory notes. Shore based palaeomagnetic and magnetic anisotropy data, FMS---based reorientation parameters, and downhole magnetizations inferred from modelling of the GBM borehole magnetometer data will be made available to the international community via appropriate IODP Data Reports (in addition to primary journal articles). Data Includes: Shipboard cryogenic magnetometer data Shipboard and shore based discrete sample remanence data Shipboard and shore based magnetic anisotropy data FMS---based reorientation parameters Magnetic parameters modelled using borehole magnetometer data