grains, which are seen in thin section [@Usui2009], are expected to carry overprints and are likely contaminating the high unblocking temperature direction. There is also a more exotic explanation. In the absence of a geodynamo, the high scatter could reflect a variable field produced by solar interaction with the Paleoarchean atmosphere. For example, the solar wind interaction with the thick atmosphere of Venus (a planet without an internally generated magnetic field) produces an external magnetic field which is more variable and more than an order of magnitude weaker than the surface field of Earth [@Zhang2007] (see also *section 7*). Hence, paleointensity becomes the key variable in evaluating these data further.\

Field Intensity Values at 3.4 to 3.45 Ga
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To obtain a field intensity at 3.45 Ga, @Tarduno2010 sampled the source of the Barberton Greenstone Belt dacite clasts; these were supplemented with a study of 3.4 Ga dacites from the Nondweni Greenstone Belt. In both belts, dacites contain quartz phenocrysts, 0.5 to 2 mm in size, which were the target of investigation. The ideal nature of the magnetic inclusions within the phenocrysts was confirmed by rock magnetic tests (e.g. magnetic hysteresis), and Thellier-Coe paleointensity data were collected using CO$_{2}$ laser 