the exact tilting amount is uncertain. Nevertheless, the value of 6 x 10$^{22}$ A m$^{2}$ is probably an underestimate of the true field strength. Study of the Stillwater Complex yielded a high paleointensity of 92 $\mu$T [@Selkin2000]. After correction of anisotropy, this value was reduced to 46 $\mu$T, and after application of a cooling rate correction (based on SD assumptions) the value was further lowered to 32 $\mu$T, resulting in a final VDM of 4 x 10$^{22}$ A m$^{2}$. For the reasons discussed above, the cooling rate correction is an overestimate if PSD grains are present, suggesting that the Stillwater VDM reported by @Selkin2000 also underestimates the true field strength.

Thus, conservatively, the hypothesis that field strength was similar (i.e. within 50%) to that of the modern field cannot be rejected for the interval from the Proterozoic boundary to the mid-Archean at 3.2 Ga. Below, we discuss in more detail the constraints for field strength for the Paleoarchean.\

The magnetopause 3.45 billion years ago
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Arguably the least metamorphosed Paleoarchean rocks are found in the Barberton Greenstone belt of the Kaapvaal Craton, South Africa. Here, the peak temperatures can be as low as $<$350 $^{o}$C [e.g. @Tice2004]. Similar rocks are 