and are from low metamorphic grade geologic terrains. The magnetic properties of common Archean rock types vary on a grain (mineral) scale, so meeting these challenges is rarely possible using whole rock samples.\

Single Crystal Paleointensity
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One approach to address these challenges is a focus on the paleomagnetism of single crystals rather than bulk rocks, using the single silicate crystal paleointensity (SCP) approach. Silicate crystals are not of intrinsic magnetic interest, but they often host minute magnetic particles that are ideal magnetic recorders [@Cottrell1999; @Dunlop2005; @Feinberg2005; @Tarduno2006]. In Mesozoic lavas, feldspars bearing magnetic inclusions have been shown to alter less in the laboratory than the whole rocks from which they were separated [@Cottrell2000]. The SCP approach (using feldspar from lavas) has been used to study geomagnetic field intensity versus reversal frequency for the last 160 million years [an inverse relation is supported; @Tarduno2001; @Tarduno2002; @Tarduno2005], and during the Kiaman Superchron [@Cottrell2008]. The SCP method has also been applied to olivine from pallasite meteorites [@Tarduno2012]. The SCP approach has allowed examination of the field of the Late, Middle and Early (Paleo) Archean as discussed below.\

Prior Proterozoic-Archean Paleomagnetic Field Constraints\
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Most prior characterizations of the Archean field have been 