Radiocarbon dates were analyzed to assess Vertisols age around the world. They show an increase of radiocarbon age from mainly modern–3000 BP in 0–100 cm layer up to 10,000 BP at a depth 100–200 cm. Older dates reflect the age of parent material. The inversion of 14C dates seems to be a frequent phenomenon in Vertisols. A series of new dates of Vertisols from gilgai microhigh, microslope and microlow in the North Caucasus was done in order to understand the nature of this inversion. 14C age in the gilgai soil complex ranges from 70 ± 45 BP in the microlow to 5610 ± 180 BP in the microhigh. A trend of similar depths being younger in the microslope and microlow was found. We explain this by intensive humus rejuvenation in the microlows due to water downward flow. The older date in the microhigh represents the old humus horizon sheared laterally close to the surface and preserved by impermeable water regime. We explain inversions of 14C age-depth curves by the sampling procedures. In a narrow pit, genetically different parts of former gilgai could easily be as a genetically uniform soil profile. Because of this strong microvariability, Vertisols require sampling in a trench accounting for gilgai elements, even when gilgai are not obvious.

The natural remanent magnetizations of Late Cambrian siltstones of the Wilberns Formation have been analyzed with alternating field, thermal, and Chemical demagnetization techniques. From mainly thermal demagnetization analyses a mean direction of magnetization has been calculated: declination D of 101.5 ø, inclination I of + 13.5 ø, k = 171, and ag• = 4.6 ø for seven sites (55 samples), yielding a virtual pole position at 6.4øN, 158.8øE, dp= 2.4 ø, and dm= 4.7 ø. This polar error (dp, din) represents the oval of 95% confidence about the pole position. Comparisons with previously published Late Cambrian data reveal good agreement between the thermally isolated directions of magnetization. The difference in the published results obtained through alternating field demagnetization can be explained by a late Paleozoic remagnetization or by a previously unexpected Cambrian shift or loop of the apparent polar wander path.

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