Most genetic models for uranium deposits in sandstones in the U.
Changes in the earth's magnetic field from normal polarity to reversed polarity or vice versa.
Suppose B has concentrations P2, D2, and N2.
Interval of time when the earth's magnetic field is oriented so that magnetic north pole is approximately in the same positions as the geographic south pole strata singular:
Description: Atomic clocks, which are the most accurate in the world, rely on the same principle. Scientists discovered that rocks could be timepieces -- literally.