When I see something odd or noteworthy I take measurements and record it. Sometimes later I learn something and have an “aha!” moment about it. I’m starting to believe that the earths magnetism sometimes naturally creates geometric alignments in striations of rock. Just a hunch. University of Texas at Dallas has this to say on the subject:

Many rocks contain iron-bearing minerals that act as tiny magnets. As magma or lava cool, these minerals begin to form. At this point the molten rock has not completely solidified, so the magnetic minerals floating in the molten mass, become aligned to the magnetic field. When the rock finally solidifies, these minerals “lock in” the magnetic field as so many tiny compasses. Sedimentary rocks also have a magnetic record. As iron bearing sedimentary minerals are deposited from the water column, they also become aligned with the existing magnetic field. The magnetism remains locked in the rock unless the rock is subsequently heated above the Curie Point, the temperature at which all magnets lose their magnetism. When the heated rock again cools below the Curie Point, it will record the magnetic field at this later time, and the old magnetic field will be lost. It is important, therefore, to establish that a rock’s magnetism is primary and has not been re-set at a later time.

Photos from Joshua Tree National Park off Geology Tour Road.

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