Portal:Earth sciences/DYK/7

... that a world map by Gerardus Mercator attributes the Earth's magnetic field to a magnetic mountain (pictured) above the Arctic Circle?
... that a team of archaeologists discovered a fossilized Han Solo in the rocks of China?
... that forest rings had gone unnoticed by geologists until aerial photography became a common surveying tool in the 1950s?
... that two researchers have argued that some cobbles should be called "very small boulders"?
... that swarms of dykes have intruded into Uruguay?
... that precarious rock formations were evaluated to estimate the peak ground acceleration of the 1952 Kern County earthquake?