Recently, Wisconsin geologists, both
amateurs and professionals, calling themselves crater hunters,
have been examining the evidence of craters of meteorite explosions
upon earth's surface which was prevalent over other areas in North
America back when Wisconsin and western Russia once shared the space
south of the equator. It has been estimated that the rate of falling
meteors were up to 100 times more than the rate today and with
falling space rocks the size of a football field, hitting the planet
every 10,000 years. The ancient bombardment occurred during the
Ordovician
Period.
Earth's geological history in terms of
continental drift stretches out over a thousand million years with
marked results in 500 million year intervals. Maps that depict these
ages and drifts are an estimation. Each 500 million year interval was
followed by about 100 million years of geological episodes called
rifting as continents broke apart due to erosion and other natural
phenomenon.