Total BS but you'd never believe it Doc.
NG did a docco on this called "The Truth Behind Crop Circles"
Lots of interviews and a group of 'fakers' attempted to make a complex geometrically exact replica of a shape designed by a mathematician - they did it perfectly in one night.
The overwhelming evidence suggested Hoax.
They even interviewed so called believers who re-enforced the hoax.
However like Jesus some find solace in the belief of circles and it helps them get through their day. So it aint all bad.
Try the nascar lines instead.
The Nazca Lines are a series of ancient geoglyphs located in the Nazca Desert of Peru. They have been designated a UNESCO World Heritage Site. The high, arid plateau stretches more than 80 kilometres (50 mi) between the towns of Nazca and Palpa on the Pampas de Jumana. Although some local geoglyphs resemble Paracas motifs, scholars believe the Nazca Lines were created by the Nazca culture between 200 BCE and 700 CE. The hundreds of individual figures range in complexity from simple lines to stylized hummingbirds, spiders, monkeys, fish, sharks or orcas, llamas, and lizards.
The lines are shallow designs made in the ground by removing the ubiquitous reddish pebbles and uncovering the whitish ground beneath. Hundreds are simple lines or geometric shapes; more than seventy are designs of animal, bird, fish or human figures. The largest figures are over 200 metres (660 ft) across. Scholars differ in interpreting the purpose of the designs, but they generally ascribe religious significance to them, as they were major works that required vision, planning and coordination of people to achieve.
The geometric ones could indicate the flow of water or be connected to rituals to summon water. The spiders, birds, and plants could be fertility symbols. Other possible explanations include: irrigation schemes or giant astronomical calendars.[1]
Due to the dry, windless and stable climate of the plateau and its isolation, for the most part the lines have been preserved. Extremely rare changes in weather may temporarily alter the general designs.