You can see these types of enclosures almost always along the margins of sand dune systems not only in Saudi Arabia, but in Iraq, and probably most of the other desert countries in the region. Just follow the dune margins. The seem to avg. 20-30 M in diameter, but are much less consistent, dramatic and simpler than the ones shown in the article - 31*04'52.59"N 38*48'57.70E and 31*05'04.69"N 38*48'25.69"E and many other areas (elevations around 2500 ft.
Given their consistent proximity to dune systems you might consider them as man made sand dams - though a sustainable population density in the area necessary to support these numerous structures seems implausible sustainability wise - unless they predate the desertification of the area - but then why are they seemingly only on the sand dune margins?
Looking at the vast numbers of these structures, their general lack of any consistent and purposeful form (man usually very quickly sorts out the best from that follows the the desirable function and then copies it repeatedly), they seem to be natural devices - geological or biological associated somehow with sand dunes more than man made structures.
I also did a small sample GE elevation survey of a number of these structures and it appears that each structure is a few feet lower than the surrounding area. This might imply they are some kind of water/rain catch basin related to the dunes and are being colonized by plants, but not be over grown in the middles where the evaporative alkali content would prevent plant growth.
Given their free-form nature, their lack of communicative resemblance to any cultural elements, they don't bear even the most remote similarity with the Nazca Lines. I would vote for natural processes more than man made.
Newly released photographs have provided the public with a rare glimpse into a mysterious site that archeologists consider Saudi Arabia’s version of the famous Nazca lines.
These impressive man-made designs, known as geoglyphs, were first discovered in 1927 but have since been shrouded in secrecy because many nations in the middle east prohibit researchers from excavating or even taking aerial photography. Fortunately, archaeologists now have their own not-so-secret tool to get around this problem called Google Earth.
David Kennedy, an archaeologist, used satellite-assisted software to capture detailed views of the giant stone structures, which date back at least 2000 years. The most common ones are circular with various spoke-like patterns that appear to resemble wheels and tend to be concentrated on lava fields. Their dimensions range from 82 feet to 230 feet across.
These latest findings are yet another example of how the combination of satellite technology and ultra high-resolution cameras have revolutionized the field of archaeology. Back in May, a team of archaeologists commissioned NASA satellites to survey Egypt and discovered more than 1,000 tombs and 3,000 ancient settlements. [READ: How NASA satellites unearthed Egypt’s lost pyramids]
And previously, Kennedy had used the program to probe nearly 2000 potential archaeological sites in the region, many of which were “pendants” or ancient stone tombs shaped like teardrops. All his research was done from his office chair using Google Earth’s satellite images.
Still, investigating relics from afar has its limitations. So far, none of the wheels appears to have been excavated, which makes dating them — and uncovering their purpose — a perpetually difficult task. For instance, some archaeologists have speculated that the ruins were likely once houses or cemeteries. Kennedy, however, disagrees.
Meanwhile, Amelia Sparavigna, a physics professor at Politecnico di Torino in Italy, has proposed what feels like a more obvious explanation.
“If we consider, more generally, the stone circles as worship places of ancestors, or places for rituals connected with astronomical events or with seasons, they could have the same function of [the] geoglyphs of South America, the Nazca Lines for instance. The design is different, but the function could be the same,” she told LiveScience.
While the original purpose of these remnants continue to baffle the masses, one thing we do know is that a “search” company, fittingly, has brought us ever closer to solving some of history’s greatest enigmas.
(via CBS News/LiveScience)
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