West - Help me figure out these dirt roads & circles? (seen flying over western US)

I've been wondering about this for several years, and it finally occurred to me to ask on flyertalk, because surely someone here knows.

Around the Western US, particularly in CO/UT/NV (I think) I've often seen little dirt roads that dead-end in small dirt circles. The spacing between the circles is approximately 1/2 mile between them.

For an example of what I'm talking about go to Google Maps, search on Mohrland, UT, then choose satellite view and look a bit to the east of the town. There's a ton of these roads & circles there.

There are also some a few miles to the NW of nearby Orangeville, UT.

They don't seem like campsites, farms, fire roads, or anything else I can think of. But what are they?

Note: my apologies if this isn't the correct forum to use.

If you go to Google maps for Mohrland, UT and then search for 'Mohrland Road and Marks Road' and look west/northwest from that intersection (less than a mile) to the nearest cleared plot of land (just off of Mohrland Rd), you'll clearly see the shadow of an oil pump (the low angle of the sun helps a lot).

Awesome, and thanks! (nice compelling explanation you gave...)

The second I saw the username "nerd", I was optimistic that my question had been answered. :)

So these are all oil wells?

Seems they are.

http://maps.google.com/?ll=39.486986,-110.94213&spn=0.012089,0.042615&t=h&z=15&vpsrc=6&layer=c&cbll=39.486988,-110.942147&panoid=O1asw8gz4GVjntTVo-h5bA&cbp=11,45,,0,0

yes, these are nodding donkeys for oil production

if you want to see an extreme example, check out west texas and parts of new mexico where there is a heavy oil (i.e. dense/viscous) oil production

this one is kern county california
http://g.co/maps/epgvp

For more discussion, please follow in the Travel->West forum. Ocn Vw 1K, Moderator, TravelBuzz.

Very interesting. Dirt roads and circles lead to nodding donkeys. I wasn't expecting that.