An intricate crop circle recently cut into a field two hours south of San Francisco baffled onlookers and spawned crackpot theories that aliens were responsible, but sources tell me it was created by Nvidia to publicize a big CES announcement. [Update: Nvidia confirms.] The design looks like Nvidia’s Tegra 4 chip, and though we can’t confirm this, it may be designed to drum up interest in the Tegra 5 chip Nvidia is expected to launch at CES.

Nvidia has a major CES press conference planned for tonight at 8pm PST in Las Vegas where it may fess up to creating the crop circle and is likely announce details of its new products.

[Update 6:30pm PST: Nvidia has confirmed it created the crop circle by adding this teaser image to its website.]

The Tegra is a “system on a chip” for mobile devices that combines a CPU, GPU, and memory controller. The new Tegra 5 Nvidia is expected to show off at CES is codenamed “Logan”, and will likely be faster and more energy-efficient than the Tegra 4 “Wayne” predecessor Nvidia showed at CES last year. Alternatively, the crop circle could related to the new Maxwell GPU Nvidia may unveil.

The crop circle appeared in the farming town of Chualar, California on the morning of Monday, December 30th. It was pressed into a field owned by a farmer named Scott Anthony who was out of town. On Tuesday, he ordered a crew to plough the crop circle, erasing it to the dismay of small crowds who had flocked to see it. You can see more footage of the crop circle and watch local news anchors’ hilariously misguided attempts to decode what it is in the embed below.

As tech companies battle it out for press at overcrowded conferences like CES and SXSW, publicity stunts are getting more and more ridiculous. Last year’s CES saw the typical, demeaning booth babes and free swag, but also paintball shooting galleries while SXSW parties featured celebrity performances from Justin Timberlake and Prince.

You could call these stunts signs of an indulgent tech bubble, but as gadgets and apps gain more and more mainstream appeal, there’s big money to be made in owning a moment with some theatrics. If Nvidia can sell more chips, it could easily make up for whatever the crop circle cost.

[Image: 111th Aerial Photography & Video via KDVR, KSBW, UFOSOnEarth]