US operator Apache brought a well back online this week shortly after it was shut in due to a truck fire at a site in the company's Alpine High asset.

A spokeswoman confirmed that the cab of an 18-wheeler caught fire on Thursday afternoon at Apache's Alta location, north of Interstate 10 in Reeves County. 

"There were no injuries reported, and the well at the location was shut in as a precaution," the spokeswoman said. "Apache activated its crisis response plan, and the fire was extinguished without incident."

The fire was blamed on "a mechanical issue with the truck", which was owned by an unnamed third-party services company.

The well was producing at the time of the incident but there were no activities ongoing at the site, Apache said.

"The well was back on line within a few hours, so no significant interruptions," the spokeswoman said, adding that no Apache property, personnel or assets were impacted by the fire.

Alpine High, which has been touted as one of the largest onshore oil discoveries of recent years, holds an estimated 3 billion barrels of oil and 75 trillion cubic feet of gas.

The properties are perspective for the Woodford and Barnett formations.

Apache has faced opposition from environmentalists over its drilling programme at Alpine High, which is near the scenic and sensitive Balmorhea State Park in West Texas. It has promised to develop the resource responsibly.