The Guijarral Hills are a range of low hills in the inner California Coast Ranges, in Fresno County

Fresno County, California

Fresno County is a county located in the Central Valley of the U.S. state of California, south of Stockton and north of Bakersfield. As of the 2010 census, it is the tenth most populous county in California with a population of 930,450, and the sixth largest in size with an area of . The county...

, California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

, about seven miles east of the town of Coalinga

Coalinga, California

Coalinga is a city in Fresno County, California. The population was 13,380 at the 2010 census, up from 11,668 at the 2000 census. It is the site of both Pleasant Valley State Prison and Coalinga State Hospital. Coalinga is located southwest of Fresno, at an elevation of 673 feet .-Early...

.

They are the surface expression of an anticlinal

Anticline

In structural geology, an anticline is a fold that is convex up and has its oldest beds at its core. The term is not to be confused with antiform, which is a purely descriptive term for any fold that is convex up. Therefore if age relationships In structural geology, an anticline is a fold that is...

 structure which continues to the south as the Kettleman Hills

Kettleman Hills

The Kettleman Hills is a low mountain range of the interior California Coast Ranges, in western Kings County, California. It is a northwest-southeast trending line of hills about 30 miles long which parallels the San Andreas Fault to the west....

, and to the north as Anticline Ridge, a portion of the huge Coalinga Oil Field

Coalinga Oil Field

The Coalinga Oil Field is a large oil field in western Fresno County, California, in the United States. It surrounds the town of Coalinga, about half-way between Los Angeles and San Francisco, to the west of Interstate 5, at the foot of the Diablo Range...

. The Guijarral Hills overlie the smaller and mostly exhausted Guijarral Hills Oil Field

Guijarral Hills Oil Field

The Guijarral Hills Oil Field is a formerly-productive oil and gas field near Coalinga on the western side of the Central Valley in central California in the United States...

. Jayne Avenue, which connects Interstate 5 to Coalinga, is the major east-west road through the hills.