"Journey to the Center of the Earth" is cinematic sci-fi proof that the Earth's core is made of cheese. Who knew?

Mercifully, it's old-fashioned family-friendly B-movie cheese, served up in this Brendan Fraser/Jules Verne action epic for kids.

Seek out this "Journey" in a theater showing it in 3-D. You'll want the T. rex, with his snapping teeth, the bioluminescent birds, the gigantic Venus flytraps and that mouthwash Fraser spits down his sink all right in your face. Or lap. This is 3-D the way it used to be — playful, used for effect, but not really a technology that can lift a middling movie much beyond tolerable.

Fraser stars as Trevor Anderson, a teacher of "tectonics physics," a man who has studied the deep geology of the Earth and its relationship to the drift of continents. His brother did the same.

But Max, that brother, went missing 10 years ago. When Trevor baby-sits Max's 13-year-old son, Sean (Josh Hutcherson), they stumble across Max's annotated copy of Jules Verne's "Journey to the Center of the Earth." Max, it appears, was a "Vernian," somebody who took the 19th-century sci-fi writer's fiction as fact. And he disappeared looking for a way into the center of the Earth.

So the lads race to Iceland to follow Max's trail, take up with a doubting and sexy Icelandic mountain guide (Anita Briem) and work their way into the planet through a volcano, facing one crisis after another with one one-liner after another.

"Dibs on the mountain guide!"

The Verne novel has been adapted every 20 years or so, pretty much since the dawn of cinema. The fantastical notion of a primordial "world within the world" is irresistible as juvenile entertainment.

The director, former special effects specialist Eric Brevig (he worked on "Total Recall," among other films), doesn't skimp on the spectacle, though any movie set in caves and abandoned mine shafts — time for a mine-shaft-cart roller coaster ride! — is, by definition, an overdose of blacks, browns and, ahem, "earth tones."

Fraser, as he proved in the "Mummy" movies, has a lightness to his performances that keeps this from turning tedious. The short running time helps, too.

Is it fantastic as film fantasy? Not really. But then, if you've got anything in memory to compare it to, it's not for you. As a fun piece of kids' sci-fi, "Journey" has science and pseudo-science and cliffhanging action, all flung at you in those wacky 3-D glasses.

Let this be your guide. "If you're old enough to recall any earlier 'Journey to the Center of the Earth,' you're too old for this one." Unless, of course, you need more cheese in your diet.