From Beyond Space and Time 2

A science fiction action adventure classic of the discovery of an ancient alien artifact.
Scientists, military, archeologists, and explorers uncover a fifteen-mile alien artifact from beyond space and time after it has been buried away for millions of years in a colossal crater on a desolate Pacific island, with a hideous monstrous alien entity hidden inside, waiting to be found and revived.
Weird creatures, hideous shapes, mind-bending monsters from the depths of time with organs and abilities never seen before are uncovered by paleontologists from rock, which has encrusted them for millions of years. They are trapped in modes of activities in a form like rock, but unbreakable, with a strange energy surge running through them (which they were instantaneously ensnared in on the alien artifact, in suspended animation, before its crash).
In its dark confines the explorers discover an entity/life form, dormant, in suspended animation, with more hideous characteristics than any life form they have ever encountered.