Geologists say an undisturbed chamber of molten rock in Hawaii is offering new insight into the way continental rock is formed.

The magma, discovered in 2005 when a geothermal power company drilled a mile and a half deep on one of the islands, is the first contact scientists have had with the molten rock from anywhere other than a volcano, The Washington Post reported Thursday.

"This is Jurassic Park. This is first contact. Here we see this (continental) stuff being produced in its natural habitat," Bruce D. Marsh, a geologist at Johns Hopkins University, said at a meeting of the American Geophysical Union in San Francisco.

The chamber is the length of a football field and about 50 feet thick.

Continental rock is higher in silica than basalt rock. It is formed from magma as silica-poor compounds crystallize out, leaving silica-rich material that solidifies as it cools, the report said.