09:46 AM PST on Friday, November 12, 2004

By GARY CHITTIM / KING 5 News.

A giant plug of pure lava is pushing higher inside the Mount St. Helens crater, raising the odds of a future explosive eruption.

Mount St. Helens has been rumbling with minor earthquakes since September. But in the last few days, the strength of the earthquakes has slowly begun to increase and scientists watching the action in the crater say it is suddenly very active.

USGS

"The gouge" in the Mount St. Helens crater began rising around Nov. 4, 2004.

When a photographer took an aerial tour of the Mount St. Helens crater Monday, he spotted something new, a massive uplift of pure lava.

It's a football field high, several football fields wide and growing into a near-solid lava mixture, 1,300 degrees Fahrenheit and easily the tallest, newest and most prominent feature of the crater.

Scientists have begun calling the giant area of uplift "the gouge".

"This is an amazing structure to rise up out of the crater floor," said UW seismologist Bill Steele.

Steele said pictures taken just a few days ago showed nothing abnormal in the crater. Then, all of a sudden, "starting around Nov. 4, this structure began emerging and has just shot up to over a hundred meters high."

"If it continues going up, it will reach a point where it becomes unstable and could topple over clearing the way for lava with more gas."

That could greatly increase the chances of an explosive eruption when highly pressurized magma suddenly moves closer to the surface.

Combine this with a slow steady climb in earthquake strength, and Mount St. Helens is once again building energy.

"There's no sign of this slacking off and it's very exciting and it's an amazing opportunity to watch a mountain being born right in front of our eyes," Steele said.

That is one reason why the warning level remains at alert level two, meaning eruptions could occur at any time.