NEWS-"Old Faithful's Plumbing Changes"
Date:	98-06-22 16:14:29 EDT
From:	hblonde1@tampabay.rr.com (New Millennium)

Old Faithful's Plumbing Changes 

June 22, 1998; 2:10 p.m. EDT

YELLOWSTONE NATIONAL PARK, Wyo. (AP) -- A mild earthquake hit
Yellowstone National Park last January, and Old Faithful and other
geysers haven't been the same since. 

Within a few hours, Cascade Geyser, virtually dormant since the late
1800s, began erupting. Vault Geyser, inactive since 1988, began spouting
so much water that it cut channels in the sediment surrounding it. 

About eight days later, Old Faithful's crowd-pleasing shows became a
little harder to predict. 

Before the earthquake, Old Faithful was erupting once every 74 minutes
on average. Since then, it has averaged more than 80 minutes between
eruptions, the longest interval since record-keeping began in the 1920s. 

Once during the winter, rangers watched the geyser wait 115 minutes
between eruptions. 

Experts are not certain whether the earthquake disturbed nature's
plumbing or whether changes in the geysers and their subterranean
waterworks caused the quake. 

The magnitude 2.2 quake struck on Jan. 9 about a mile from Old Faithful. 

Old Faithful has never operated like clockwork. Instead, it erupts for
two minutes then waits about an hour to do it again, or it erupts for
three to five minutes and then waits about 90 minutes. 

"It's nearly as predictable as it was before -- it's just that we've had
to change the prediction model," said Lynn Stephens, a statistician at
Eastern Washington University.