Rick Hutchinson tracks the gurgling, bubbling and steaming that goes on throughout Yellowstone National Park, and he's got the latest equipment to get the job done.

But the seismometers, seismographs and infrared sensors aren't always the best stuff to monitor the park's more than 10,000 thermal features, the geologist says."There's real elaborate scientific equipment called a handful of pine needles," Hutchinson said, indicating his preference for sitting and watching geysers rather than reading printouts.

For the past 15 years Hutchinson's domain has been Yellowstone's geysers and hot springs, which ebb and flow as the park's underground boiler shifts with geologic activity.

"It's been very, very quiet so far this year and last," Hutchinson said of the earthquake activity while walking through the Lower Geyser Basin. "Usually Yellowstone, because of its volcanic plateau, has lots and lots of micro earthquake swarms. You know, ones that are too small to be felt.

"And usually you'll have, on the average, maybe a couple of dozen small felt ones. You know, just enough to rattle the windows, the dishes and things like that," he added. "That's what helps keeps the geysers going. Because if you don't have the earthquakes to flush out the deposition within the plumbing system of the vents, they'll eventually clog themselves up. The earthquakes can open new vents and allow the heat to come to the surface."

Yellowstone's thermal features include geysers, hot springs, mud pots and fumaroles. A geyser is a hot spring that becomes unstable and violently throws hot water and steam. Hot springs have no nozzle-like vents to cause violent eruptions. Mud pots contain more dirt than water. If there is not enough water, there are steam holes, or fumaroles.

Over Hutchinson's shoulder "Deep Blue" and "Deep Blue's Unnamed Satellite Vent" are proof that Yellowstone's plumbing system is doing just fine.

Deep Blue, a wide pool of superheated, azure-blue water was percolating away, taking time every 20 minutes or so to launch a steaming bubble of water into the air.

About 30 feet away, the satellite vent was sending a steady plume of steam and water almost 50 feet into the air. Since March the vent has been acting this way, and Hutchinson, nicknamed "geyser gazer," wants to know why.

Twenty-four hours a day the satellite vent gushes, releasing pent-up pressure that ripples to the surface throughout Yellowstone in search of a way out. The small geyser is just the latest peculiarity in Yellowstone's geyser inventory, which is headed by world-renowned Old Faithful.

The thousands of thermal features in the park are kept bubbling by lava flows running close to the Earth's surface. Many of the features are away from the boardwalks that take visitors through the West Thumb Geyser Basin, the Black Sand Geyser Basin, Biscuit Basin, the Norris Geyser Basin, Porcelain Basin and other basins.

But some, such as Deep Blue and its satellite vent, can be seen only at a distance from the boardwalks.