Technology Helps Map Deepest Lake
Jul. 21, 2000
GRANTS PASS, Ore. (AP) _ Using the same deep-sea technology treasure hunters use to find Spanish galleons, scientists plan to map Crater Lake in hopes of unlocking the secrets of the volcano that formed it.
On Monday, a boat equipped with echo-sounding equipment will start sending its pings into the cobalt-blue waters of the nation's deepest and clearest lake, which formed from the caldera left after 12,000-foot Mount Mazama erupted 7,700 years ago.
Scientists living on Wizard Island will post online computer images of color topographic maps of each day's mapping.
``It's going to be way cool,'' said Mac Brock, chief of natural resources management at Crater Lake National Park.
The $200,000 effort is the first attempt to map the lake since 1959. It is a partnership between the National Park Service, which is paying most of the bill, the U.S. Geological Survey, which is overseeing the mapping, and the University of New Hampshire, which is leasing equipment from C&C Technologies Inc. of Lafayette, La.
The mapping will primarily focus on discovery of geothermal vents on the lake floor _ 1,932 feet below the surface at its deepest point _ which are a factor in the lake's chemistry and ecology. It will also try to get a better picture of the lake floor to help understand the volcanic eruption and formation of the lake.
``It is a natural outdoor laboratory for world-renowned research,'' Brock said. ``Knowing more about the lake bottom helps scientists worldwide know more about volcanic lakes worldwide.''
The initial soundings of Crater Lake in the late 1800s used piano wire and a lead weight to measure depths. In 1959, echo-sounding equipment measured the depth at 4,000 points around the lake. Besides the cinder cone that forms Wizard Island, the soundings show an underwater cone on the lake floor.
In 1988, scientists in a tiny submarine surveyed about 2 percent of the lake floor and discovered hydrothermal vents with bacterial mats and tiny mites living around them. The discoveries were used to fend off development of geothermal energy outside the park.
The latest mapping effort will generate data points in the tens of millions that are accurate to within 50 centimeters, said James Gardner, chief of Pacific seafloor mapping for USGS in Menlo Park, Calif.
On the Net:
Park service site: http://www.nps.gov/crla