Crater Lake NP Research Continues to Excite, Amaze

Park Science, Vol. 9, No. 5
Fall 1989, pp. 5

National Park Service

Dept. of the Interior
Remarkable … spectacular … bizarre

These are among the words being used by research scientists about what they are finding during deep dives to the bottom of Crater Lake in this their third and final year of the three year hydrothermal research program there.

In addition to water samples whose chemical analysis indicate that a connection with a deep mantle source still exists on the lake floor, one of the project’s two principal investigators has discovered a scattering of murky aqua blue pools on the lake bottom.

Dr. Jack Dymond, who found the first such pool on August 14 during the submersible Deep Rover’s fourth 1969 dive, called them “bizarre, remarkable – I’ve never seen anything like it before.”

The first pool found rises slightly off the bottom with a yellow rim, kidney shaped, and approximately 3 to 4 feet wide by 6 feet long. The temperature of the aqua blue fluid in the pool is 1 degree Celsius warmer than the surrounding lake water. Dymond believes it may be a solution with high levels of dissolved salts.

Dymond’s co-principal, Dr. Robert Collier, on August 6 relocated the unusual bacterial mats found last summer and probed them, finding temperatures inside the mats to be 10.1 C., approximately 6.7 C. warmer than the surrounding lake waters.

Mark Buktenica, a Crater take NP aquatic biologist, has gathered rock samples along the lake floor as part of research sponsored by USGS. Buktenica took the one-person Deep Rover to a depth of 1,500 feel near Llao Rock and worked up the sleep caldera wall, collecting 10 rock samples.

USGS geologist Charles Bacon, a longtime researcher at the lake, was excited by the rocks. which Mount Mazama and the explosion that created the lake.

Jim Milestone, Crater Lake NP biologist, described further research this summer as having added significantly to what was learned about the bacterial mats discovered in 1986. The mats were thought last year to be only a few inches thick, but this year’s work shows the mats are actually about 2 1/2 feet thick.

“It’s pretty spectacular,” Milestone said, “to see these thick, flocculent mats.” (See Park Science, Spring 1969, pp. 3-4.)

Findings from the 1989 summer research will be reported in the Winter 1990 issue, which will be distributed early in January.

The following bulletin arrived at precisely press time for Park Science:“Scientists have found the warmest water ever detected in Crater Lake.“Oceanographer Jack Dymond measured a water temperature of 64 degrees F in a bacteria mat near the lake bottom this week (August 25) according to Jim Milestone, biologist for Crater Lake NP. The temperature is 25 degrees higher than the surrounding lake water, which is about 38 degrees F. The new mark is nearly 15 degrees warmer than the warmest deepwater temperature recorded last summer. “The new temperature reading could eventually be significant because the USGS defines ‘hydrothermal water’ as water that has a temperature of at least 10 degrees C or 18 degrees F higher than the surrounding water.”