Release Date: March 15, 2000
HOUSTON -- Was there ever life on Mars? That question may one day be answered in part by research now being conducted by a University at Buffalo geologist who studies volcanoes on earth.
In a presentation here on March 17 at the 31st Annual Lunar and Planetary Science Conference, Tracy Gregg, Ph.D., assistant professor of geology in the UB College of Arts and Sciences, will discuss how her studies of volcanoes in specific locations on Earth may be able to help researchers learn about Martian volcanoes, and in turn, reveal the answers to mysteries surrounding the Martian climate of the past.
In particular, researchers will be looking for evidence of the past presence on Mars of water, the solitary ingredient that is most vital for proving the existence of past life on the planet.
"The underlying drive for this research is certainly to one day find out enough about what the Martian environment was like in the past in order to discern if it could have, in fact, sustained life," said Gregg.
According to the UB geologist, that issue is controversial: Some scientists believe that the clues available now support evidence of Mars having been able to sustain life of some sort in the past, while others say that the available data refute that.
For her part, Gregg believes that much more work needs to be done.
"Our research is one way of attacking the question of what Mars was like in the past," said Gregg, who did the work with colleague Michael F. Sheridan, Ph.D., UB professor of geology.
In her presentation, "Volcanoes as Meteorologists: Using Volcanic Morphology to Constrain Paleoenvironments on Earth and Mars," Gregg will report on what she and Sheridan have learned from studying the lava flow that filled Iceland's Skaelinger valley in 1783, the 1801 Kualelea Flow from Mauna Loa in Hawaii and explosion craters of the Pinacate volcanic field in Mexico.
On earth, Gregg explained, features of volcanoes whose last-known eruptions occurred hundreds, even thousands of years ago, have been used to pinpoint the locations of bodies of water, such as glaciers, rivers and lakes, which were displaced or destroyed by dramatic changes in climate, such as the advance and retreat of ice ages. These studies, which usually involve extensive fieldwork, laboratory analysis of samples and analysis of satellite data, also can tell researchers about the direction and distinguishing characteristics of these lava flows.
For example, at Iceland's Askja Caldera volcano, which has been active during the past 5,000 years, there is a small crater lake that was created by a 1834 lava flow. That lava flow, which still is visible, dramatically changes character from rough and spiny to smooth, several meters above the lake's present shoreline.
"That change tells us that the lake had much more water in it when the lava flowed into it," said Gregg, a piece of evidence that may point to a warmer climate.
She noted that this is exactly the kind of data that could be observed on Mars using a lander or rover equipped with cameras that can "see" these kinds of changes in lava flows and recognize key features of volcanic craters.
That kind of information helps scientists reconstruct past environments, a process that Gregg and Sheridan hope can be easily translated to Mars.
"We are using volcanic features to tell us what the environment was like when these volcanoes erupted," she said.
Similarly, the UB researchers say that high-resolution images of Martian volcanoes made by the Mars Observer Camera, which has been returning useful data from the Mars Global Surveyor Mission since 1998, together with the ability of landers and rovers to identify certain geologic features, will begin to address these issues for the red planet. They also will be using data collected by the Mars Orbiter Laser Altimeter to review the topography of Martian features to compare with similar ones on earth.