[meteorite-list] Secrets to Life on Mars, Predicting Volcano Eruption May be Locked in Tiny Bubbles

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Wed Jun 2 18:57:14 2004
Message-ID: <200406022257.PAA19219_at_zagami.jpl.nasa.gov>

http://www.innovations-report.com/html/reports/earth_sciences/report-29788.html

Secrets to Life on Mars, Predicting Volcano Eruption May be Locked in Tiny
Bubbles

Innovations Report
June 1, 2004

By summer 2005, researchers in the Fluids Research Laboratory at Virginia
Tech will be able to look for evidence of water on Mars by examining
submicroscopic bubbles in martian meteorites, determine whether fluids and
silicate melts trapped in volcanic rock can help predict future eruptions,
and locate buried mineral deposits using data from surface rocks. Robert
Bodnar, University Distinguished Professor in the Department of Geosciences
in the College of Science, has received equipment grants from the National
Science Foundation (NSF) that will make the lab one of the best equipped for
the study of fluid inclusions in the United States.

When minerals form on Mars or deep in a volcano on Earth, small droplets of
fluid, vapor, or silicate may be trapped. These tiny, ancient samples
contain the rock's chemical history and represent time capsules from the
moment they were sealed in a rocky envelope. Recovering that moment in time
has been a long-term challenge for geoscientists.

"Scientists can learn a lot about the composition of such inclusions by
observing their behavior during heating and cooling under the microscope,"
said Bodnar, "but to really learn what is going on, you have to do
quantitative chemical analysis." Non-destructive techniques using lasers to
approximate the compositions of inclusions have existed for many years. Now
there is an instrument that goes a step further - actually digging or
ablating into the inclusion and removing the fluid for direct chemical
analysis.

Bodnar learned in late May that he has received a $400,000 Major Research
Instrumentation grant from the NSF to purchase an "Excimer-laser Based Laser
Ablation System coupled to an inductively coupled plasma mass spectrometer
(LA-ICP-MS)." "It is the single most important analytical method for those
studying the geochemistry of Earth fluids," said Stephen E. Kesler,
professor of geological sciences at the University of Michigan.

Last year, Bodnar had received $450,000 from NSF and Virginia Tech to
upgrade the lab with two Raman microprobes, one of them specifically
designed for the analysis of petroleum inclusions. "It uses a UV laser and
will help us understand whether a given basin or rock might host oil
deposits based on analysis of fluid inclusions in surface rocks, which could
save millions of dollars in fruitless drilling, or at least help identify
the most promising sites," said Bodnar.

The latest acquisition, which will be in place by next summer, will be a
national resource. There are only three other LA-ICP-MS systems specifically
designed for analysis of fluid inclusions in the world - at the Swiss
federal technical university (ETH) in Zurich, where the system was
developed, at the University of Leeds, and at Australian National
University, Canberra. Bodnar's newly equipped lab will become the National
Laser Ablation ICP-MS Laboratory for Fluid Inclusion Analysis.

At a 2002 meeting in Denver, sponsored by the NSF and the Society of
Economic Geologists, the establishment of an LA-ICP-MS laboratory in the
United States was identified as a number one instrument priority, and it was
suggested that it be located in Bodnar's lab at Virginia Tech because of his
long history of fluid inclusion research. Bodnar was invited to apply for an
MRI and 37 leading scientists provided letters of support.

"There is no better location than Virginia Tech for such a laboratory in
North America," said Kesler. "Dr. Bodnar is a pioneer in work on both
natural and experimental fluid inclusions and has a reputation for
thoroughness that is important to the scientists that will use this
facility."

Bodnar's interest in fluid inclusions began when he was a master's student
at the University of Arizona 25 years ago and continued through his PhD
research at Penn State University to the present time. The Mars research is
one of Bodnar's recent interests, now shared by his students. Work to
predict volcanic activity at the Vesuvius volcano that destroyed Pompeii in
79 AD is a joint project with researchers at the University of Naples.
Bodnar's early work on fluid inclusions involved studies of extinct
volcanoes that host some of the world's largest copper and gold deposits.

Bodnar is searching martian meteorites for samples of fluid inclusion, which
are rare in these extraterrestrial samples. He and his graduate student,
Megan Elwood Madden, a native of Jacksonville, Ill., are creating
geochemical computer models to predict what fluids would have been on Mars
at the time the rocks now comprising the meteorites were formed. "Our
findings would help answer questions regarding the presence of water on
Mars, which is crucial for the development and survival of life," Bodnar
said.

Madden, a Ph.D. student with funding from the NSF VTAdvance program, is
examining fluid inclusions in other space material as well as in terrestrial
meteorite impact sites, including Meteor Crater in Arizona. Previous studies
of meteorites indicate that Earth is not so unique, as fluid inclusions
indicate that water has been present on other bodies in the solar system at
some time in their history (Zolensky, Bodnar, Gibson, Nyquist, Reese, Shih,
Wiesmann, Science, Aug. 27, 1999).

Bodnar is looking at melt inclusions from the magma chambers associated with
volcanoes. A melt inclusion is a droplet of silicate material, rather than a
fluid, that was trapped in a mineral. "Our research collaboration with the
University of Naples is looking at melt inclusions in the magma from
Vesuvius," Bodnar said.

Naples, with more than a million residents, sits on the flank of this active
but sleeping volcano.

Luca Fedele a Ph.D. graduate of Virginia Tech who is a now faculty member at
the University of Naples, and Claudia Cannetelli, a PhD student from Naples,
have come to Blacksburg for the summer to conduct research on melt
inclusions from the Vesuvius volcano. "The LA-ICP-MS system will enable us
to analyze the composition of the melt inclusions to determine the
composition of the Vesuvius magma at the time of eruption," Bodnar said.

The researchers have determined that the composition of magma changes. "If
the composition at a particular time can be related to when a volcano
erupts, then knowing the composition might be an aid in predicting
eruptions," Bodnar said.

"Predicting volcano activity is an active area of research," Bodnar said.
Many researchers are studying Mount Rainier in Washington, another dormant
volcano that is near 2.5 million people in the Seattle Tacoma metropolitan
area.

Bodnar is also studying the role that volcanoes play in forming valuable
mineral deposits. Volcanic magma can contain rich deposits of gold or copper
- or not. Bodnar's focus is porphyry copper deposits, which include the
famous Bingham Canyon, Utah, and Butte, Mont., deposits, although he has
studied gold deposits related to volcanoes as well (reported in The
Economist Oct. 21, 1995). "One to two kilometers below the top of a volcano,
as the magma chamber cools, minerals precipitate. Later, the volcano is
eroded to reveal these deposits. When I study these deposits, I am studying
the 'fossil' of a volcano," Bodnar said.

"There are thousands of fossil (or extinct) volcanoes worldwide, but only a
few have concentrations of metals that can be mined. Why? Fluid inclusions
offer the key to answering this question," Bodnar said.

As molten magma cools and crystallizes, water enters and is heated. What
happens at this "magmatic hydrothermal, or hot-water, transition determines
whether or not an ore deposit forms, he said. "We want to analyze melt
inclusions and fluid inclusions that formed at the same time to try to
understand what happens to the chemistry within the magma chamber as the
system evolves from the magmatic stage to the hot-water stage."

"The few LA-ICP-MS analyses of fluid inclusions that have been made provide
information on the amount of metal that is dissolved in natural, ore-forming
fluids, and analyses of melt and sulfide inclusions are providing important
insights on the geochemistry of incompatible elements during magmatic
crystallization," said Kesler. "Preliminary data are challenging well
established concepts and are likely to lead to completely new theories about
the processes that form mineral deposits and other geochemical anomalies in
the upper crust."

Meanwhile, mining companies could save hundreds of millions of dollars in
exploration costs if analysis of inclusions in surface rocks could indicate
whether or not to drill.

Researchers from around the world will be able to use the new National
Facility for Laser Ablation Analysis of Fluid Inclusions at Virginia Tech to
explore rocks hundreds of millions of years old for knowledge ranging from
how copper and gold deposits formed to the opportunities for life across the
solar system.
Received on Wed 02 Jun 2004 06:57:02 PM PDT