From an article in the February, 2001 edition of Petroleum News:
http://www.petroleumnews.com/pnarch/010228-49.html

"If there is life on Mars, it would probably be microorganisms in water
deep below the surface of the planet. Dr. Geoffrey Briggs, director,
Center for Mars Exploration at the NASA Ames Center, told “Meet Alaska”
that NASA is looking at ways to drill on Mars to look for water — and
the life it might contain.

Briggs said NASA has been working with Halliburton, Shell, Baker-Hughes
and the Los Alamos National Laboratory to identify drilling technologies
that might work on Mars."

Pat