Sedimentary, dear Johnson: Is NASA looking at the wrong rocks for clues to Martian life?

In 2020, NASA and European-Russian missions will look for evidence of past life on Mars. But while volcanic, igneous rock predominates on the Red Planet, virtually the entire Earth fossil record comes from sedimentary rocks.Addressing the problem in Frontiers in Earth Science, Swedish scientists have begun compiling evidence of fossilized microbes in underexplored igneous rock environments on Earth, to help guide where to search for a Martian fossil record – and what to look for.
Source: EurekaAlert, https://www.eurekalert.org