Unusual Martian region leaves clues to planet's past

November 02, 2016

Researcher Don Hood from LSU and colleagues from collaborating universities studied an unusual region on Mars -- an area with high elevation called Thaumasia Planum. They analyzed the geography and mineralogy of this area they termed Greater Thaumasia, which is about the size of North America. They also studied the chemistry of this area based on Gamma Ray Spectrometer data collected by the Mars Odyssey Orbiter, which was launched in 2001. What they found was the mountain ridge that outlines Greater Thaumasia was most likely created by a chain of volcanoes. The results were published recently in the Journal of Geophysical Research-Planets.

"The chemical changes we see moving northwestward through the region is consistent with the mantle evolving on Mars. Our research supports that this whole area was built as a volcanic construct," said Don Hood, LSU Department of Geology and Geophysics doctoral candidate and lead author of the paper.

The chemical composition changes throughout the region. Silica and H20 increase and potassium decreases from southeast to northwest.

"The chemical composition shifting is the key progression that tells us that this environment was most likely shaped by a series of volcanic events that continually erupted from a changing mantle composition," Hood said.

Hood and colleagues from Stony Brook University, University of Tokyo and Lehigh University ruled out another hypothesis that the abundance of H20 and potassium was caused by water interacting in rock.

"We looked for evidence of aqueous alteration through other geochemical means and didn't find it," he said.

The geography of the region has many shield volcanoes that are similar to the ones found in Hawaii. However from geochemical analyses, the researchers found that the sulfur that is present was most likely deposited as a volcanic ash. Volcanic ash from various areas could be evidence of explosive volcanism on Mars, which would be an important clue for piecing together the history of Mars. It is significant because explosive eruptions emit a lot of gas that can stay in the atmosphere and can cause global cooling and warming events.

"Whether there was explosive volcanism on Mars and how much of it there was is an important question in terms of finding out what the past climate was like," Hood said.
-end-


Louisiana State University

Related Mars Articles from Brightsurf:

Water on ancient Mars
A meteorite that originated on Mars billions of years ago reveals details of ancient impact events on the red planet.

Surprise on Mars
NASA's InSight mission provides data from the surface of Mars.

Going nuclear on the moon and Mars
It might sound like science fiction, but scientists are preparing to build colonies on the moon and, eventually, Mars.

Mars: Where mud flows like lava
An international research team including recreated martian conditions in a low-pressure chamber to observe the flow of mud.

What's Mars made of?
Earth-based experiments on iron-sulfur alloys thought to comprise the core of Mars reveal details about the planet's seismic properties for the first time.

The seismicity of Mars
Fifteen months after the successful landing of the NASA InSight mission on Mars, first scientific analyses of ETH Zurich researchers and their partners reveal that the planet is seismically active.

Journey to the center of Mars
While InSight's seismometer has been patiently waiting for the next big marsquake to illuminate its interior and define its crust-mantle-core structure, two scientists, have built a new compositional model for Mars.

Getting mac and cheese to Mars
Washington State University scientists have developed a way to triple the shelf life of ready-to-eat macaroni and cheese, a development that could have benefits for everything from space travel to military use.

Life on Mars?
Researchers from Hungary have discovered embedded organic material in a Martian meteorite found in the late 1970s.

New evidence of deep groundwater on Mars
Researchers at the USC Arid Climate and Water Research Center (AWARE) have published a study that suggests deep groundwater could still be active on Mars and could originate surface streams in some near-equatorial areas on Mars.

Read More: Mars News and Mars Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.