Review komatiites: from Earth's geological settings to planetary and astrobiological contexts

Research areas:
Year:
2007
Authors:
  • Delphine Nna Mvondo
  • Jesus Martinez-Frias
Journal:
EARTH MOON AND PLANETS
Volume:
100
Number:
3-4
Pages:
157-179
Month:
June
ISSN:
0167-9295
BibTex:
Abstract:
Komatiites are fascinating volcanic rocks. They are among the most
ancient lavas of the Earth following the 3.8 Ga pillow basalts at Isua
and they represent some of the oldest ultramafic magmatic rocks
preserved in the Earth's crust at 3.5 Ga. This fact, linked to their
particular features (high magnesium content, high melting temperatures,
low dynamic viscosities, etc.), has attracted the community of
geoscientists since their discovery in the early sixties, who have tried
to determine their origin and understand their meaning in the context of
terrestrial mantle evolution. In addition, it has been proposed that
komatiites are not restricted to our planet, but they could be found in
other extraterrestrial settings in our Solar System (particularly on
Mars and Io). It is important to note that komatiites may be extremely
significant in the study of the origins and evolution of Life on Earth.
They not only preserve essential geochemical clues of the interaction
between the pristine Earth rocks and atmosphere, but also may have been
potential suitable sites for biological processes to develop. Thus,
besides reviewing the main geodynamic, petrological and geochemical
characteristics of komatiites, this paper also aims to widen their
investigation beyond the classical geological prospect, calling
attention to them as attractive rocks for research in Planetology and
Astrobiology.