Field Observations and Lab Tests of Acid Brines: Implications for Past Deposition, Diagenesis, Erosion, and Life on Mars


Geochemical and mineralogical data obtained from lithified strata of Mars indicate that acid saline waters once existed on and just below its surface [1-5]. This confirms the interpretations of acid waters on Mars by Burns [6,7] based upon spectral signatures suggestive of jarosite and schwertmannite, as well as the theoretical work of Clark [8]. Acid saline environments on Earth are good analogs for martian lithified strata, especially those at Meridiani Planum [9,10]. In addition, acid brines may have been responsible for the formation of channels and some small craters on Mars [11,12]. We propose that acid brines should be considered possible agents of chemical sedimentation, diagenesis, and sediment transportation and erosion on Mars. Terrestrial acid saline lake systems are an uncommon, but natural, type of extreme environment. Here we summarize the characteristics of modern acid saline systems in Chile, Western Australia, and Victoria, Australia, and how they compare to martian strata. We also present both physical sedimentology and waterrock interaction experiments involving acid brines. Knowledge of the geology, geochemistry, and microbiology of terrestrial acid saline systems may lead to recommendations for future investigations of Mars and better understanding of its geologic evolution and search for possible past life.

Meeting Name

Seventh International Conference on Mars (2007: Jul. 9-13, Pasadena, CA)


Geosciences and Geological and Petroleum Engineering

Second Department

Biological Sciences

Keywords and Phrases

Australasia; Australia; Chile; Lake Tyrrell; Mars; Salar Gorbea; Salar Ignorado; South America; Victoria Australia; Western Australia; Yilgarn; Acidic Composition; Astrobiology; Brines; Chemically Precipitated Rocks; Deposition; Diagenesis; Eolian Features; Ephemeral Lakes; Erosion; Evaporation; Evaporites; Experimental Studies; Field Studies; Geochemistry; Inorganic Acids; Laboratory Studies; Lakes; PH; Paleoenvironment; Sedimentary Rocks; Sulfuric Acid; Surface Features; Terrestrial Comparison; Water-Rock Interaction

Document Type

Article - Conference proceedings

Document Version


File Type





© 2007 Lunar and Planetary Institute, All rights reserved.

Publication Date

01 Jul 2007