A Martian analog in Kansas: Comparing Martian strata with Permian acid saline lake deposits

Abstract

An important result of the Mars Exploration Rover's (MER) mission has been the images of sedimentary structures and diagenetic features in the Burns Formation at Meridiani Planum. Bedding, cross-bedding, ripple marks, mud cracks, displacive evaporite crystal molds, and hematite concretions are contained in these Martian strata. Together, these features are evidence of past saline groundwater and ephemeral shallow surface waters on Mars. Geochemical analyses of these Martian outcrops have established the presence of sulfates, iron oxides, and jarosite, which strongly suggests that these waters were also acidic. The same assemblage of sedimentary structures and diagenetic features is found in the salt-bearing terrestrial red sandstones and shales of the middle Permian (ca. 270 Ma) Nippewalla Group of Kansas, which were deposited in and around acid saline ephemeral lakes. These striking sedimentological and mineralogical similarities make these Permian red beds and evaporites the best-known terrestrial analog for the Martian sedimentary rocks at Meridiani Planum.

Acidophilic Halophilic Microorganisms in Fluid Inclusions in Halite from Lake Magic, Western Australia

“…Modern and Permian acid saline lakes and associated environments on Earth, including Lake Magic, are analogues for Mars sedimentary deposits (Benison and LaClair, 2003;Benison, 2006;Benison and Bowen, 2006). Mineralogy and chemistry, sedimentary textures and sedimentary structures, and early diagenetic features on Mars are consistent with those throughout southern Western Australia.…”

Geochemical characteristics of naturally acid and alkaline saline lakes in southern Western Australia

“…In addition, sedimentary rocks in the Meridiani Planum region on Mars were also likely deposited and modified by acid saline fluids (Squyres et al, 2004(Squyres et al, , 2006. These rocks on Mars have mineralogical, sedimentological, and geochemical similarities to both the USA Permian and the modern WA acid systems (Benison and LaClair, 2003;Benison, 2006;Benison and Bowen, 2006;Bowen et al, 2008). The existence of acid saline waters in the geologic past suggest that the system in southern WA may represent more than just a geochemical anomaly, but rather may be an important indicator of larger-scale continental evolution processes.…”

Acid saline lake systems give clues about past environments and the search for life on Mars

“…represents possible, but not clearly documented occurrence. References for Earth analogs include: (1) Chan et al (2004), (2) Kargel (2004), (3) Benison and LaClair(2003),Benison (2006), (4)Fernandez-Remolar et al (2003, (5)Bishop et al (2004), and(6)Grotzinger et al (2005), Langford…”