Mineralogical consideration of possible microfossils in martian meteorite ALH84001.

The Search for Possible Source Craters for Martian Meteorite Alh84001

ALH84001 is the only martian meteorite currently known with a crystallization age of 4.5 Ga. This ancient age indicates the meteorite must come from the ancient crust of Mars, located primarily in the southern hemisphere of the planet. The 4.56 Ga crystallization age, the 16 Ma ejection, and theoretical models of how material is ejected off Mars were used to identify possible source craters for...

Mechanisms of Formation of Magnetite in Martian Meteorite Alh84001

The origin of organic matter in the Martian meteorite ALH84001.

Stable carbon isotope measurements of the organic matter associated with the carbonate globules and the bulk matrix material in the ALH84001 Martian meteorite indicate that two distinct sources are present in the sample. The delta 13C values for the organic matter associated with the carbonate globules averaged -26% and is attributed to terrestrial contamination. In contrast, the delta 13C valu...

Origins of magnetite nanocrystals in Martian meteorite ALH84001

The Martian meteorite ALH84001 preserves evidence of interaction with aqueous fluids while on Mars in the form of microscopic carbonate disks. These carbonate disks are believed to have precipitated 3.9 Ga ago at beginning of the Noachian epoch on Mars during which both the oldest extant Martian surfaces were formed, and perhaps the earliest global oceans. Intimately associated within and throu...

Kinetic model of carbonate dissolution in Martian meteorite ALH84001

The magnetites and sulfides located in the rims of carbonate globules in the Martian meteorite ALH84001 have been claimed as evidence of past life on Mars. Here, we consider the possibility that the rims were formed by dissolution and reprecipitation of the primary carbonate by the action of water. To estimate the rate of these solution-precipitation reactions a kinetic model of magnesite-sider...