EETA79001 b - Olivine Shergottite
Collection:
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Fact sheet

EETA79001 b - Olivine Shergottite

EETA 79001 is a large (7942 gram) meteorite that was recovered during the 1979 ANSMET expedition. It was found on the ice at the Elephant Moraine, near Reckling Peak, Victoria Land, Antarctica. It is an especially important sample because gas inclusions in the glass (seen in the top right of this thin section) in it were found to contain rare gas and nitrogen compositions matching those of the Martian atmosphere as determined by the Viking spacecraft. This was the crucial evidence that the SNC meteorites came from Mars.

EETA 79001 is a shergottite containing two different igneous lithologies separated by an obvious linear contact (visible in our first sample). Lithology A (Rb/Sr 173±10 Ma) is a basaltic melt containing mafic inclusions and clusters of olivine and low-Ca pyroxene in a fine-grained matrix that also contains Cr-spinel, merrilite, Cl-rich apatite, ilmenite and pyrrhotite. The lithology also contains pockets and veinlets of dark glass, which are visible in our second sample. Lithology A has been interpreted as an impact melt and is described as an olivine-phyric shergottite. Lithology B (Rb/Sr 185±25 Ma) is a typical basalt consisting of augite laths in a matrix of pigeonite-augite, maskelynite (after plagioclase feldspar), ülvospinel-ilmenite intergrowths, whitlockite and Cl-apatite.

This description draws on the work of NASA scientist Charles Meyer - compiler of The Mars Meteorite Compendium. A pdf document describing EETA 79001 is available here.

Note that our samples are research specimens and have suffered some damage during their time in electron optical instruments.

Map
-85.76666, 179.383333
Description:
Victoria Land Antarctica
Precision:
Good
About this collection

This collection of meteorites includes Shergottites, Nakhlites and Chassignites (or SNC meteorites) which originate from the surface of the planet Mars.

They carry unique signals of the surface of the planet that allows scientists to study the composition and age of Martian rocks. The collection includes a sample of the famous ALH84001 meteorite, evidence from which was used in 1996 to begin the debate of 'life on Mars?'. 

 

Sample details

Collection: Martian Meteorites
Type
igneous
Category
shergottite achondrite
Rock-forming mineral
olivine
pyroxene
glass
Category guide  
Category Guide
Title
Refers to any word or phrase that appears in the individual rock names. Names are generally descriptive; they allow users to search for broad terms like ‘granite’ as well as more specific names such as ‘breccia’. However, the adjacent descriptions of the specimens captures a wider range of general words and phrases and is a more powerful search tool.
Description
Refers to any word or phrase that appears anywhere in the descriptions of the specimens
Accessory minerals
Minerals that occur in very low abundance in a rock. They are usually not visible with the naked eye and contribute perhapssver, they often dominate the rare elements such as platinum group metals.
Rock-forming minerals
Minerals that make up the bulk of all rock samples and are also the ones used in rock classi?cation.
Timescale
Selecting one or more period, for example 'Jurassic'.
Theme
A term used to group together related samples that are not already gathered into a single Collection. For instance, there is a ‘SW England granites’ theme that includes such rock types as granite, hydrothermal breccia, skarn and vein samples.
Category
A general term used to label a rock sample. It is a useful way of grouping similar samples throughout a collection. Category names are often, but not exclusively, common rock names (e.g. granite, basalt, dolerite, gabbro, greisen, skarn, gneiss, amphibolite, limestone, sandstone).
Owner
The owner of the sample that appears in the collection. For example, NASA owns all the samples that appear in the Moon Rocks collection
We would like to thank the following for the use of this sample: