Belgica 7904 meteorite, Queen Maud Land, Eastern Antarctica, Antarcticai

Regional Level Types
Belgica 7904 meteorite	Meteorite Fall Location
Queen Maud Land	Region
Eastern Antarctica	Region
Antarctica	Continent

Carbonaceous Chondrite, ungrouped [C2-ung; S1: W1]
Find, 1979; 1.234 kg

In 1979 a somewhat weathered meteorite with a still nearly intact fusion crust was recovered in Eastern Antarctica. The meteorite seemed to most resemble members of the CM carbonaceous chondrite class and, indeed, Belgica 7904 was listed as a CM meteorite two decades later in the Catalogue of Meteorites published in 2000. Belgica shares a number of characteristics with CM meteorites. Belgica 7904 contains moderately small chondrules rich in Olivine and other silicates, tiny crystals and mineral fragments, and a very fine-grained, microscopic and disparate mix of crystalline and glassy material rich in intertwined phyllosilicates. However, its bulk chemisty, isotopic ratios, and mineralogical features do not quite match those of the CM group or any other defined Carbonaceous Chondrite group.

At some very early epoch the moderately high temperature components found in its chondrules (e.g. Forsterite, Enstatite) were altered and partially hydrated by the admixture of new, less reduced constituents. Such phyllosilicate material, however, was once again dehydrated by later heating events (perhaps only one). Today we do not know whether Belgica 7904 is the sole terrestrial representative of an unknown homeworld or, perhaps, one of a very small subgroup. For now it is listed as one of the small number of ‘Ungrouped Carbonaceous Chondrites.’

Much of what we know about Beligica 7904 was summarized in two reviews presented two decades ago (Ikeda,1992; Kimura & Ikeda, 1992). However, intriguing details about its tiny components and microstructures are still being reported even today.

Other Regions, Features and Areas containing this locality

References