Английская Википедия:Brachinite

Материал из Онлайн справочника
Перейти к навигацииПерейти к поиску

Шаблон:Short description

Файл:NWA 3151 meteorite, brachinite.jpg
Slice of the Northwest Africa 3151 meteorite.

Brachinites are a group of meteorites that are classified either as primitive achondrites or as asteroidal achondrites. Like all primitive achondrites, they have similarities with chondrites and achondrites. Brachinites contain 74 to 98% (volume) olivine.

Naming and history

Brachinites are named after the Brachina meteorite, the type specimen of this group, which in turn is named after Brachina, South Australia.[1]

Description

Brachinites consist almost entirely of olivine (74 to 98% by volume). Other minerals include plagioclase (6.7 to 12.9%), iron sulfides (1.8 to 4.0%), clinopyroxene (1.5 to 8.2%) and orthopyroxene (0 to 2.4%). Trace minerals include phosphates and meteoritic iron. The only deviation from chondrites is the very high olivine/orthopyroxene ratio.[2]

Specimens

As of 2022, there were 56 meteorites classified as brachinites.[3] A notable example is the type specimen, the Brachina meteorite.

See also

References

Шаблон:Reflist

Шаблон:Meteorites