Identify rock Essay Example | Topics and Well Written Essays - 250 words - 1

Identify rock - Essay Example The term ‘Eucrite’ has now become obsolete for the igneous rock known as bytownite-gabbro that is formed in the Earth’s crust. It is also a term that was mostly used for the Paleogene rocks found in Scotland. Eucrites are a part of the HED meteorite clan that consists of over a hundred different meteorites. This is because they mainly originate from the surface of an asteroid known as 4 Vesta (Binzel, & Xu, 1993). They are achindritic stony meteorites and are the most distinct of the clan. This type of rock also consists of the basaltic rock found in the same asteroid. The rocks are mostly made of pegeonite, Calcium-poor pyroxene, and lastly the anorthite (Calcium-rich plagioclase). The above composition of the different rocks is what requires that the eucrites be divided into several groups. The first category is the cumulate eucrites. This type of rock is rare and is thought to originate from the interior of the 4 Vesta, from its crust that is, and deep within its solidified magma (Binzel, & Xu, 1993). Polymict eucrites, on the other hand, are regolith breccias. This type of rocks is also very rare and consist of mostly eucrite segments and less that 10% of a type of howardites known as diogenite. The structure is also as coarse as most other rocks made of silica (Binzel, & Xu, 1993). Lastly, there are the most common type of eucrites, which bears almost all the above rocks characteristics, spongy and having alternating rough and smooth segments. They are known as the Non-cumulate