Question:
The name of an igneous rock having a modal composition of 55% olivine, 40% orthopyroxene and 5% plagioclase, as per the IUGS classification scheme, is
The name of an igneous rock having a modal composition of 55% olivine, 40% orthopyroxene and 5% plagioclase, as per the IUGS classification scheme, is
Updated On: Feb 10, 2025
- gabbro
- $β^+ (positron) decay
- lherzolite
- harzburgite
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The Correct Option is D
Solution and Explanation
According to the IUGS classification of igneous rocks, harzburgite is characterized by a composition dominated by olivine and orthopyroxene. The given rock composition, with 55% olivine, 40% orthopyroxene, and 5% plagioclase, fits the definition of harzburgite.
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