plagiogranite

geology

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July 1, 2026

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Plagiogranite is a type of igneous rock, specifically a plutonic rock, meaning it forms from magma that cools slowly beneath the Earth's surface. It is characterized by its composition, which is rich in quartz and feldspar. Plagiogranite is distinguished from granite by having more plagioclase feldspar than alkali feldspar. Other minerals commonly found in plagiogranite include hornblende and biotite. These rocks are typically medium to coarse-grained and can be darker in color than granite due to their higher plagioclase content. Plagiogranite is closely related to granodiorite and granite in terms of its formation and occurrence.123

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oceanic crust
…this layer includes pods of plagiogranite, a differentiated rock richer in silica than gabbro. The lower gabbro layer has a stratified structure and evidently represents the floor or sides of the magma chamber. This layered structure is called cumulate, meaning that the layers (which measure up to several metres thick)…
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…this layer includes pods of plagiogranite, a differentiated rock richer in silica than gabbro. The lower gabbro layer has a stratified structure and evidently represents the floor or sides of the magma chamber. This layered structure is called cumulate, meaning that the layers (which measure up to several metres thick)…
Read More