pelitic rock

geology

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July 1, 2026

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Pelitic rocks, also known as pelites, are a category of sedimentary rocks composed of fine-grained particles, primarily clay or mud. These rocks are abundant, making up a significant portion of Earth's sedimentary rock column.12

Pelites include siltstone, claystone, and mudstone, with shale being a specific type of mudrock that exhibits lamination or fissility. While often formed from weathered rock material, pelites can also contain chemically precipitated cement and organic matter. Their fine grain size influences their properties, typically indicating deposition in low-energy environments where water movement is minimal.23

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metamorphic rock
Classification into four chemical systems
Pelitic rocks are derived from mudstone (shale) protoliths and are rich in potassium (K), aluminum (Al), silicon (Si), iron (Fe), magnesium (Mg), and water (H₂O), with lesser amounts of manganese (Mn), titanium (Ti), calcium (Ca), and other
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Pelitic rocks are derived from mudstone (shale) protoliths and are rich in potassium (K), aluminum (Al), silicon (Si), iron (Fe), magnesium (Mg), and water (H₂O), with lesser amounts of manganese (Mn), titanium (Ti), calcium (Ca), and other
Read More