Respuesta :
Rocks are grouped according to their formation into three major groups – igneous, sedimentary, and metamorphic rocks
Explanation:
- Based on their formation, rocks are further sub-grouped as:
- Igneous - Intrusive or extrusive
- Sedimentary – Clastic, chemical, or biologic rocks
- Metamorphic - Foliated and non-foliated
- Rocks are also grouped based on their properties like size, shape, texture, chemical composition, permeability, mineralogy, etc.
- Based on properties rocks are sub-grouped as:
- Igneous rocks – coarse or fine-grained; glassy or obsidian; felsic or mafic.
- Sedimentary rocks - conglomerate, sandstone, breccia, shale, siltstone, chalk, crystalline or fossiliferous limestone, gypsum, rock salt etc.
- Metamorphic rocks - Gneiss, hornfels, mylonites, cataclasties, marble, etc.
