Metamorphic rocks start as other rocks that are deeply buried and changed by intense heat, pressure or both. This transformation alters their minerals, texture and structure. Examples include marble (from limestone) and slate (from shale).
These rocks have a solid appearance with interlocking crystals or grains, often forming in regions of mountain-building or deep crustal activity
Whether you’re walking across solid rock or examining a diagram of Earth’s layers, these rock types explain a lot about our planet’s past.
From the Giant’s Causeway of Northern Ireland (a famous igneous formation) to coal deposits buried in ancient swamps, the formation and classification of rocks reveal a dynamic Earth in motion.
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