There are some exceptions, such as tree trunks surrounded by lava and preserved as casts, but these are rare. Metamorphic rock is formed when existing rock is transformed under high heat and pressure, ...

NASA’s Perseverance rover has captured an image of a never-before-seen Martian rock formation that scientists believe could ...

Heat and/or pressure will cause the elements in the original rock to react and re-form. Metamorphic rocks are highly resistant to erosion and are often used in building materials.

Sedimentary rocks are formed by small rock pieces which are transported by rivers and laid down in layers. Chalk is a sedimentary rock. Metamorphic rocks are formed when another rock is under heat ...