Rocks that have been altered by compression are known as metamorphic rocks. When pre-existing rocks, called protoliths, are exposed to high temperatures, pressures, and/or chemical reactions, their crystal structures and chemical compositions can change, resulting in the formation of metamorphic rocks. Here are some examples of rocks that form due to compression:

Slate: Slate is a fine-grained metamorphic rock that forms when sedimentary rocks, such as shale, undergo compression and low-grade metamorphism. The pressure causes the minerals in the original rock to recrystallize and align, resulting in a distinctive layered or foliated appearance.

Quartzite: Quartzite is a hard, compact metamorphic rock that forms from the recrystallization of sandstone. The heat and pressure involved in metamorphism cause the quartz grains in the sandstone to fuse together, forming a massive interlocking structure.

Marble: Marble is a metamorphic rock formed when limestone, a sedimentary rock composed mostly of calcium carbonate (calcite), is subjected to high temperatures and pressures. This type of metamorphism leads to the recrystallization of calcite and the formation of interlocking crystals.

Gneiss: Gneiss is a coarse-grained metamorphic rock formed from the compression of igneous or sedimentary rocks. The high temperatures and pressures during metamorphism result in the recrystallization and alignment of minerals within the rock, creating a distinct banded or layered structure.

Phyllite: Phyllite is a fine-grained metamorphic rock that forms when rocks like slate undergo further compression and higher-grade metamorphism. It has a lustrous sheen due to the growth of new mineral grains within the rock.

These are just a few examples of metamorphic rocks formed due to compression. The type of metamorphic rock produced depends on the original rock composition, the degree of temperature and pressure, and the fluids involved in the metamorphic process.