* Igneous rocks form from the cooling and solidification of molten rock (magma or lava).
* Sedimentary rocks form from the accumulation and cementation of sediments. These sediments are derived from the weathering and erosion of pre-existing rocks (igneous, metamorphic, or even other sedimentary rocks).
The Transformation Process:
To transform a sedimentary rock into an igneous rock, it must go through a series of events:
1. Burial and Heat: The sedimentary rock needs to be buried deep within the Earth's crust, where it is subjected to intense heat and pressure.
2. Melting: The heat eventually causes the sedimentary rock to melt, transforming it into magma.
3. Cooling and Crystallization: The magma then rises and cools, either intrusively (underground) or extrusively (on the surface), forming igneous rocks.
In summary:
Sedimentary rocks are not the starting material for igneous rocks. The transformation from sedimentary to igneous requires melting and then cooling, creating a completely new rock type.
