What are the two heat sources within the earth that causes plate movements ?

The two heat sources within the earth that causes plate movements are as follows:

Explanation:

The earth’s surface faces heat that has two typical sources and is measured in Terawatts unit. The isotopes decay radioactively in the earth’s mantle and crust and produce radiogenic heat in the process.

The inert heat which is dormant inside gets generated due to earth’s past formation process is the primordial heat. So, these two types of sources of heat cause plate movements within the earth crust. Again, there are gravity forces acting which also contribute to such tectonic movements.