The alternate heating and cooling of rocks result in

The alternate heating and cooling of rocks can result in a process called thermal stress. When rocks are subjected to changes in temperature, the different layers of the rock expand and contract at different rates. This can cause stress on the rock and over time, it can lead to cracking and breaking, a process known as fragmentation. This can happen as a result of volcanic activity, tectonic activity, or weathering and erosion. The rocks can also undergo cycles of heating and cooling and this can result in the formation of fractures and joints. In some cases, the heat can be so intense that it causes the rocks to melt, resulting in the formation of magma and new igneous rocks.