The temperature and pressure on the earth's surface is lower than that below the earth's surface. Generally, temperature and pressure increases as you move/dig down the earth's surface. This increase in temperature and pressure causes the earth's sediment (below the earth surface) to form a compact solid rock - this process is known as lithification.
Transduction. Transudction is the process where foreign DNA is introduced into a cell by a virus or viral vector. An example would be a viral transfer from one bacteria to another.
