The small earthquakes that shook the ground near Blackpool in April and May were probably caused by experimental drilling operations in the area.

An independent report carried out for energy firm Cuadrilla said that the company’s search for shale gas in Lancashire was probably to blame for the quakes. The report blamed an unusual mix of factors and said that it was unlikely to happen again.

Shale gas is the same as the methane that many of you use to heat your homes and to cook food with. It is harder to extract from the ground because it is trapped in shale rocks, which need to be split open to release the gas. This is done by pumping lots of water, sand and chemicals into the rocks.

The process is known as hydraulic fracturing, or ‘fracking’, and causes some arguments. Protesters in the US have blamed fracking for polluting water supplies, while other scientists have said that the technology is so new that its risks are not fully understood yet. Many of the chemicals used in the process can be toxic or carcinogenic (causing cancer).

However, one of the main issues that critics raise is that the energy industry is starting to invest huge amounts of money in shale gas extraction. Many scientists and protesters would prefer it if money was invested in greener energy sources that don’t pose potential hazards to human health or crucial water supplies.

The video report below explains more about what fracking is. Leave some comments below and let us know what you think.