Top 5 Facts: Earth’s crust

1. Uniformitarianism – 11th Century Persian scholar Avicenna proposed that the Earth’s crust’s rock formation occurs through processes that have operated uniformly throughout history.

2. Causeway clash – In the late-18th Century two groups of scholars fought over how Giant’s Causeway was formed, one believing from volcanic activity, the other sedimentary.

3. Ouroboros – It was geologist James Hutton who first raised the idea of the rock cycle, the process where rocks are eroded, compacted, compressed and melted before cooling into new rocks.

4. Tried and tested – Standard geological tools consist of a rock hammer, chisels, a pocket knife and a storage container. These tools have not really changed in over 400 years.

5. Creator – Volcanoes are one of the predominant creators of new rocks, formed from the cooling and crystallisation of magma. These rocks are igneous varieties.