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Home » Articles » Geology - the Proterozoic EraGeology - the Proterozoic Era
Rocks and fossils dating from the Proterozoic Era.
Rocks and fossils dating from the Proterozoic Era.
The oldest rocks found in Wales today are about 700 million years ago, and rocks of this age probably underlie most of the country. Most of these rocks were formed by subduction processes as oceanic crust was destroyed on the outer margins of the ancient continent of Gondwanaland. Magmatic activity produced volcanic rocks, and at deeper levels, granite intrusions, and the erosion of these rocks formed sediments. Plate tectonic processes resulted in extensive and repeated faulting. The earliest, very simple forms of life, have been found as fossils 3.4 billion years old, but no record of these exist in Welsh rocks. Our earliest fossils are around 570 million years old and resemble jellyfish. They lived in the shallow seas bordering Gondwanaland.
