The Precambrian
10 July 2014
The Precambrian was a long time ago - 4600 million years ago to about 541 million years ago. In Scotland Precambrian rocks are to be found on the Island of Lewis and on the North West Mainland. In England, there are three small areas of Precambrian rocks. These small areas have been very influential in the history of geology. The rocks are found at the Long Mynd in Shropshire, the Malvern Hills in Worcestershire and at Charnwood Forest in Leicestershire.
The Lewisian Gniess is coarsley crystalline and deeply banded. It’s a rough uncompromising rock that resists what the Atlantic throws at it but it is bare and infertile. Like the climate the rock is harsh. It is home to seals, red throated divers, bonxies, starlings, sky larks, eagles, twites and a multitude of seabirds. At 3500 million years these are the oldest rocks in Britain.
Charnwood is the site where a school boy, called Roger Mason, in 1957, discovered one of the Earth’s oldest fossils, namely Charnia masoni. Roger was immortalised and Seapens (for this was the fossil) hit the headlines. Charnwood in now the site of the National Forest which is an environmental project to create a 200 square mile forest.
The Malvern Hills exist because the Precambrian rocks there have resisted erosion better than softer and younger rocks. The hills are low by Scottish standards but they afford magnificent views of the vale of Evesham to the east and Herefordshire and Wales to the west. To the east fertile lands grow fruit and vegetables. In spring the orchards are covered in blossom and picturesque villages abound. To the west, green hills roll their way to Wales where Offa’s Dyke delineates the border. The Malverns are equipped with networks of magnificent paths maintained by the Malvern Conservators. They were a favourite haunt of the composer, Elgar and are now a favourite spot for launching para gliders and hang gliders. When the weather conditions are favourable twenty or more para gliders launch from Pinnacle hill and ride the ridge wave created by the hills. They may fly for as long as they want around the hills and then land in a designated field at the bottom or head off to distant destinations such as Aberystwyth.
The Long Mynd lies further to the north in Shropshire. Again the hard rocks have resulted in hills and here too, is a favourite place for para gliding. Walkers on the Long Mynd could be forgiven for imagining that they are in Scotland. The hills are covered in heather and are cleft by deep valleys such as Carding Mill Valley. Church Stretton nestles beneath the hills and invites the walker to head west. If you continue west the mysterious Stiperstones beckon with their tiny lanes and the Shropshire Way leads to big skies full of bird song.
Thank you Precambrian rocks. You are old but unbowed and beautiful. You were laid down before most multicellular life had evolved but had the sense to wait.
Papillon