Northern Rocks: Shetland

Neville Martin (UK) Shetland is famous for many things including ponies, knitwear, sheep and sheepdogs, birdlife and fishing. It is less well known for being an excellent attraction for the geologist or that it is currently going through the process of qualifying for European and World Geopark recognition. The rocks of Shetland are too old for fossils with the exception of some fish and aquatic plant fossils at the southern and western extremities. However, what it lacks in fossils it more than makes up for in an abundant variety of minerals and geological structures and, while looking for minerals, the geologist can enjoy some of the most spectacular seascape in the UK. In addition, the islands have a long history of mineral extraction and there has been talk of possible, future platinum and gold mining. Fig. 1. Old Red Sandstone Cliffs, Bard Bressay and Noss. One of the reasons for the geological diversity is that the Great Glen Fault, which formed Loch Ness, also manifests itself in Shetland. This gives rise to a displacement of some 60 to 80km, such that there is a distinct difference between East and West Shetland. The landscape is also the result of sculpturing by glaciers and the sea. The many submerged, glacial valleys are called “voes”, the largest of which is Sullom Voe, the site of the oil terminal where oil from north, east and west of Shetland is landed. The shelter provided by such a large voe (which is sea loch) made it … Read More

To access this post, you must purchase Annual subscription, 12 Month Subscription or Monthly subscription.

Seeing into the ‘Stone Age’: The stone tools of early man

Bob Markham (UK) In the early part of his evolution, man made great use of rock and stone to assist him in his activities. The term ‘Stone Age’ has been given to the period of time during which stone was the main material used for the manufacture of functional tools for daily life. It is generally thought to have commenced about 3.3Ma and was the time when man firmly established his position on earth as a ‘tool-using’ mammal. However, it should be remembered that stone was not the only material used for this purpose. More perishable materials, such as wood, reeds, bone and antler, were also used, but very few of these materials have survived to be found today (but see the box: Non-stone tools). Non-stone toolsA notable exception to the general rule that non-stone tools have not been preserved is the Palaeolithic wooden spear shaft that was recovered in 1911 from a site in Clacton in Essex. At 400,000 years old, the yew-wood spear is the oldest, wooden artefact that is known to have been found in the UK (see http://piclib.nhm.ac.uk/results.asp?image=001066).A number of wooden spears dating from 380,000 to 400,000 years ago were also recovered between 1994 and 1998 from an open-cast coal mine in Germany (see https://en.wikipedia.org/wiki/Schoningen_Spears). Other items are found from time to time from peat-bog conditions, which offer the most favourable medium for the preservation of such material.The stones used to make tools Being a non-perishable material, stone has survived the ravages of time and is … Read More

To access this post, you must purchase Annual subscription, 12 Month Subscription or Monthly subscription.