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Lyth Hill Heritage Celebration 2005
Grassland walk June 2005
A Year on Lyth Hill
Woodland Ways and Settlement - Part One
Woodland Ways and Settlement - Part Two
Wildlife Detectives on Lyth Hill
Shrewsbury Wildlife Trust
Mary Webb and Spring Cottage, Lyth Hill. 1916-1927
Birds on Lyth Hill
Rock Makes the Lyth Hill Landscape
Lyth Hill Heritage Celebrations 2006
Geology Trail Training Event May 7th 2006
Fungus foray on Lyth Hill October 2005
Groups involved in the Lyth Hill Heritage Group
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Rock Makes the Lyth Hill Landscape
Location: Shropshire
The landscape is generally a reflection of the underlying rocks, but it is very easy to see on Lyth Hill just how this applies in detail.
The Lyth Hill ridge is part of the north-easterly extension of the up-folded line of ancient rocks (Precambrian, about 550 million years old) which connects the Long Mynd to the south west with Haughmond Hill to the north east. These are sedimentary rocks, laid down in deltas or very shallow basins at the foot of a mountain range made up of the even older Precambrian volcanic rocks.
Some 540 million years ago the whole Precambrian sequence was folded by earth movements into a vast syncline (U shaped fold). Pontesford and Earl’s Hills, are part of the western limb of this fold. The Wrekin and Stretton Hills are remnants of the eastern limb. Between the two, the rocks of the Long Mynd, Bayston Hill and Haughmond are so tightly folded as to crop out almost vertically at the surface.
The rocks that have survived erosion over the millennia are the coarser beds of sandstone, gritstone and conglomerate (nature’s concrete). These are well seen in the crag immediately below the western car park and view point.
The steep southern scarp face of Lyth Hill exposes a number of crags and a substantial section of natural cliff – now clearly visible thanks to tree clearing for the electricity cable. These follow the line of the Lyth Hill Fault, a break in the rocks which has displaced the line of the original beds, bringing the harder coarse sediments against less resistant finer sediments.
These natural cliffs of bare, acidic rock provide one of the most easterly natural habitats for a plant of essentially western distribution, Navelwort, so called from the way in which its stalk attaches to the middle of the rounded leaves. In some places the rocks are also covered in distinctive lichens and mosses.
Apart from the natural interest of the rock beneath it, Lyth Hill also provides the most splendid viewpoint from which to understand the geology of the entire area of the South Shropshire Hills. The geological evolution of the hills can be traced from the oldest Precambrian of the Wrekin and Pontesford Hill, through the period when we were on the edge of a great ocean out to the west, with limestones and other shallow water sediments to the east, giving Wenlock Edge and the Stiperstones.
In recent geological time the glaciers of the last Ice Age probably swept over Lyth Hill and on towards the Stretton Gap. The sand and gravel left behind as they melted can be seen in the quarries of Condover and Dorrington in the middle distance.
All of this will soon be explained more fully in a new “Geotrail” covering Lyth Hill and Sharpstone Quarry (in the northern extension of the same ridge), whilst it is hoped to portray the view in a new toposcope.
A Geoconservation Management report has been prepared by the Shropshire Geological Society for the Shropshire County Council Countryside Service to provide advice on maintaining the most important rock exposures. These are scheduled as Regionally Important Geological Sites (RIGS).
Those wanting further information regarding the geology of Lyth Hill should look up the Shropshire Geological Society’s web site at www.shropshiregeology.org.uk or contact the SGS Project Officer by e-mail at rigs@shropshiregeology.org.uk or on 01547 530660.
Pictures:
Top The crag below the main viewpoint – the coarse conglomerate bands can be seen running almost straight up and down the slope.
Middle Natural cliffs at the west end of the scarp slope follow the line of the Lyth Hill Fault and are home to the acid, rock-loving Navelwort.
Bottom Navelwort in winter.
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