Introduction to the Geology of Martley and the Teme Valley in Worcestershire
Martley parish lies along and to the east of the River Teme in west Worcestershire. The river is a SSSI along its whole length from where it rises in the Kerry Hills in Wales to where it joins the River Severn just south of Worcester. By curious chance the geology of the parish is exceptionally varied and unique in southern Britain. No fewer than seven distinct geological periods, spanning 700 million years of time are to be found within our boundaries. The jewel in the crown, Martley Rock, now a developed visitor site, exhibits five periods in an area approximately 60m x 15m. At this old gravel pit, first recorded by Sir Roderick Murchison in 1839 and set in beautiful countryside with lovely views to the north, there are interpretation boards and leaflets to help explain what is on view. On display here is the most northern exposure of Malvern Complex (Pre-Cambrian ) rock (age +-700Million Years), Cambrian Quartzite (age est’d 500MY), Silurian (Raglan Mudstone 418MY, Carboniferous (Halesowen Formation Coal Measures, 308MY) and Triassic (230MY).
A fault of great significance in the shaping of the current landscape over many hundreds of millions of years, theEast Malvernfault, runs through the Martley Rock site. Visitors can see this dividing line between Silurian aged rocks and to the east, the red Triassic, itself a common feature in the region, with outcrops and much used as a building material.
Other locations in the parish provide very good exposures of Permian Breccia (270MYa), a rubble left over from the erosion of high mountains to the north, and limestone of Silurian age filled with fossils.
In the Teme valley, only 2-3 miles from Martley, is one of the largest exposures in the country of Travertine rock, often known as Tufa, laid down in the valley since the last ice age. Tufa deposits form from the evaporation of water that contains a high degree of dissolved calcium carbonate, itself the result of slightly acid rain falling on our hills, permeating the limestone and dissolving it. The process continues today and is easily visible at this deposit.
At similar distance, there is an igneous intrusion (dolerite) that forced its way into cracks in the surrounding Silurian mudstone. This site is known as the Brockhill Dyke and because of the very high temperature of the igneous, its heat affected the rocks that it came into contact with. This is known as a chilled margin and is a fine example, well worth seeing, along with onion skin weathering of the igneous outcrop.
There is coal in the TemeValley, with many hundreds of bell pits and shafts a few miles north of Martley, operating until the 1970’s. In the parish there are tales of coal mining (very poor quality and quantity) on Berrow Hill and on the hill there are two or three depressions–putative coal pits–from ages ago.
The Martley Geology Project
The Teme Valley Geological Society was formed in 2011 and successfully secured funding as part of the LEADER programme, to develop the unique geology that exists in the parish of Martley.
The project work is:
- To audit the geology of Martley and to produce documents as a visible and accessible record of the findings. To give an idea of the scale of this part of the project, there are over 40 geological sites that have been investigated.
- To develop Martley Rock site as a visitor attraction with suitable interpretation materials and including walkways, safety railings, car park.
- Production of educational packs for visiting learning groups
- To sponsor courses in geology for anyone interested
- To initiate geo tourism in the parish
The project commenced 1st August 2011, is on schedule and will finish at the end of 2012.
Teme Valley Geological Society website and blog