By Alan Richardson

Back in March the Lickey Hills Geo-Champions (LHGC) had conservation sessions clearing the lower faces in the Barnt Green Road (‘Overfold’) Quarry, and the worm burrows in Eachway Lane Quarry.  Later that month, I accompanied Dr David Ray into the Leach Green Lane Quarry.  This quarry, together with the adjoining A38 Rubery Road Cutting, constitutes Birmingham’s only Local Nature Reserve for Geology, although you wouldn’t know by looking at it.  The quarry face lies behind the back gardens of properties in Leach Green Lane.  Long-neglected by the local authority it is heavily overgrown, and used extensively by local residents for the disposal of their domestic waste.  Similarly, the Silurian sequence, once comprehensively exposed in the road cutting, is almost entirely obscured by vegetation, except for a small area where the Ordovician – Silurian unconformity can easily be accessed.  The valiant efforts of the LHGC continue to stem the green tide across this last vestige of geology in the LNR.

David Ray’s research concerns sea-level changes in the Silurian.  He was interested to examine the unconformity across the Leach Green Quarry face to establish the scale of topographic relief that had been buried by sediment during the marine transgression.  While some useful data was recorded, so much of the face is obscured by vegetation that it was not possible to identify a single marker horizon that could be traced for any significant distance.

Nevertheless, given the irregularity of the unconformity at the road cutting, it is striking how even it is in the quarry face.  Where we managed to clear vegetation we were able to document a striking channel structure containing well-rounded pebbles and cobbles.

The Leach Green Lane Quarry Face. The Ordovician Lickey Quartzite is overlain unconformably by Silurian Rubery Sandstone. Towards the left of the exposure, the channel structure can be seen. The picture has been enhanced to clarify the distinction between the two formations. Just above the sawn stump in the quartzite there is a 20cm scale rule.

A close-up of the channel structure in the erosion surface. The highly fractured cobble on the right is about 25cm. The picture has been enhanced to clarify the distinction between the two formations.

In April members of the group carried out conservation work in Warren Lane Quarry, while I applied the pressure washer to structures of interest in Kendal End Quarry at the southern limit of the Lickey Hills Ridge.  A number of fractures here contain a mix of angular fragments of Lickey Quartzite and well-rounded sand grains.  The sedimentary nature of the latter demonstrates that the fissures were open to the surface when the sediment was being deposited.  A similar infilled fissure is evident in the Warren Lane Quarry.  It is most likely that they relate to the unconformity exposed on the summits of Rednal Hill and Bilberry Hill.  The erosion surface here is almost certainly Triassic, and the sedimentary fill in the fissures at the base of the ridge demonstrates that the hills were already a landscape feature at that time.

On 21 April, the LHGC hosted a ‘Champions’ Day’, to which all members of EHT and affiliated Champions groups were invited.  Displays were mounted in the School Room of the Lickey Hills Visitor Centre.  These included photographs to illustrate the work of the LHGC, annotated photographs of the geology, hand specimens and petrological microscopes with which to view thin sections of the local rocks.  However, the main activity of the day was a field excursion covering all the sites of interest in the hills.  There was informed and informative discussion, and the lively exchanges led to new insights into the complexities of the Lickey Quartzite Formation.

This event was then repeated on 15 May, for the benefit of the Malvern U3A group.  Members of both groups were very appreciative, and we are expecting to run a similar event for another geological society next year.

The Champions’ Day event in the Lickey Hills Visitor Centre School Room.

Between scheduled events, the research continues.  The latest findings suggest that the entire sequence in Kendal End Quarry may be inverted.  Watch this space, or better still, join us.

Alan Richardson,

17th May 2024.