Haffield House Quarry

Exposed Units: Clent Formation (Haffield Breccia)

This is the type section for the Clent Formation, known locally as the Haffield Breccia Formation, at the base of the Permo-Triassic succession. The breccia forms a marked unconformity on Silurian and Malvern Complex rocks and forms a pronounced ridge between The Vineyard and the Glynch Brook Valley.

At this site, the Formation comprises poorly sorted, hematite-coated, subangular clasts of Malverns Complex rocks (mainly sheared, pinkish brown granite and dark green diorite) and greenish grey and purple-brown May Hill Sandstone and siltstone set in a matrix of purple to dark red brown, sandy siltstone and mudstone.  The clasts are mostly less than 10cm across, but blocks up to 1m in diameter have been recorded.  The sediments are generally well bedded, some beds having erosive bases scouring down as much as 30cm into the underlying sediments.  In some of the southernmost exposures, the beds are less than 8 cm thick, many consisting of a thin basal breccia fining upwards into coarse-grained sandstone with only a few small clasts.

No flora or fauna has been recorded from the Haffield Breccia, but by comparison with the Clent Formation elsewhere in the West Midlands, a tentative age of Lower Permian is suggested.

Photos

Rock face at the Haffield House Quarry showing well beddd, pink-coloured sedimentary units of the Clent Formation (Haffield Breccia).

The breccias at Haffield House Quarry, showing angular blocks set in a pink matrix of finer-grained material.

A close-up of the breccia at Haffield House Quarry, showing a large range in clast size.

References

WORSSAM, BC, ELLISON, RA and MOORLOCK, BSP. 1989. ‘Geology of the country around Tewkesbury’. Memoir of the British Geological Survey GB, Sheet 216, 57pp.

March 2011