Aggregates of Herefordshire

Herefordshire Geological Succession

Geological Time

Geological time is divided into eons, eras, periods, epochs and ages, with eons representing the largest stretches of time (500 million years or more). Each eon is subdivided into eras, which in turn are divided into periods etc… This nomenclature ends with ‘ages’, which represent the smallest increments of geological time, on the order of a few hundred thousand years.

Rocks of similar age can grouped together and placed into a geological succession, where they lie in between rock units of greater and lesser age. As geology varies across distances, these geological successions are only relevant to a specific geographical area. Geologists can get some idea of what processes were taking place in Herefordshire over millions of years, by looking at what types of rocks were forming at different times in the geological succession. The most useful subdivisions of geological time are periods, epochs and ages, as rocks dated to these resolutions can give both general and detailed information on the ancient environment.

In this geological succession, periods and epochs are used to describe the older geological succession (Precambrian – Jurassic) that is seen in Herefordshire. The most recent geological period (the Quaternary) is described in terms of period and age, as the detail preserved within these young rocks and sediments allows for more detailed interpretation.

Site Examples:

Bartestree Quarry

Beech Cottage Quarry

Bircher Common – Welshman’s Lane

Blackbush Farm

Brockhill Farm Quarry

Coneygree Wood Quarry

Croft Castle Quarries

Fowlet Farm Quarry

Frith Barn Quarry

Gardiners Quarry

Great Corras Quarry

Gullet Main Quarry

Gullet Pass Pit

Gullet Top Quarry

Hackley Farm 1

Haffield House Quarry

Leinthall Earls Quarry

Linton Quarry

Lord’s Wood Quarry

May Hill Common Quarry

Nash Quarry

New House Farm Quarry

Quarry north of King Arthur’s Cave

Rudge End Quarry

Seven Sisters Cliff Quarries

Shobdon Quarry

Slasher’s Quarry

Sutton Walls Hill Fort

Trippleton Lane

Upper Hall Farm Quarry and Grasslands

Upper Lyde Quarry

Whitman’s Hill Quarry

Wordell’s Farm Quarry

Reproduced with the permission of the British Geological Survey © NERC. All Rights Reserved. Based upon information in the BGS Lexicon and the BGS memoir ‘Geology of the country between Hereford and Leominster, 1:50,000 scale sheet 198‘, with the permission of the British Geological Survey