Brinkmarsh Quarry

Also within

Gloucestershire County

Condition (Natural England)

Geology & landscape

Mining / Industrial: Quarry · Geological Period: Silurian

Description

Area, 0.5 ha. 1.2 ac. Description This is an important locality for the study of Silurian palaeontology and palaeogeography, which has been well known to geologists for over 150 years. During the early Wenlock part of Silurian time, some 410 million years ago, Wales and western England lay beneath an extensive sea in which a series of marine sediments were laid down. Brinkmarsh Quarry provides exposures of richly fossiliferous shales and sandy limestones belonging to a subdivision of the Wenlock Series known as the Brinkmarsh Formation, named after this area. The site is the source of numerous fossils belonging to many phyla and large numbers of fossils from the quarry are contained within major museum collections throughout the country, for many of these fossils Brinkmarsh is the type locality, the site from which a particular species was first recognised and described and it thus occupies a very important place in the study of palaeontology. Recently it has yielded unique occurrences of fossil crustacea known as beyrichiid ostracods and of thelodont fish scales. The composition of the rocks making up the Brinkmarsh Beds is also very important. Here, the rocks consist of sandy shales and limestones whereas elsewhere in the Welsh Borderlands rocks of similar age are developed as much purer shales and limestones. This significant difference is of great value in enabling geologists to reconstruct the detailed palaeogeography of southern Britain during early Wenlock times. The combination of these palaeontological and sedimentological aspects endows Brinkmarsh Quarry with very great importance to the study of Silurian geology.