Holme Park and Trowbarrow Quarries
Leader: Carolina Goodship. Cumbria GeoConservation Group
We will be visiting two very different sites in and around the Arnside & Silverdale National Landscape to examine a variety of geological features in the Lower Carboniferous limestones, including their lithology, fossil record, palaeokarst, Quaternary karst features and structural geology. In the morning, we will visit Holme Park Quarry. This is a working quarry operated by Holcim UK and our guide will be the quarry manager. The quarry extracts Lower Carboniferous Urswick Limestone which is crushed to produce a high-quality aggregate. The shallow dip of the limestone strata provides an excellent opportunity to see the stratigraphic sequence of the Urswick limestone in its full unweathered technicolour glory. If have time, we’ll include a short visit to see limestone pavement on an island in the middle of the quarry. The island is a nature reserve managed by the Cumbria Wildlife Trust. In the afternoon, we will visit Trowbarrow, near Silverdale. This disused quarry is a designated geological SSSI and ,local nature reserve, managed by the Arnside & Silverdale National Landscape. In addition to its outstanding geology, the quarry supports a rich and varied fauna and flora, including several species of orchids. Trowbarrow is a key locality to study Urswick limestone geology and its ancient life. The site displays a wide variety of limestone types, including evidence of emergence and outstanding examples of palaeokarst exposures. The limestone hosts a rich fossil community, especially foraminifera (tiny single-celled organisms with shells). Macro fossils such as corals and brachiopods are also present, along with excellent exposures of Thalassinoides trace fossils. Unlike the shallow dipping beds at Holme Park Quarry, here the beds are oriented vertically – effects of the Variscan deformation known locally as the “Silverdale Disturbance.”
Contact the LGA secretary on lga.sec@btinternet.com for more information if you wish to attend.