Hidden Earth 2023

Hot stuff. Looking for hypogenic caves in Southwest England

30 minute Lecture|Andy Farrant

Abstract

The Bristol-Bath area is host to several thermal springs, including the famous Roman Baths in Bath where about 1.3 million litres of water flow from the springs every day at a temperature of around 40°C. Less well-known springs occur in the Avon Gorge in Bristol. These springs are the outlet for deep hypogenic conduit systems within the Carboniferous limestones that descend to a depth of 2.5 km beneath the North Somerset coalfield. Given the geological setting, it seems likely that relict hypogenic conduit systems should be present with the limestones in the region. Yet until recently, very few relict hypogene caves were known in the area, the obvious exception being Pen Park Hole in Bristol. A reappraisal of various caves and mines in southwest England has revealed a host of other possible hypogenic caves, including some surprising sites. This talk will discuss each of these sites and address the formation of hypogenic caves in the region, why they occur where they do and what this means for discovering new caves in the region