A proposed conceptual model for the genesis of the Derbyshire thermal springs
Ten thermal springs occur in seven centres in Derbyshire, England with temperatures up to 27.5oC
compared with an ambient groundwater temperature of about 9oC. The springs discharge from a
karstic Dinantian limestone aquifer along the boundary with the overlying Namurian strata
around the edge of a regional dome structure. The water is heated by deep circulation to as
much as 1km with the hottest spring being at Buxton spring where the water is 5,000 years old. A
comparison of flow data from the Buxton spring with groundwater hydrographs shows seasonality in the
thermal flows suggesting that the loading effects produced by recharge are transmitted through this
deep aquifer system. From a review of the geological history and the hydrogeology and the use of
measurements on the Buxton spring it is suggested that the thermal flow system may have its roots
in ancient convection cells possibly established in the deeply buried aquifer in late
Carboniferous-Lower Permian times. Subareal erosion during the Pliocene removed the impermeable
cap rocks and allowed both the thermally heated water to form warm springs and this deep groundwater
circulation to be recharged by meteoric waters. The location of the individual springs is likely to date
from the down-cutting during the Upper Pleistocene that formed the modern river valley topography.
Reference
Brassington, F.C. (2007) A proposed conceptual model for the
genesis of the Derbyshire thermal waters. QJEGH, 40, 35 - 46
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