Limestone Clints & Grykes walk - Lancashire Wildlife

The quarrying activity between 1857 and1959 reveals a glimpse into the 300million-year geological history of the site.A more detailed leaflet about Trowbarrow– the history, geology, wildlife and rockclimbs - is available from the AONBOffice.Exit the quarry following the track downto Moss Lane. 3You are now walking down a slightincline following an old tramway, whichtransported limestone from the quarryto the limeworks. The weight of the fullwagons transporting the quarried limestoneby gravity down the incline would haul theempty ones back to the top.On reaching the road turn right and carryon past the cottages for 600m until youreach a low gate across the road. You arenow entering Gait Barrows NationalNature Reserve (NNR). Follow the trackstraight on, until you reach the boardwalk.The stretch of water on your left isHawes Water, 4 with Challan Hallon the far side.Trowbarrow (LNR)The process is accelerated by carbonicacid (formed from dissolved atmosphericcarbon dioxide) and organic acids(a by-product of decaying vegetation).The limestone is slowly ‘dissolved’ overmillions of years, as the water picks outvertical lines of weakness in the rockbelow the surface resulting in a seriesof underground streams and caverns.Over millions of years the cavern walls/ceilings weaken and eventually collapse.The debris is gouged out by subsequentglaciers. Sometimes several ‘dolines’,often referred to as ‘sink-holes’, downwhich concentrated surface watersproceed underground, can coalesceand form a ‘uvala’ of which Hawes Waterbasin is a good example.Solution DolineHawes WaterAbout 2 million years ago the worldclimate cooled dramatically, heraldingthe start of a series of ice ages.Intermittent milder periods (inter-glacial)resulted in torrential melt water. The actionof both ice and melt water moulded muchof the landscape we see today.The Hawes Water basin was formed bysolutional activity removing the limestone,which is both permeable and soluble.Collapsed Doline