We were taken back in time - geological time - on our recent
guided walk on Thurstaston beach.
The sandstone that is exposed in higher areas further inland on the Wirral is here 70
feet below the sand. The rock was formed over 200 million years ago at a
latitude of 30 degrees in a desert-like climate. It gradually moved to its present location through the process of continental drift.
More recently, 13,000 years ago, the Irish Sea glacier travelled down from Scotland and through the Lake District until it
encountered the Snowdonia glacier. The glaciers acted like bulldozers, scraping
up a mixture of sand, clay and stones and when the ice melted these were
left as the till (or boulder clay) cliffs on what is now the beach.
Hilary
Davies, our geologist guide, identified stones from Scotland and the Lake
District that had been washed out of the unstable cliffs. Ranger Lynne
Greenstreet helped us identify the shelduck and other birds on the estuary mud
as we completed a fascinating circular walk.
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