United Kingdom II
Lulworth Cove, Dorset, England
Stephen Kerce, Collector On September 10, 2010, I left London with my friends Phillip and Leila
for a weekend trip through Dorset. It was all to be new to me, and part
of it was for me to retrace some of the steps my Mother had travelled
with these same friends years before. But our first stop was put on the
itinerary by me: Lulworth Cove, the eastern gateway to the Jurassic
coast of south England.
Part of the fascination of Gary's Common Ground project for me has
always been the subtheme of geological change and the evolution of life
on earth. So I definitely wanted to collect some soil for the project on
the Jurassic Coast. This section of the coastline is a UNESCO World
Heritage Site, and stretches for almost 100 miles from Old Harry Rocks
in Dorset in the west to Orcombe Point in Devon in the east. It is the
only place on Earth where 185 million years of the Earth’s history are
sequentially exposed. Although called "Jurassic", the coast exposes
rocks from the Triassic, Jurassic and Cretaceous periods spanning the
entire Mesozoic era, between 250 million and 65 million years ago.
At the far west end, the cliffs date to the Middle Triassic period, some
250 million years ago, when what is now England was located in the
center of the vast supercontinent Pangaea. The climate was dry and arid
with desert basins and forests of conifers instead of ferns. The first
dinosaurs evolved during this time and most groups of four legged
animals had emerged by the end of the Triassic, including frogs,
turtles, crocodiles and the first true mammals.
More toward the middle of this coast and geological timespan, the rock
formations represent the early Jurassic period of about 180 million
years ago. By this time the continental plates had started to drift
apart, the sea-level started to rise, and a warm, shallow sea flooded
over what is now Dorset and East Devon. The rich fossil finds around
Lyme Regis attest to the diversity of life found in these seas.
One of these fossils, and the person who discovered it, proved to be
especially important for the modern understanding of life on earth. That
person was Mary Anning and her discovery in 1811 was the first complete
skeleton of an ichthyosaur, a dolphin-like marine dinosaur. She also
discovered the first two plesiosaur skeletons ever found and the first
pterosaur skeleton found outside of Germany. Her discoveries contributed
to fundamental changes in scientific thinking during her lifetime and
became key pieces of evidence for the concept of the extinction of species.
On the eastern end of the coastline are remnants from the Cretaceous
period, 140 million to 65 million years ago. In the early Cretaceous,
much of Britain was again above sea-level and the strata in southern
England were deposited under lake and river conditions. A few million
years later, there was another global rise in sea-level flooding most of
Britain, where marine conditions then prevailed.
It was from these Cretaceous deposits that I collected soil at Lulworth
Cove. Here I was able to sample the Wealdon clay created from river
deposits and the Greensand and Gault clays created by marine deposits.
This was the first soil sample that I gathered for Gary, and
unfortunately I didn't have Phillip take a picture of me. But here are
some photos of the cove and collection sites.
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