a chance to pretend you're on the set of Lord of the Rings at this point.
As we continue to wind up towards the Tor we pass both Fern and Roman Caves.
both has been restricted at the moment on health and safety grounds. Though
they're called caves, this isn't strictly true. They are actually mine
on the surface of the limestone
prime examples of open mineral veins. Spanning from three to 10 feet in
width. The mineral has been totally extracted from these veins and today
we're left with an open chasm to the surface.
Stop at the
caves and have a good look around making sure you don't pass the boundaries.
It's an important
spot here as we can clearly see striations - scratches made on the rock
surface, generally parallel, inscribed by a geologic agent, i.e., glaciers,
streams, or faulting on the limestone.
here are perhaps 300 million years old and a result of earth movements.
The two pieces of rock have slid horizontally against one another and
left scratch marks on the surface.
Local Geology expert Robin Jeffcoats tells us more about Matlock's
geological gems and when the Romans lived here.
as Robin talks the talk as we walk the walk
to listen to
We took a walk through time on Otober
16th. Take a look at the pictures.
you've heard of the San Andreas fault in California USA? Well, this is
on the rocks' surfaces here, they can be quite misleading, some of them
are pale and look similar to crystals whilst others have a rusty tone
to them leading you to believe you're seeing iron deposits or fluorspar.
In the caves
you may notice that the limestone is tilting quite steeply revealing the
bedding planes - layers the limestone was actually deposited in. These
layers may have been originally horizontal on the seabed but now the strata
has been tilted by earth movement.
and Matlock would have certainly been underwater around 330 million years
ago - during the Carboniferous period.
have been an era of great development for Matlock's limestone but the
area would have been totally unrecognisable.
Bahamas and you'd have a better idea how the area would look.
If we'd been
around at that time we'd have been living in a tropical atoll, a lagoon
with beautiful corals and teaming sea life, from the minutest of shell
fish to huge sharks.
been clam like species (brachiopods), sea lilies (crinoids) and other
ancient creatures all co existing in this shallow tropical sea.
the tropical seas became overwhelmed by muds and sands from the north,
big river deltas spread sands and silts across the area this was a precursor
to the coal measures.
and sea life perished and was eventually buried below the silt.
All of the
coal measures and swamps have eroded away from this area and this has
again revealed the limestone along with a few fascinating fossils that
have been left over.
to believe that Derbyshire's limestone was actually formed about 15 degrees
south of the equator. Over the last 300 million or so years they've slowly
travelled to Derbyshire.