As a contrast to ‘heading for the hills’ in the wonderful sunny weather we had earlier this week we took a walk down to the beach . We headed to the Black Isle here on the east coast of northern Scotland. Close to the tip of this peninsula of land (no, it’s not an isle at all) is the village of Cromarty made famous by Hugh Milller, who lived here and who was one of the most important Scottish Geologists of the 19th Century.
Hugh Miller wrote several books based on his ‘geological ramblings’ going into great detail about the geology, sites and finds he made. The beach at Eathie was one of those which he regularly visited as it was of great geological interest to him and is where he famously collected fossils in the 1800s. He created the path down the cliffs for geology students and fossil collectors. This path is part of the ‘Hugh Miller Trail’.
We parked in the small parking area and headed downhill enjoying the shade of the pine trees. (How rare is it to say that in March!). The path is fairly steep, but was dry and no problem at all.
When we emerged at the bottom onto the shore, we headed 100 m south long the beach to the old salmon fishing station bothy. This now houses a few display/interpretation boards about the area.
According to the Scottish Geodiversity Forum
The rocks at Eathie formed during the Kimmeridgian period of the Late Jurassic (between 148 Ma and 142 Ma). They are generally sandstones and black shales with a few limestone beds. Syn-sedimentary sandstone intrusions cross-cut the black shales in places. These are the result of the liquefaction of sand by earthquakes, followed by their intrusion into local solidified sediments. It is most likely that the earthquakes resulted from movement along the Great Glen Fault which forms the sea cliff to the back of the shore at Eathie.
I collected samples of some of these rocks (as part of a Geocaching ‘Earthcache’ challenge) and arranged them on the windowsill of the old bothy to photograph.
Ammonites and fish fossils are to be found in these deposits that are exposed on the foreshore. The site is designated SSSI (Special Site of Scientific Interest) – it is illegal to use a hammer to break off or break open fixed rock deposits here. Some fossils can be found loosely lying in various locations, however Eathie is probably the most collected site for Jurassic fossils in the whole of Scotland. I wandered around the beach immediately in front of the old bothy and found a few small Ammonites in the flat pieces of very soft black Oil Shale deposits.
We weren’t here just to look for fossils, but to enjoy all the delights of the rocky coast. We headed north along the beach as we wished to see if it was possible to get along as far as McFarquhars’s Cave which we had visited on a previous visit. We’d checked the time tables and we were here just after high tide. We managed about 3 km along the beach before the boulders became too large to scramble over and ahead the sea was still hard up against the cliffs. These cliffs were the home to dozens of shags, some of which we’d seen sitting on the rocks in the sun.
I really like exploring the inter-tidal zone; I’m fascinated by living organisms that are perfectly adapted to cope with spending half their life submerged in the salty seawater and half exposed to the air. The afternoon’s stroll revealed lots of interest.
Common Limpets – Patella vulgata
Adult limpets usually return to the same area of rock after feeding. They form a small depression, known as a scar, by rubbing against the rock. This scar ensures a tighter fit for the shell, helping the limpet avoid desiccation.
Spiral wrack – Fucus spiralis
Spiral wrack survives the long periods it is out of water by the fronds curling as it dries so that there is less surface area. The fronds produce slimy mucus to keep them moist.
A holdfast is the root-like structure at the base of an algae (seaweed) that fastens the algae to a hard substrate. Holdfasts are different from roots in that they do not absorb moisture.
Rocks – beautiful rocks
We hope that these sailors made their way back to the harbour safely!