Please be aware as this is a Local Nature Reserve and RIGS (Regional Important Geological Site) please ensure that all local wildlife, flora and fauna are respected and keep to the designated footpaths – there is no need to deviate from the paths to claim this cache.
Helsby Quarry is a safe, welcoming and well maintained park on the site of an old sandstone quarry dating back to the 19th Century. More recently, it was designated as a Local Nature Reserve in 2001 for wildlife and people and is also a RIGS (Regional Important Geological Site) for its sandstone cliff faces formed in the Triassic period.
The geology of the site is one of its main features and it is designated a Regionally Important Geological site. The site is part of the Helsby Sandstone Formation which is a result of activity about 250 million years ago. The sandstone formations that make up the quarry wall and man-made tunnel within the site were formed during the Triassic Period from river deposits and sand dunes.
The formation of sandstone involves two principal stages. First, a layer or layers of sand accumulates as the result of sedimentation, either from water (as in a stream, lake, or sea) or from air (as in a desert). Typically, sedimentation occurs by the sand settling out from suspension; i.e., ceasing to be rolled or bounced along the bottom of a body of water or ground surface (e.g., in a desert). Finally, once it has accumulated, the sand becomes sandstone when it is compacted by pressure of overlying deposits and cemented by the precipitation of minerals within the pore spaces between sand grains.
The Chirotherium
During Triassic times some 200 million years ago, a large carnivorous reptile known as the Chirotherium existed in our area and its fossil footprints are occasionally found during quarrying work. The name comes from its resemblance to the human hand. Tracks of this early reptile, an early ancestor of the later dinosaurs, were first discovered in Germany in 1835 then in Cheshire in 1839 and since in many other parts of Europe and in North America.
Although many Chirotherium footprints have been found no bones or other fossil remains have ever been discovered. From the differences between the tracks found, over 30 species of these animals have been named. Attempts have been made to reconstruct the appearance of the reptile from its tracks. In Switzerland in 1965 a fossil of a Triassic reptile which would have left similar tracks has confirmed the general accuracy of the reconstruction. The animal would have normally walked on four legs, carrying its tail off the ground, but examples of tracks showing hind footprints and tail marks suggest that it could walk on its hind legs. All the toes end in claws, and in some impressions a scaly texture can be seen. The animal was carnivorous and grew to a length of 8 to 10 feet.
How to claim this cache
The co-ordinates provided are for the recommended parking area (with sufficient space for approximately 8-10 cars) off Alvanley Road. From here follow the main trail though the woods to the first reference point. The path is fairly level at this stage, with only a slight decline down into the quarry (including some very small, flat steps) and you may take dogs with you on the walk. From this point follow the footpath along until you reach a fork in the paths. Take the right path (please be careful as the footpath does have some fairly steep steps) and take a left down towards the tunnel.
1) Visit the first reference point (N53 16.075 W002 45.957) where you will find the quarry wall. At the far right of the wall there is an ‘uncaged’ section of wall (there is no need to deviate from the footpath to find this):
a) Please describe the appearance of the sandstone beds (in comparison with the ‘caged’ section of the wall).
b) Estimate the depth of the darker layers.
2) Visit the second reference point and take a photo of you or your GPS in front of the tunnel entrance - N53 16.093 W002 46.027 (optional).
3) Visit the third reference point at the exit of the tunnel (N53 16.103 W002 46.064). On the left hand side (after exiting the tunnel) you will see the clearly defined sandstone beds that form the wall of the tunnel. Estimate the angle at which the beds lie when compared with the floor of the tunnel.
Please e-mail me the answers through my profile and do NOT include them in your log (even if encrypted). Also, do not post any photographs of the information boards as that would also give away the answers to some of the questions.