Corsiehill Quarry Kinnoull Hill
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Safety & Code of Conduct Location and Access CORSIEHILL Know the Code… Located on the east side of the Tay, Corsiehill Quarry is reached by turning off the A85 near to the Queen’s P Enjoy Scotland’s outdoors – responsibly! Bridge across the Tay. Turn into Manse Road at the QUARRY P Isle of Skye Hotel and then right into Hatton Road KINNOULL HILL Everyone has the right to be on most which leads onto Corsiehill Road. After half a mile land and water providing that they act turn right into the Corsiehill Quarry car park. near Perth responsibly. P Your access rights and responsibilities are explained fully in the Scottish Outdoor Access Code. If you’re in the outdoors or managing Kinnoull Hill lies on the eastern outskirts of the City of Perth. Its wooded slopes the outdoors, the key is to: and tall cliffs overlook the beautiful River C Take responsibility for your own actions. Tay and are a well known landmark on the southern approaches to the city. Respect the interests of other people. C Corsiehill Quarry cuts into a narrow band C Care for the environment. (dyke) of dolerite rock that runs across the northern flank of the hill. The quarry NRead more by visiting www.outdooraccess-scotland.com is now a visitor car park that gives access to the woodland walks on the hill. A copy of the code is available from: Scottish Natural Heritage on 01738 444177 How & when was it formed? …before you go. Contact Details What kind of rock is it made of? The Corsiehill Quarry forms part of the Tayside Geodiversity How old are the rock formations? Kinnoull Hill Site of Special Scientific c/o Perth Museum,George St., Perth, PH1 5LB Interest (SSSI) and is also Perthshire’s first Tel: 01738 632488 What is its history? Local Geodiversity Site. Email: [email protected] In addition to following the Scottish www.taysidebiodiversity.co.uk/geodiversity Find the answers in this leaflet Outdoor Access Code: Visit this Local Geodiversity Site to see x Please do not hammer the rocks the geological features of the quarry and x Please do not remove any material hill, and explore the woodland park. Take without prior permission in the landscape from the viewpoints and see Kinnoull Tower folly. Feature B - Andesite Lava Feature C - Dyke/Lava contact WHAT TO FIND AT Here the Lava is seen in the north wall after the dyke The baked contact between dyke magma material was extracted. Note the uneven pattern of and the lava is exposed on the sliver of dyke cooling cracks. The rock has a purplish appearance rock left in place after quarrying. CORSIEHILL where not weathered. It is fine grained due to Note the regular cracking at right angles to rapid cooling. Look closely at it and see mineral cooling direction , in places forming polygonal crystals glinting in it (plagioclase feldspar, augite, columns, and also the spheroidal weathering of hornblende and biotite mica). QUARRY dyke rock (dolerite). The more massive andesite lava, Feature A - Quarry Entrance with irregular cooling cracks, The entrance cuts through andesite lava at right is seen in the main quarry face angles to the line of the dyke. behind the dyke material. Note the massive appearance of the lava, with The dyke, intruded as liquid coarse layer dipping gently to the north. It magma, cuts across the solid looks ‘slaggy’ in places with vesicles (originally layers of the much earlier gas bubbles in the liquid lava), some filled with andesite lava, like a vertical wall. minerals (chlorite, calcite or quartz). Feature D - Dyke cross-section A cross-section of the dyke is seen across the west end of the quarry below the wooden steps. The dyke is ‘blockier’ than the andesite lava and has more regular cooling cracks. See how some polygonal cooling columns have developed at right angles to the lava at the sides of the quarry. The lava solidified and cooled long before the molten magma of the dyke was injected from below. The dyke is composed of a Plan of Corsiehill Quarry type of rock called quartz dolerite. It is blue/grey in colour on fresh surfaces and Note how some of the blocks are rounded in appearance due to spheroidal weathering has medium grain size due to relatively slow cooling. The weathered rock is iron-stained and On close examination, the crumbly on the outside, usually with a solid core remaining at its centre. The baked contact dyke rock can be seen to be crystalline, composed between dolerite and lava can be clearly of the minerals augite, seen in the southeast corner where a ‘skin’ of quartz and labradorite the dyke material has been left on the quarry (plagioclase feldspar). wall. View South and West from Kinnoull Hill Summit View North and West from Kinnoull Hill What is a Local Geodiversity Site? Natural History A Local Geodiversity Site can be a landscape, landform Kinnoull Hill Woodland Park encompasses the hills of Kinnoull, Corsiehill, or rock feature that has particular value for education & Binn Hill, Deuchny Hill and Barnhill. It is home to mixed woodland - from tourism, academic research, the history of science, or for its open deciduous woods, to the closed canopy of plantation conifers, aesthetic appearance. The sites usually exhibit a diversity of it is a habitat for both red and grey squirrels, roe deer and a wide features, such as geology, natural history, historic interest variety of woodland birds can be seen, including Jay and Green or archaeology. Local Geodiversity groups identify sites, Woodpecker, and in the winter Redwing and Fieldfare. in co-operation with the landowners, and inform the local council of their potential value. As well as being a Local Geodiversity Site, the hill is designated a Site of Special Scientific Interest (SSSI) with areas of Local geodiversity sites were formerly known as Regionally unique vegetation, including remnants of lowland heath and Important Geological & Geomorphological Sites (RIGS). interesting plants such as the Northern Marsh Orchid. The main aims are: C Conservation, and where appropriate, development and interpretation of sites C To publicise sites within the local community for the purposes of education, scientific and general interest. C To increase awareness in the local community of what exists in the landscape where they live or visit, including information on a website. View South and West from Kinnoull Hill Geology of Corsiehill Quarry Some 300 million years ago during a period Evolution of Tay Rift Valley of further igneous activity in the late Kinnoull Hill is formed from a series of Carboniferous period, molten magma was Underwater, about 390 million Years Ago volcanic igneous rocks, mainly from flows forced along cracks and faults in the strata of andesite lava. These had erupted about as a suite of dykes and sills throughout the 410 million years ago (in the Devonian era) Midland Valley of Scotland. onto a landscape that was probably semi- One of these dykes cuts through the layers Jawless Fish arid and desert-like. The lava flows may of the earlier lava flows which form Kinnoull Water Scorpion have been part of either a magnificent Hill. It is mainly this dolerite dyke that has Folding, about 380 million Years Ago range of high volcanic cones or set in a been exploited at Corsiehill Quarry for Strathmore Sidlaw-Ochil Anticline more subdued landscape like modern aggregates and setts. Syncline Iceland. There was little vegetation at Over the following 300 millions years the this time as land plants were only just land has been uplifted and worn down by evolving and starting to colonise damp wind, rain, ice and frost to its present level. niches in the landscape. Thousands of feet of rock have been removed Faulting, about 300 million Years Ago At this time Scotland was located south by erosion to expose the rocks as we see Sidlaw-Ochil Anticline of the equator on the southern fringes of them today. During the last two million the tropics. years glaciers have planed and scraped the TAY RIFT VALLEY Subsequent earth movements, about land surface, leaving the more resistant 380 million years ago, squeezed the hard volcanic rocks standing as prominent local strata into a great arch with its axis high ground. running approximately along the line of History of the Quarry the present River Tay valley. Much later, Old Red Upper Andesite Lava Fault Sandstone around 300 million years ago, the direction Lower Dolerite Dyke Corsiehill Quarry was owned by the Earls Carboniferous{ of movement changed and the earth’s of Kinnoull. It is clearly marked on the crust in this area was stretched. This first Ordnance Survey map of 1806. It was Dyke: This is a wall-like sheet of igneous created faults along the line of the fold rented to various tenants, mainly in the rock formed when molten magma was and the centre part of the arch dropped Taylor family. It is thought that the quarry intruded into a crack or fault in the to form a rift valley between what is now supplied broken stone for road construction. Earth’s crust, cutting across the layering Tayside and north Fife. Because the rock The quarry cut was extended progressively in the country rock. It is usually vertical strata on Kinnoull Hill are on the north- eastwards until it reached a maximum or steeply dipping. west side of the arch, they slant (dip) length by 1932 when further extension was towards the north with a south facing no longer possible owing to the nearby Sill: This is horizontal or gently dipping scarp, whilst the corresponding strata in houses.