do you live on a lava flow?
DESCRIPTION
ÂTRANSCRIPT
Monifieth
Broughty Ferry
Claypotts
Douglas
Whitfield
FintryMill o’MainsTrottick
Bridgefoot
LonghaughRoad
Balmossie
Arbroath Road
Mains Castle
Caird Park Viaduct
Camperdown
Invergowrie
Piperdam
Lundie
Lundie Loch
Bridgefoot
DUNDEE
Extrusive Volcanic Bedrock
Intrusive Igneous Bedrock
Dundee Flagstone
Not Mapped
Fault Lines
1
2
3 45
1 Lundie Craigs (Lava)The source of the Dighty is Lundie loch and the burnappears as a spring on the North Lundie Road. Lava flowsform the escarpment of Lundie Craigs above the loch andthe rock is exposed in a small cutting behind Lundie villagehall (NO289367).
2 TrottickThis was formerly an area of extensive bleachfields. Justupstream from the road bridge at NO400341, red siltstoneof the Dundee Flagstone can be seen in the riverbed. In thesouth bank of the burn is a coarse-grained dolerite sill.
3 Mains CastleIn the Gelly Burn below Mains Castle, a dolerite sill forms asmall waterfall and cliffs on the north bank. The walls ofMains Castle (NO411330) are built of many different rocktypes, including boulders carried down from the Highlandsby Ice Age glaciers.
4 Longhaugh QuarryActive in the first half of the 20th century, this quarry at NO429330 has now been closed and landscaped. A dolerite sill was quarried for roadstone.
5 Balmossie (Lava)The Dighty Burn flows through lava all the way from theArbroath Road bridge to the Firth of Tay. Lava can be seenin river cliffs about NO477326.
Lundie Loch
The Dighty Burn at Strathmartine The Dighty Burn at Bridgefoot Looking up to the Volcanic Sill at Lundie CraigsThis map shows the appropriate position of each site. Ordnance surveydata @ crown copyright and datazone right 2011.
Rock left by past Volcanic activity at Lundie CraigsMains Castle Wall showing the variety
of local rock used to construct it.
DO YOU LIVE ON A LAVA FLOW?The Geology of the Dighty Burn
from Lundie Craigs to the sea at Monifieth
Remember the Geology Code•Keep collecting to a minimum•Try not to hammer: if so wear googles - better with fragments•Seek permission to go onto private land•Do not dig out any site - leave it as it was found•Do not leave rock fragments as litter on roads or fields•Do not disfigure rocks•Leave things so people after you can enjoy them•Follow the Scottish Outdoor Access Code•Wear hard hats for unstable rock above you•Use common sense
DightyConnectDightyConnect, a confluence of people and nature,DightyConnect is a volunteering project enabling local people living along the banks of the Dighty to be involved in environmental and cultural projects connected to the Burn.
For more information please contact:Ann on 01382 436932 or [email protected] or Jane on [email protected]
Computer-generated map of the Dundee area showing the land streamlinedby ice flowing west to east. The dark blue line is the Dighty Burn.
Photography kindly supplied by Aaren Chacko, David ShandMichael Hambrey and Carol Pudsey.
Devonian scene image copyright Richard Bizley.
We would like to thank Dr Carole Pudsey for providing the technical information and Leslie Reeves for the generation of the idea for the leaflet.
DevonianD I G H T Y
Igneous Glaciers History Tectonics You
About 400 million years ago Scotlandwas part of a large continent located inthe tropical zone south of the Equator.To the northeast were high mountainsand a huge river flowed southwestthrough the Dundee area. Sand, siltand mud from the river and nearbylakes are now sandstone and flagstone,some with fossil plants and fish.
Lava was erupting from volcanoes andfissures, spreading out across the landsurface. Molten rock (magma) coolsquickly at the surface and forms crystalstoo small to see. The rock looks greyand even-grained, sometimes withbubbles if there was gas in the magma.Some magma didn’t make it to the surface but was squeezed betweenolder layers of rock to form a sill. A sillcools more slowly and the crystals arebig enough to see.
Starting about 2.5 million years ago.Scotland was covered again and againby ice sheets. The ice eroded themountains of the Highlands and carvedout deep valleys. In the lowlands theland was smoothed and streamlined.When the ice last melted 20,000 yearsago it left thick layers of till - a mixtureof stones, sand and mud.
This is a general name to cover allearth movements, from tectonic platesmoving round the Earth to faults youcan see in a rock outcrop. The Dundeeflagstones and lavas, along with thesills, were gently folded and tilted, then broken by faults.
You can walk along the Dighty Burn, orlook down to its valley from the braesabove, and see these features yourself.
400 million Devonian lavas and
years sandstones.
350-300 Earth movements.
million years Intrusion of sills
300-2.5 No geological record in
million years the Dundee area.
2.5 million - Ice sheets.
15,000 years Eroded and deposited till.
15,000 years Ice melted, sand and gravel
- present left behind.
Sea level rose and fell.CU-COC-813701
This document has been printed on environmentally responsible paper in accordancewith the rules of the ForestStewardship Council.
A Devonian landscape scene A view from the Lundie Craigs