School of Geographical & Earth Sciences

Rock around the University will help you to:

• Identify rocks, measure geological structures and locate yourself on a topographic map
• Construct a geological map of the underlying rocks
• Draw geological cross sections through the area
• Establish the 3D geometry of the rock sequence and determine the interaction of geological boundaries with the landscape
• Assess the geological history of the area and evaluate the geological resources present

Teaching Earth Sciences at the University

Rock around the University aims to develop the ability to think and reconstruct geological structures in 3D. These are key skills for all professional Earth scientists, essential for the assessment of subsurface resources, such as hydrocarbons and ore minerals, or the identification of safe sites for waste storage. The facility allows us to introduce rigorous field-based teaching at an early stage in the Earth Science courses and encourages reflective learning in students. Earth Science students locate, analyse and synthesise information in the field to provide effective solutions to problems and use “Rock around the University” as a self-directed learning experience where they build confidence while working independently in a familiar environment. Hence they reinforce their skills before experiencing independent work in remote areas.

For all it is an opportunity to experience Earth Sciences in the field and learn what geology is all about.

All rocks for Rock around the University were donated by local companies mostly from quarries or surface mines, and transported to the University of Glasgow depot in Govan. The teaching resource could not have been constructed without the generosity of these companies. Locally sourced rocks were chosen so that they could be used to tell key chapters in the geological history of Scotland. Individual blocks were selected to clearly demonstrate key characteristics of each rock type.

The limestone and basalt are from Trearne and Loanhead quarries near Beith in the Carboniferous rocks of Ayrshire, operated by William Tracey Ltd and WH Malcolm Ltd respectively. The sandstone blocks were donated by Raeburn Brick and are from a surface coal mine at Edge Farm, near East Kilbride in South Lanarkshire. The granite came from Tom’s Forest Quarry, near Kemnay in Aberdeenshire and was supplied by Bardon Aggregates. The schist was sourced by URS Infrastructure & Environment UK Ltd from spoil from road cuts associated with a recently constructed access road between Garelochhead and Arrochar; BAM Ritchies did the geotechnical work on the road and supplied the blocks.

Loanhead Quarry (WH Malcolm)

       

Tom’s Forest Quarry (Bardon Aggregates)

 

Trearne Quarry (William Tracey)          

 

 Edge Farm surface mine (Raeburn Brick)

 

Blocks near Garelochhead (BAM Ritchies)

Sites on campus were selected to cause minimal environmental disruption and designed to look like natural rock exposures wherever possible. The Estates Committee of the University of Glasgow approved the scheme and once sites were identified and members of Estates and Buildings liased with planners from Glasgow City Council. Staff at Estates and Buildings organised the storage and placement of the blocks, signage and helped throughout the project.

Individual blocks are up to 2.5 m long to ensure that they are stable when dug into position and are big enough to show large groups of students. The biggest blocks were split into more easily manipulated sizes by Masonry Solutions and transported to the University Campus and emplaced by Reigart Contracts using a Hiab and a JCB. Individual blocks were carefully placed to mimic a geological exposure that could be found naturally in the field. By observing rock types and exposure, students will be able to make a geological map and reconstruct a plausible geological history of the area.

Splitting larger blocks in the Govan yard

 

Loading blocks for transport to the campus

Placing blocks near the Kelvin Building

 

Placing blocks next to the Fraser Building

 

Placing blocks behind the Sir Alwyn Williams Building

The contour map below shows the location of the rocks on the University of Glasgow Gilmorehill Campus.

 

Students use this map to mark the locations of each different rock type and then infer the surface trace of the boundaries between each of the rock units (see section on Geological Structure).

Being a geologist is a bit like being a forensic scientist. Geologists interrogate silent witnesses; the rocks, and, from their features, understand how they were formed in time and space. This section provides a brief description of each of the rocks present in Rock around the University to help identify them and thereby determine their distribution on the campus map.

Schist

Layered grey-green folded metamorphic rock formed from original mudstones that were deposited in horizontal layers in deep ocean water about 600 million years ago. These were subsequently buried and heated in the roots of an ancient mountain belt that formed as original horizontal layers were crumpled during the collision between continental plates around 470 million years ago. The schists were then brought back to the surface by the slow erosion of the mountain tops, removing the rocks above.

 

Granite

Pale grey-pink coarse grained igneous rock containing quartz (glassy grey), feldspar (white and pink) and black shiny biotite. This granite formed about 470 million years ago in the roots of an ancient volcano. The large minerals that can be seen with the naked eye, crystallised within a large slowly cooling magma chamber, at depth in the crust.

Granite is used for road aggregate, stone chippings and facing stone.

 

 

Basalt

Dark grey-purple volcanic rock formed during the rapid cooling of a lava flow. The large white feldspar crystals have crystallised at depth in the magma chamber below the volcano and been carried up to the surface as the lava was erupted. The volcano was active about 315 million years ago. Some irregular shaped patches within the basalt contain very large minerals that crystallised at a late stage as hot water moved in fractures and cavities within the solid rock.

Basalts are commonly used for road aggregate.

 

Sandstone

Buff-brown sedimentary rock mostly composed of small rounded grains of quartz sand deposited about 320 million years ago in a coastal delta of a large meandering river. Sedimentary structures, such as small dune-like features, called ripples, that form in the sand on the river bed, may be used to determine both the direction in which the river was flowing and the water depth. Some sandstone blocks contain small fragments of coal that formed from plant material growing in adjacent coastal swamps.

Used for building stone.

 

Limestone

Cream-grey sedimentary rock largely made of the mineral calcite, containing many fossils, the skeletons of dead sea creatures, including crinoids and brachiopods. The limestone was deposited about 325 million years ago in tropical shallow seas during a period of relatively high sea level caused by the melting of ancient ice sheets near the south pole. The weathered surface of limestone typically has a slightly uneven pitted appearance because calcite will slowly dissolve in rainwater.

Used for agricultural lime and cement.

What order did the rocks form in?

Geologists use a simple principle (that of superposition) to determine the relative age of rocks; the rock that is underneath is usually the oldest, as it was deposited first. Based on this principle, you should be able to put the rocks you have identified in order, from the oldest to the youngest (Ages are in millions of years (Ma)). This principle holds for most sedimentary rocks because these are deposited in horizontal sheets or beds. However, igneous rocks that crystallise from melts typically form at great depths where the Earth is hottest and then move upwards towards the surface through older rock layers. They may not breach the surface and so can be found at any depth irrespective of their age.

What is below the surface?

Geologists attempt to work out what rocks are present below the surface by identifying the rocks at the surface, measuring the orientation of the rock layers and working out how those layers would interact with the surface topography. The block diagram below illustrates how small exposure of rock at the surface may be used to infer the structure of those rocks at depth.

 Typically geologists would use a compass to measure the orientation of the layers, noting the alignment of an imaginary horizontal line on the bedding surface (i.e. the strike line) and the angle at which the beds are tilted (i.e. the dip). Typically the sedimentary beds in “Rock around the University” (i.e. the sandstone and limestone) strike in a north-south orientation and dip at about 15o towards the east. This orientation allows geologists to estimate where the sedimentary layers trace around the hills (see examples below)

A horizontal layer of rock will be exposed everywhere at the same elevation and therefore will simply follow the contours, as shown below in yellow.

Oblique aerial photograph of University of Glasgow campus (image from www.rcahms.gov.uk)

A vertical layer will cut across the topography irrespective of the contours.

Oblique aerial photograph of University of Glasgow campus (image from www.rcahms.gov.uk) 

Schists and granites are typical of the ancient rocks of the Scottish Highlands, formed when Scotland was attached to the southern edge of the N. American tectonic plate. Closure of the ocean between this plate and the rest of Europe (including England), a precursor to the present day Atlantic Ocean, caused the continental plates on either side to collide and folded layered rocks into a huge mountain belt that would have been a similar scale to the Himalayas. At this time volcanoes would have punctured the crust and granites would have crystallised in the magma chambers below. Erosion would have progressively destroyed the mountain exposing the rocks that formed at depth.

Limestone, sandstone, coal and basalt are typical rocks of the Midland Valley of Scotland deposited during the Carboniferous period. These form in original horizontal layers in the low-lying ground close to the margin of the continental block. A further collision of this block with the southern continents (Africa, Antarctica, S. America) occurred in Europe and led to the formation of one enormous supercontinent with all the Earth’s major continental plates joined together. The effects of this collision in Scotland tilted the layers and caused fracturing. More recently, between about 200 and 60 million years ago this super-continent slowly split apart forming the Atlantic Ocean, leaving Scotland on the eastern side, attached to Europe.