Cainozoic geology and landscape evolution of north-east Scotland. Memoir of the British Geological Survey, sheets 66E, 67, 76E, 77, 86E, 87W, 87E, 95, 96W, 96E and 97 (Scotland)

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The Cainozoic geology and landscape evolution of north-east Scotland memoir has been converted to a series of articles for this wiki. The book is available for purchase at the BGS Online Shop Its full reference is:

Merritt, J W, Auton, C A, Connell, E R, Hall, A M, and Peacock, J D. 2003. Cainozoic geology and landscape evolution of north-east Scotland. Memoir of the British Geological Survey, sheets 66E, 67, 76E, 77, 86E, 87W, 87E, 95, 96W, 96E and 97 (Scotland).

Contributors: J F Aitken, D F Ball, D Gould, J D Hansom, R Holmes, R M W Musson and M A Paul.

Contents

One Introduction

Solid geology
Dalradian
Caledonian orogeny and magmatism
Ordovician, Devonian and Carboniferous
Mesozoic
Summary of Cainozoic geological history
Palaeogene and Neogene (formerly the Tertiary)
Quaternary (Pleistocene and Holocene)
Classification of deposits
Lithostratigraphy
Chronostratigraphy
Geochronometry
Radiocarbon dating
Amino-acid dating
Luminescence dating

Two Applied geology

Bulk mineral resources
Sand and gravel
Brick clay
Peat
Hydrogeology
Alluvial deposits
Glaciofluvial deposits
Blown sand
Till
Bedrock
Groundwater quality
Groundwater exploitation
Planning considerations and conservation issues
Ground stability and foundation conditions
Engineering properties of glacigenic sediments
Deeply weathered bedrock, periglacial and postglacial deposits
Made, landscaped and worked ground, and landfill
Landslips
Coastline stability
Seismicity and seismic hazard
Land use
Soils
Agriculture and forestry
Shallow geophysics and remote sensing
Satellite imagery

Three Landscape evolution

Palaeozoic and Mesozoic
Inherited Devonian surfaces
Marine inundation during the Mesozoic
Palaeogene and Neogene
Tectonic activity
Climate and weathering
Landscape evolution
Cumulative glacial erosion during the Quaternary

Four Palaeogene and Neogene deposits, weathering and soil development

Deposits
Buchan Gravels Formation
Deep weathering and soil development
Distribution
Characteristics of the weathering profiles
Weathering patterns
Saprolite characteristics
Weathering types and age

Five Quaternary Period

Global record of climate change
Deep ocean record
Greenland ice core record
Offshore stratigraphical record
Early Quaternary
Middle Quaternary
Late Quaternary
Onshore stratigraphical record
Early Quaternary
Middle Quaternary
Late Quaternary
Previous models of glaciation
The work of Jamieson
The work of Bremner and Read
Work post the Second World War
Work in the late1960’s to the early 1980’s
Work in the last two decades of the Twentieth Century
Present model of glaciation
Early stage of the Main Late Devensian glaciation (c. 28 to c.22 ka BP)
Partial glacial retreat during a mid-Late Devensian interstadial (c.22-18 ka BP).
Later stages of the Main Late Devensian glaciation (18 ka-13 ka BP)
Some conclusions from 150 years of research into the glaciation of NE Scotland

Six Quaternary deposits

Glacial deposits
Till
Hummocky glacial deposits
Glaciofluvial and glaciolacustrine deposits
Glaciofluvial deposits by geological sheet
Glaciolacustrine deposits by geological sheet
Periglacial deposits
Alluvial and aeolian deposits
Organic deposits
Raised marine deposits
Present-day marine deposits

Seven Geomorphological features

Features of glacial erosion
Glacial striae, roches mountonnées and glaciated rockknolls
Drumlins, drumlinoid ridges and large-scale gouges
Ice-scoured depressions
Features of glaciofluvial erosion
Glacial meltwater channels
Subglacial, ice-directed channels
Ice-marginal and submarginal channel systems
Extensive ice-marginal and interlobate channel systems
Proglacial spillways
Buried valleys
Features of glacial or glaciofluvial deposition
Eskers, kames and moraines
Erratics
Glacial rafts
Periglacial phenomena and features of mass wastage
Periglacial features
Earth-pillars
Features of marine erosion
Late Devensian raised beaches
Flandrian raised beaches
Raised wave-cut platforms and associated features
Submerged wave-cut platforms
‘Pre-glacial’ raised beaches

Eight Quaternary lithostratigraphy and correlation

Introduction
Banffshire Coast Drift Group
Till
Sands and gravels
Glaciolacustrine deposits
Glaciomarine deposits
Mearns Drift Group
Relationships between Mearns and East Grampian drift groups
Logie-Buchan Drift Group
Relationships between Logie-Buchan and East Grampian drift groups
Relationships between Logie-Buchan and Banffshire Coast drift groups
Relationships between the Logie-Buchan and Mearns drift groups and the Benholm Clay Formation
East Grampian Drift Group
Tills
Sands and gravels
Glaciolacustrine deposits
Central Grampian Drift Group
Till
Other deposits

Information sources

References

Index

Appendices

Appendix 1 Important localities

1 Teindland, near Elgin
2 Boyne Limestone Quarry
3 Castle Hill, Gardenstown
4 King Edward
5 Crossbrae Farm, Turriff
6 Howe of Byth Quarry
7 Kirkhill and Leys quarries
8 Oldmill Quarry
9 Philorth valley, Fraserburgh
10 Ugie valley
11 St Fergus (Annachie)
12 Sandford Bay
13 Windyhills
14 Moss of Cruden
15 Ellon (Bellscamphie)
16 Kippet Hills, Slains
17 Errollston Clay Pit, Cruden Bay
18 Mill of Dyce
19 Strabathie
20 Nether Daugh, Kintore
21 Rothens, Monymusk
22 Nigg Bay, Aberdeen
23 Loch of Park
24 Balnakettle
25 Knockhill Wood, Glenbervie
26 Burn of Benholm

Appendix 2 Bulk mineral resources

History of sand and gravel resource appraisal, Cainozoic of north-east Scotland
Aggregate testing results, Cainozoic of north-east Scotland
Sand and gravel resources, Sheet 95 Elgin, Cainozoic of north-east Scotland
Sand and gravel resources, Sheet 96W Portsoy, Cainozoic of north-east Scotland
Sand and gravel resources, Sheet 96E Banff, Cainozoic of north-east Scotland
Sand and gravel resources, Sheet 97 Fraserburgh, Cainozoic of north-east Scotland
Sand and gravel resources, Sheet 86E Turriff, Cainozoic of north-east Scotland
Sand and gravel resources, Sheet 87W Ellon, Cainozoic of north-east Scotland
Sand and gravel resources, Sheet 87E Peterhead, Cainozoic of north-east Scotland
Sand and gravel resources, Sheet 76E Inverurie, Cainozoic of north-east Scotland
Sand and gravel resources, Sheet 77 Aberdeen, Cainozoic of north-east Scotland
Sand and gravel resources, Sheet 66E Banchory, Cainozoic of north-east Scotland
Sand and gravel resources, Sheet 67 Stonehaven, Cainozoic of north-east Scotland

Appendix 3 Results of shallow geophysical surveys

Conductivity
Resistivity
Ground probing radar

Cainozoic geology and landscape evolution of north-east Scotland

This memoir provides a synthesis of the Cainozoic (Palaeogene, Neogene and Quaternary) geology of a large part of the coastal area of north-east Scotland stretching from Elgin to Inverbervie and portrayed on the ‘Drift’ editions of eleven 1:50 000 geological sheets. The nature, origin and distribution of the superficial deposits are described, together with their use as a resource and as foundation materials. It draws on the results of surveys undertaken over the past 30 years or so, and acts as a guide to the large archive of more detailed information held by the British Geological Survey. It also incorporates and synthesises much information stemming from university research, and is coauthored by leading research workers out with BGS.

The complexity and variety of the Quaternary succession in the district is unrivalled in Scotland particularly for the record it contains of cold stages represented by periglacial deposits and the presence of sediments with a biological or pedological record of interstadial and interglacial climates. The widespread preservation of ancient peneplanation surfaces associated with deeply weathered rock and enigmatic flint and quartzite gravels is unique in north-west Europe. These features, together with a significant offshore stratigraphical record, provide unique information illustrating the effects of Pleistocene glaciation and Cainozoic landscape evolution. The area offers a broad range of future research and teaching opportunities that can draw on the definitive account presented here.

Much of north-east Scotland was peripheral to the main centres of ice accumulation in the west of Scotland during the Pleistocene glaciations resulting in minimal glacial erosion. It repeatedly witnessed the interaction between sluggish, cold-based ice flowing from an inland source and relatively fast, low-gradient ice streams flowing over deformable sediments offshore. A partial record of at least three major glaciations and intervening ice-free periods is preserved. During the last (Main Late Devensian) glaciation, the district was crossed by several distinct ice streams that partially retreated and then re-advanced on more than one occasion. This resulted in the deposition of complex sequences of glacial, glaciofluvial and glaciolacustrine deposits of varied provenance together with of a range of glacitectonic phenomena including numerous glacial rafts derived from the floor of the Moray Firth. Large rafts of Jurassic clay are particularly common. The pattern of deglaciation is also recorded in an extensive network of meltwater channels, and in the raised beach, estuarine and glaciomarine deposits, formed as a result of the considerable glacio-isostatic depression of the ground. Following a period of low sea level in the early Holocene, the Main Postglacial Transgression resulted in marine inundation of the river estuaries and the deposition of estuarine silts, sands and clays, locally over peat.

Preface

Pressures on present-day environments are continually increasing. In areas of population and industrial growth such as the coastal zone between Stonehaven and Peterhead, the need for a thorough understanding of the local natural resources, hazards and ground conditions is paramount. A major aspect of this need is a comprehensive knowledge and understanding of the geological, geomorphological and environmental changes that have occurred over the past few million years, and which were responsible for the present distribution of drift deposits and landforms. To this end the British Geological Survey is directing research towards the Quaternary period, particularly concentrating on major centres of population, as well as surveying neighbouring rural and wilderness areas where relatively little geological information is currently available.

This memoir is a synthesis of the Cainozoic (Palaeogene, Neogene and Quaternary) deposits over a wide area of north-east Scotland and represents a departure from the previous survey styles. It focusses on the nature, origin and distribution of the drift deposits, their use as a resource and as foundation materials. As such it represents part of the large geoscience database that BGS holds for the UK that is available to provide solutions to geological problems as well as underpinning the scientific understanding of glacial processes, landforms and deposits. It describes areas that have been resurveyed by BGS over the last few decades in the coastal areas of north-east Scotland and portrayed on the Drift or Solid-and-Drift editions of eleven 1:50 000 geological sheets. Much of the mapping was undertaken as commissioned research specifically for sand and gravel resource appraisal or as part of environmental geology portfolios. Although the drift deposits on some of the sheets have been documented elsewhere in BGS publications, most have not been described systematically.

Several classic concepts of the British Quaternary have been formulated in north-east Scotland over the past 150 years, including the pioneering research work of Thomas Jamieson and James Croll during the 19th century. Croll first suggested that ice ages were caused by changes in the amount of solar irradiance received at the poles as a result of changes in shape, tilt and wobble of the Earth’s orbit around the Sun. This memoir summarises and builds on a wealth of research work published in the literature, particularly in publications of the Quaternary Research Association and Scottish Natural Heritage. It includes an analysis of how the landscape of north-east Scotland evolved throughout the Cainozoic era and it summarises our present understanding of the Quaternary events that have affected the district. Several research workers outwith the British Geological Survey have contributed to this memoir, in particular A M Hall and E R Connell, testifying to the co-operation of university academics with BGS’s core programme. This collaboration together with the combination of publically funded and commissioned research furthers understanding of British geology and enhances the national database of earth science information available to the public.

David A Falvey, PhD

Director

British Geological Survey Kingsley Dunham Centre Keyworth Nottingham NG12 5GG