Final Geology Audit and Assessment Report
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Landscape Monitoring Project - Geology Audit and Assessment Final Report, January 2019 Arnside & Silverdale AONB Landscape Monitoring Project - Geology Audit and Assessment – Final Report Bibliographic Reference: Thompson, A and Poole, J.S. 2019 (a): Arnside & Silverdale AONB Landscape Monitoring Project - Geology Audit and Assessment: Final Report. Cuesta Consulting Limited, East Lambrook. QA Reference: C/ASAONB/020. Issued 18th January 2019 Photographic Acknowledgements: Except where otherwise stated, all All photographs used in this report were taken by the Authors and are used with their permission. In accordance with clause 2.15 of the contract dated 7th March 2018 between the Arnside and Silverdale AONB Partnership and Cuesta Consulting Ltd, except where otherwise stated, those photographs are the copyright of the Arnside and Silverdale AONB Partnership. Arnside & Silverdale AONB Landscape Monitoring Project - Geology Audit and Assessment – Final Report CONTENTS 1. Introduction ........................................................................................... 4 Geodiversity ...................................................................................................................... 5 The Purpose of this Study ................................................................................................. 6 Structure of the Report ..................................................................................................... 7 Map 1 – Geodiversity of the AONB .......................................................................................................... 8 Map 2 – Details of Local Geological Sites and Limestone Pavement Orders ........................................... 9 Map 3 – European & National Designations ......................................................................................... 10 2. The Geological ‘Story’ of the AONB ...................................................... 11 Geo-Jargon - A few essential terms explained ................................................................ 12 The Geological Timescale ................................................................................................ 13 Before the Rocks were Made .......................................................................................... 14 Shallow Seas and Advancing Deltas – the Carboniferous Period ................................... 15 The Carboniferous Limestone Sequence ............................................................................................... 16 Map 4 – Bedrock Geology of the AONB ................................................................................................. 22 Cracking the Crust – the Variscan Orogeny .................................................................... 23 Map 5 – the Silverdale Disturbance ....................................................................................................... 25 The Deserts Return – the Permian and Triassic Periods ................................................. 27 Sunk without Trace – the Jurassic and Cretaceous Periods ............................................ 28 Dissolving Limestone and Further Collisions – the Tertiary Period ................................ 28 Karstic Features of the Limestone Pavements: Clints, Grikes, Runnels & Kamenitzas ....................... 29 Larger-scale Karst: Pavements, Cave Systems, Dolines and Poljes ..................................................... 30 Climate Change and Landscape Response – the Quaternary Period. ............................. 31 Map 6 – Superficial Geology within the AONB ...................................................................................... 32 Hawes Water: A Natural Archive of Quaternary Climate Change ...................................................... 38 Map 7 – Soilscapes within the AONB ..................................................................................................... 42 Map 8 – Priority Habitats within the AONB ........................................................................................... 44 The Present-Day Landscape and Seascape ..................................................................... 53 Map 9 – Landscape Character within and around the AONB ................................................................ 54 3. The Geological Framework ................................................................... 55 Introduction .................................................................................................................... 55 Geological Structure: ....................................................................................................... 56 Martin Limestone Formation and Red Hill Limestone Formation .................................. 60 Dalton Formation ............................................................................................................ 61 Park Limestone Formation .............................................................................................. 66 Urswick Limestone Formation including the Woodbine Shale ....................................... 71 Cuesta Consulting Limited 2 Date: January 2019 QA Reference: C/ASAONB/020 Status: FINAL Arnside & Silverdale AONB Landscape Monitoring Project - Geology Audit and Assessment – Final Report Alston Formation ............................................................................................................. 82 Bowland Shale Formation, Pendle Grit and Millstone Grit ............................................. 82 Triassic Mineralisation .................................................................................................... 83 Glacial Till ........................................................................................................................ 86 Erratics ............................................................................................................................. 89 Glaciofluvial Deposits ...................................................................................................... 92 Talus (Scree) .................................................................................................................... 94 Loess ................................................................................................................................ 96 Lacustrine Deposits ......................................................................................................... 98 Raised Marine Deposits ................................................................................................ 101 Peat ............................................................................................................................... 103 Alluvium and River Terrace Deposits ............................................................................ 106 Saltmarsh Deposits and Shingle Beaches ...................................................................... 107 Intertidal Flat Deposits .................................................................................................. 110 Anthropocene - Slag Deposits ....................................................................................... 112 Summary - Geological Controls on the Natural Environment and Landscape ............. 114 4. Ecosystem Services ............................................................................ 119 The Ecosystems Approach ............................................................................................ 119 Natural Capital and Ecosystem Services ....................................................................... 119 Geological Ecosystem Services within the AONB ......................................................... 120 Beneficiaries of the AONB’s Ecosystem Services .......................................................... 123 5. Guidelines for Conserving and Managing Geodiversity ....................... 129 Theme 1: Increase Understanding of the AONB’s Geodiversity ................................... 129 Theme 2: Influence Planning Policy, Legislation and Development Design ................. 131 Theme 3: Gather and Maintain Information on the AONB’s Geodiversity .................. 132 Theme 4: Conserve and Manage the AONB’s Geodiversity ......................................... 133 Theme 5: Promote and Care for the AONB’s Geodiversity........................................... 135 Theme 6: Sustain Geodiversity Activities within the AONB .......................................... 137 6. Further Recommendations and Opportunities ................................... 142 Key Indicators for Monitoring Future Landscape Change ............................................ 142 Opportunities for Supporting Landscape Resilience ..................................................... 144 Recommendations for further research ....................................................................... 147 References and sources of further information ........................................... 148 Acknowledgements ..................................................................................... 154 APPENDIX A: Geodiversity Field Audit Notes (see separate document) Cuesta Consulting Limited 3 Date: January 2019 QA Reference: C/ASAONB/020 Status: FINAL Arnside & Silverdale AONB Landscape Monitoring Project - Geology Audit and Assessment – Final Report 1. Introduction The Arnside and Silverdale Area of Outstanding Natural Beauty (AONB) is an intricate, close-knit landscape that has been shaped, primarily,