The English Lake District

Field Class Replacement Assessment - “Review the formation and evolution of the English Lake District over the last 25,000 years, providing a detailed description of the different phases and processes that have shaped its structure and current day appearance.”

The Lake District is a region of Great Britain famous for and characterised by its scenery. Craggy peaks and boulder-strewn corries contrast with wooded valleys, farmland, conifer plantations, and ribbon lakes. As well as attracting huge numbers of tourists, the scenery of the Lake District has also afforded it National Park status, and since the publication of the first scientific account of its geology in 1820, by local guide Jonathan Otley, its landscape has become one of the most extensively studied in the British Isles. Through the past 25,000 years, there have been many changes in the landscape of the Lake District, most prominently by glaciation, which is responsible for the general shape of much of the district. The arrival of man also brought about many changes, notably to vegetation and land use.

An Overview of Lake District Geology

The rocks visible at the surface of the Lake District can be roughly divided into three main groups which trend south-west to north-east:

• Skiddaw Slates – these are the oldest rocks in the Lake District, dating from the Ordovician period (c.500 Ma). They are thought to have been formed by the deposition of mud and silt on the seabed, in deep, still water.

• Borrowdale Volcanic Series –formed during a subduction event at c.450 Ma, the Borrowdale Volcanic Series consists of volcanic lavas and pyroclastics. The bulk of the district’s higher, craggier peaks are in this region.

• Windermere Group – slates, shales and sandstones from the...

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...sis. Large numbers of pollen grains are produced for reproduction, and dispersed by the wind. The vast majority shrivel up and are lost, but some fall in areas where their distinctive casings can be preserved – peat bogs favour such preservation (Millward & Robinson, 1970). If a core is taken through many layers of peat, the pollen grain casings present across its depth can provide a chronological record of what plants were present across the time period represented by the core.

The early soils in the Lake District are thought to have been far more alkaline than they are today, particularly those formed from the rocks of the Borrowdale Volcanic Series, which displays veins of white calcite (Pearsall & Pennington, 1973). If a fresh surface of Borrowdale Volcanic rock is exposed, it will react with hydrochloric acid, showing that calcium carbonate is present.