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Characteristics of the Region

TOPOGRAPHY

The Region is an area of enormous variety. The plains of Cheshire and Lancashire are bounded by the Welsh hills and the Irish Sea to the West, and the foothills of the Pennines to the East. In the North the Cumbrian mountains provide a massive barrier to any form of communication in that direction.

Several large rivers flow through the Region. The Dee, Mersey, Ribble and Lune discharge into the Irish Sea and the Eden into the Solway Firth at the Scottish Border. Bridging, at suitable crossing places, was the main reason for the development of the ancient cities and towns of Chester, Warrington, Preston, Lancaster and Carlisle, which became the focal points for early transport systems.

The Industrial Revolution had its roots in the Region. This mainly arose from the exploitation of the coalfields of Lancashire and the West coast of Cumberland, and the availability of ample supplies of water resulting in major changes in economic activity within a substantial part of the area. A century or more of growth in textile manufacturing in the valleys of East Lancashire, in other industries such as engineering, in shipbuilding at Barrow, and in the production of chemicals in North Cheshire arising from the huge deposits of salt, led to the expansion of many other towns and cities.

Of major significance, Manchester became a substantial commercial centre particularly for the textile trade, and the focus of a large conurbation. The Port of Liverpool had been recognised for many years as an essential element in the life of the Region and, although road and rail connections between the two cities already existed, the Manchester Ship Canal was constructed at the end of the 19th century. Historically, the industry located around the mouth of the Mersey had been mainly associated with shipping and ship building but, later, the Ship Canal provided access for tankers to North Cheshire and enabled the construction of oil refineries and the manufacture of petrochemicals.

The coal measures of Lancashire did not extend beyond the Calder Valley and,therefore,little heavy industry existed in the northern part of the Region apart from on the West coast of Cumberland. Agriculture, however continued to be of considerable importance not only on the highly productive arable and dairy-farming land of Cheshire, West Lancashire and the river valleys, but also from stock rearing on the hill farms.

At the end of the Second World War, with a population of over 7 million living in a Region which was so complex both in physical, economic and social terms, there was general recognition that an adequate transportation system was of vital importance to its future prosperity. This was of special significance to an area suffering from the decline of mining, shipbuilding and textiles as new industries, such as those associated with aircraft manufacture and electronics, moved in. Their success is, to a large degree, dependent on the provision of improved links, particularly for those located in the less accessible areas, such as West Cumbria.

The growth in tourism has been of major economic benefit, arising from the increase in the number of visitors from outside the Region. The longstanding attraction of places such as the major seaside resort of Blackpool, and the Lake District have, for many years, had a great influence on traffic. It has been estimated that, in addition to the regular influx of day visitors to the National Park, the resident population may be exceeded threefold by those who stay for an extended period.

As in the rest of the Country, the Region's road system, prior to the construction of the motorways, was predominantly the legacy of past centuries. Its development had been largely fortuitous and lacking in strategic purpose. The only exceptions, were the provision of a number of local by-passes and the construction of the East Lancashire Road connecting Liverpool and Manchester, which was opened in 1934 - the only major new road in the Region since the turnpike era!

GEOLOGY

The proposals for the line of a North-South motorway through Cumberland and Westmorland were confined to a corridor lying to the East of the Lake District massif. A description of the geology of those Counties is, therefore limited to that area.

The predominant Boulder Clay which exists in relatively shallow surface deposits and in drumlins has a wide range of moisture content, between 5% and 25%, and a varying silt, sand, gravel and boulder content.

In the Carlisle area there are deposits of sand and silt overlying bunter Sandstone, and alluvium with sand lenses in the valleys of Rivers Eden and Peteril.

North of Penrith, troughs of peat up to 20 feet in depth are found and in the area there is a volcanic intrusion known as the Armathwaite Dyke.

Further south the bed-rocks are closely jointed partially metamorphosed Silurian Siltstones and Mudstones and elsewhere the more recent Carboniferous deposits are encountered with the limestone containing numerous solution cavities.

In Lancashire, there are also Carboniferous rocks such as limestone, Millstone Grit and Coal Measures in the Pennines and in other high ground such as in the Forests of Bowland, Pendle and Rossendale.

The Carboniferous limestone outcrops in the area around Carnforth and, further south at Clitheroe, in the Ribble Valley This relatively massive limestone can be seen in numerous quarries in both areas. Elsewhere, it is overlain by the strongly-bedded shales, sandstones and gritstones of the Millstone Grit series

The Coal Measures, which overlie the millstone grit over a roughly triangular area to the south of the County centred on Wigan, Burnley and Oldham, are further sub-divided into lower, middle and upper, with the quantity and quality of the coal tending to improve at greater depth. The seams occur in repeating sequences of mudstones, shales and sandstones, and old shallow workings have been frequently encountered.

Younger permo-triassic rocks cover the Carboniferous rocks on the low-lying Lancashire Plain, but there is generally a good cover of drift and there are few outcrops to be seen. The Sherwood/Bunter Sandstone and the Keuper Marl are relatively soft rocks, characterised by a red colour, and the underlying coal seams have been worked in some places by deep mining techniques.

The drift deposits are mainly glacial in origin and are thought to be the product of a glaciation between 2000 and 12000 years ago. The most extensive cover the Fylde, south-west Lancashire and the Mersey embayment as far inland as Manchester, and have been derived from Triassic rocks on the bed of the Irish Sea. Very stoney till from the Lake District was deposited in the northern part of the County and some has intermingled with the Irish Sea drift, extending as far south as the Fylde. On the higher ground to the East, the local Pennine drift contains sandstone and shale fragments, sometimes indistinguishable from the metlwater derived head deposition on the steeper slopes.

In many places, there is a tripartite sequence of drift, with a heavily overconsolidated boulder clay overlying the bedrock. The overconsolidation pressure suggests thicknesses of glacial ice of the order of 250 metres. This Lower Boulder Clay is overlain by Middle Sands, glacial deposits of mainly fine to medium sand, with occasional inclusions of silt and clay, followed by Upper Boulder Clay.

The interglacial period responsible for the Middle Sands also produced locally important fluvio-glacial sand and gravel deposits in the vicinity of Carnforth, and to the North of Manchester in the Middleton/Heywood area. Several deep glacial channels have been recorded in the underlying bedrock, some extending well below present sea level. These channels are often associated with, but not always coincident with, today's rivers and are filled with relatively poorly-consolidated sand, clays and silts.

Lancustrine varved clays were deposited in ice-dammed glacial lakes in the Rossendale and Calder valleys. When the ice dams broke, the rapid draw-down of the water level destablised the clay on the steeper slopes and landslips were a frequent occurrence. The slipped masses are often still recognisable from their upper scarp slopes and bulging toes, but are sometimes obscured by later deposits.

Post-glacial deposits include raised-beaches and blown sands resulting from the retreat of the ice and the sea, and also alluvium in river valleys and estuaries.

Peat deposits are of several basic types, extensive and sometimes deep basin peats, such as at Chat Moss, raised mosses on the poorly-drained till plains in the south and south-east of the County, and thin climatic peat on the plateau areas of the Forests of Rossendale, Bowland and Pendle.

In Cheshire, the western half of the County is generally flat and low lying forming a plain which stretches from the River Dee to Congleton, where the ground rises to meet the Peak District and Pennines. The plain is broken bh the Mid-Cheshire ridge, which extends south from Frodsham towards Malpas. The ridge is intermittent and continues north, though less pronounced, into the Wirral peninsula.

The majority of the solid rock on the plain is obscured by thick glacial deposits left after the advance and retreat of the (Irish Sea) ice sheet. Much of the obscured bedrock is of Triassic age with older Carboniferous rocks exposed to the east of the County around Macclesfield. Tectonic movements have folded the rocks into a basinal structure with generally shallow angles of dip.

To the east of the County the Red Rock Fault, extends south past Congleton and north towards Macclesfield and brings the weaker Triassic Bollin Mudstone formation formerly known as Lower Keuper Marl against the more resistant Carboniferous and marks the edge of the lowland plain. The Carboniferous rocks are of the Millstone Grit Group and are present as shales and more resistant sandstones and gritstones. Coal Measures outcrop only in the northeast of the County near Macclesfield.

The bedrock over the majority of the plain belongs to the Mercia Mudstone Group formerly known as Keuper Marl, a weak rock often eroded and weathered by the ice to form the characteristic red brown glacial till deposits which blankets much of the County. More resistant beds within the Triassic sequence are the Tarporley Siltstone formation formerly known as Keuper Waterstones and the Helsby Sandstone Formation formerly known as Keuper Sandstone which forms outcrops mainly on the ridges, around Peckforton, Beeston, and Delamere. These sandstones are of considerable thickness and are locally important aquifers.

The famous salt beds, the Keuper Saliferous beds now known as Northwich and Wilkesley Halite Formations, are present nearer the middle of the County, notably around Tatton, north east of Lymm, Middlewich, Northwich and Winsford. The topography of the salt bearing areas is marked with subsidence features often infilled with water to form flashes or lakes.

The retreat of the ice sheet left extensive sand and gravel deposits over the County as well as deeply cut channels where the melt waters broke through their temporary dams such as the Deva spillway just north of Chester. Some of the more extensive fluvioglacial sand and gravel deposits are located around Chelford, extending from Rudheath to Gawsworth and as far north as Knutsford and south to Sandbach; and from Sandiway south to Little Budworth. Some of the sands are thought to represent multiple glacial advances and were formerly described with the glacial clays as the tripartite sequence formed of the Lower Boulder Clay, Middle Sands and Upper Boulder Clay. These Middle Sands are present around Congleton where they are quarried. Current thinking is that the glacial deposits represent only the final glacial episode with perhaps relics of previous glacial events surviving only in hollows, and that the complexity of the deposits is caused by progressive melt-out, pockets of stagnant ice, ponding of water and complex drainage relationships.

The main rivers draining the County to-day, comprise the Mersey, Dane, Weaver, Gowy and Dee. The rivers are associated with alluvial deposits and often river terraces formed of gravels. The largest of these rivers are the Dee, and the Mersey both set in extensive alluvial flood plains, which have meandering form. The river Dee runs almost north close to the western edge of the County to Chester, before feeding into a straightened channel through the salt marshes and alluvium and ultimately in to the Dee Estuary. Also of importance is the River Gowy, which rises on the mid-Cheshire ridge and drains northwest towards Frodsham Marsh and Ellesmere Port before discharging into the Mersey estuary. Although this is now a relatively small river, it is associated with considerable thicknesses of peat, which lie between Bridge Trafford and Thornton le Moors.

The Region, with its very strong association with the Industrial Revolution has, as would be expected, many areas which have been extensively modified as a consequence, and contains colliery, quarry and chemical waste heaps, as well as household waste disposal sites adjacent to the urban concentrations