THE FYLDE : GEOLOGY AND PHYSICAL FEATURES 19 



Pilling and Cockerham mosses and the coast. Much of the valley of the Wyre 

 and its tributary streams is river alluvium. An especially wide tract occurs 

 just east of St. Michaels. 



Estuarine alluvium occupies a large area on the north bank of the Ribble, 

 east of Freckleton, and forms the area known as Freckleton Marsh. This is 

 now embanked and drained, and is crossed by the main road from Preston to 

 Blackpool via Lytham St. Annes. Outside the embankments there are 

 extensive salt-marshes and mud-flats, and on the south bank of the river much 

 land has been reclaimed by first encouraging the marshes to increase their 

 extent by planting ' saltings,' consisting of sods of marsh grass laid about two 

 yards apart on the sand or mud. These sods spread and join up with one 

 another in a very few years. They are covered by the sea at every full tide, and 

 during the slack the mud, which has been brought down by the Ribble, and 

 which is in suspension in the water, is deposited and is held by the grass during 

 the subsequent ebb. Thus the level of the marsh is raised by the deposition of 

 an extremely thin, leaf-like layer of alluvium at each tide. When the area is 

 raised sufficiently, it is embanked, and fresh saltings are often planted on the 

 seaward side of the new coastline. 



Coastline. Eastwards of the mouth of the river Wyre, Pilling and Cockerham 

 salt marshes border the beach, and are partly covered during each full tide. 

 Since the coast here faces north, and the dominant wind and most gales are from 

 the west, it does not face the full strength of the largest waves. 



From Fleetwood the coast continues to face northwards for over a mile and 

 a half from the mouth of the Wyre. Rossall Point is then reached, and from 

 here to South Shore, Blackpool, the coast faces due west. Observations made 

 at the numerous groynes between Fleetwood and Blackpool show that there 

 is a fairly powerful longshore drifting of beach material northwards. North 

 Wharf, a bank which extends northward of the Fleetwood to Rossall Point 

 coastline for a distance of two miles, may probably be explained by this 

 northerly drift's failing to round Rossall Point, and continuing northward until 

 checked by the tidal stream of the river Lune. 



From Fleetwood to near Cleveleys there is a very large amount of shingle 

 on the foreshore, and on the bend of Rossall Point there are several examples 

 of shingle ridges, continuing northwards although the land falls away eastwards 

 behind them. 



From Cleveleys to North Shore the shingle gradually decreases in amount, 

 until at North Shore there is only sufficient to form a triangular patch on the 

 southward side of each groyne. From North Shore to South Shore, Blackpool, 

 there is no shingle, the beach consisting entirely of quartz sand. 



Sea walls protect the whole 12 miles of coast from Fleetwood to South 

 Shore, Blackpool. A low alluvial coast stretches from Fleetwood to just south 

 of Cleveleys, where peat outcrops on the foreshore. Then cliffs of Boulder 

 Clay gradually rise to a maximim of 100 feet at North Shore, Blackpool, 

 decreasing again and near the Tower giving place (although hidden by the 

 sea wall) to low cliffs of blown sand, which forms the coastline to Freckleton 

 Marsh beyond Lytham. 



From the end of the Promenade at South Shore to Freckleton Marsh, 

 there is a variable band of shingle on the backshore, the foreshore consisting 



