Editing The Fens (section)

==Formation and geography==
At the end of the most recent [[Last Glacial Period|glacial period]], known in Britain as the [[Devensian]], ten thousand years ago, Britain and [[continental Europe]] were joined by the ridge between [[Friesland]] and [[Norfolk]]. The topography of the bed of the [[North Sea]] indicates that the rivers of the southern part of eastern England flowed into the [[Rhine]], thence through the [[English Channel]]. From the Fens northward along the modern coast, the drainage flowed into the [[northern North Sea basin]]. As the ice melted, the rising sea level drowned the lower lands, leading ultimately to the present coastline.<ref name="John Coles 1994">{{citation | first1 = David | last1 = Hall | first2 = John | last2 = Coles | title = Fenland Survey. An essay in landscape and persistence | series = Archeological Reports | volume = 1 | publisher = Liverpool University Press, Historic England | date = 1994 | isbn = 978-1-85074-477-1}}</ref>

These rising sea levels flooded the previously inland woodland of the Fenland basin; over the next few thousand years both saltwater and freshwater wetlands developed as a result. Silt and [[clay]] soils were deposited by marine floods in the saltwater areas and along the beds of tidal rivers, while organic soils, or peats, developed in the [[freshwater]] marshes. Fenland water levels peaked in the Iron Age; earlier Bronze and Neolithic settlements were covered by peat deposits, and have only recently been found after periods of extensive droughts revealed them.<ref name="John Coles 1994"/> During the Roman period, water levels fell once again. Settlements developed on the new silt soils deposited near the coast. Though water levels rose once again in the early medieval period, by this time artificial banks protected the coastal settlements and the interior from further deposits of marine silts. Peats continued to develop in the freshwater wetlands of the interior fens.<ref name="John Coles 1994"/>

The wetlands of the fens have historically included:
*[[Arroyo (watercourse)|Wash]]es: these are places such as tidal [[mud flat]]s and [[braided river]]s, which are sometimes exposed and at other times covered with water.
*[[Salt marsh]]: this is the higher part of a tidal wash, on which salt-adapted plants grew.
*[[Fen]]: this is a broad expanse of nutrient-rich shallow water in which dead plants do not fully decay, resulting in a flora of emergent plants growing in saturated peat.
*[[moorland|Moor]]: this developed where the peat grew above the reach of the land water which carried the nutrients to the fen. Its development was enabled where the fen was watered directly by rainfall. The slightly acidic rain neutralized the [[hydroxide ion]]s of the peat, making it more suitable for acid-loving plants, notably ''[[Sphagnum]]'' species. This is the same as [[bog]], but the word ''moor'' was applied to this acid peatland occurring on hills. These moors disappeared in the 19th century. Researchers did not think that the Fenland had this kind of peat, until the discovery of archaeological and documentary evidence showing that it did until the early 19th century.
*Waters: these have included:
**[[Creek (tidal)|tidal creeks]], which reached from the sea into the marsh, the Townlands and in some places, the fen. They were named only if big enough to be regarded as havens
**[[Mere (lake)|meres]], or shallow lakes, which were more or less static but aerated by wind action
** many rivers, both natural and (from Roman times on) artificial

Major areas for settlement were:
*''Townlands'', a broad bank of silt (the remains of the huge creek [[levee]]s that developed naturally during the Bronze and Iron Ages), on which the settlers built homes and grew vegetables for households
*''fen islands'': areas of higher land, which were never covered by the growing peat
*''fen edges'': uplands surrounding the fens

In general, of the three principal soil types found in the Fenland today, the mineral-based silt resulted from the energetic marine environment of the creeks, the clay was deposited in tidal mud-flats and salt-marsh, while the peat grew in the fen and bog. The peat produces black soils, which are directly comparable to the American [[Muck (soil)|muck soils]]. A [[roddon]], the dried raised bed of a watercourse, is more suitable for building than the less stable peat.

Since the 19th century, all of the acid peat in the Fens has disappeared. Drying and wastage of peats has greatly reduced the depth of the alkaline peat soils and reduced the overall elevation of large areas of the peat fens. It is also recorded that peat was dug out of the East and West Lincolnshire fens in the 14th century and used to fire the salterns of Wrangle and Friskney. In later centuries it was used locally for winter fuel and its digging controlled by the [[Duchy of Lancaster]].<ref>Aspects of Yellow Belly History, J. Dear & T. Taylor. 1988</ref>

Written records of earthquakes in the Fen area appear as early as 1048. According to ''Historia Ingulfi,'' p.&nbsp;64, (1684)<ref>{{citation |chapter=Ingulfi Croylandendis Historia|title=Rerum Anglicarum Scriptorum Veterum|publisher=Sheldonian Theatre |year=1684–1691|volume=1|editor-last1=Fulman|editor-first1=William|location=Oxford|language = la|pages=|editor-last2=Gale|editor-first2=Thomas}}</ref> this took place in Lincolnshire. In 1117 one affected Holland, Lincs, "endangering and injuring [[Crowland Abbey]]".<ref>''Ibid.'' p.129.</ref>  In 1185 Lincoln was damaged.<ref>Roger of Hoveden (1201) ''Chronica'', p. 359, as cited in ''Fenland Notes and Queries,'' vol.1, p.28.</ref> In 1448 a shock was recorded in south Lincolnshire (''Ingulfi,'' p.&nbsp;526). In 1750 John Moore records a severe shock attended by a rumbling noise in Bourn after midday. This was felt in Lincolnshire, Leicestershire and Northamptonshire. Houses tottered, slates, tiles and some chimneys fell. As it was a Sunday, some people ran out of the churches "in great consternation".<ref>{{Cite book|last=Moore|first=John|title=Collections for a Topographical, Historical, and Descriptive Account of the Hundred of Aveland|publisher=John Moore|year=1809|location=Lincoln|pages=27}}</ref> In 1792 another shock was also felt in Bourne and neighbouring towns.<ref>''Ibid'', p.27.</ref><ref>{{Cite journal|last=Miller|first=S. H.|orig-date=1889|editor-last=Saunders|editor-first=W. H. Bernard|title=21. Earthquakes in the Fenland.|journal=Fenland Notes and Queries|publisher=Geo. C. Caster|publication-place=Peterborough|volume=1|pages=28}}</ref>