Editing Dorking (section)

==Geography==
===Location and topography===
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Dorking is in central Surrey, about {{cvt|21|mi|km|sigfig=2}} south of [[Charing Cross|London]] and {{cvt|10|mi|km|sigfig=2}} east of [[Guildford]]. It is close to the intersection of two valleys – the north-south Mole Gap (where the [[River Mole]] cuts through the [[North Downs]]) and the west–east [[Vale of Holmesdale]] (a narrow strip of low-lying land between the North Downs and the [[Greensand Ridge]]).<ref name=Crocker_1990_p20>{{harvnb|Crocker|1990|p=20}}</ref><ref name=Bright_1884_p11>{{harvnb|Bright|1884|p=11}}</ref> The highest point in the town is the [[Glory Wood and Devil's Den|Glory Wood]], south east of the centre, where the summit ({{cvt|137|m|ft|sigfig=3}}) is marked by a [[Bronze Age]] [[bowl barrow]].<ref name=NHLE_Glory_Wood_bowl_barrow>{{National Heritage List for England|num=1007881|desc=Bowl barrow in The Glory Wood}}</ref>

The basic plan of the town centre has not changed since [[Middle Ages|medieval times]] (and may be [[Anglo-Saxon]] in origin).<ref name=Robertson_2004>{{cite web |url=https://archaeologydataservice.ac.uk/archiveDS/archiveDownload?t=arch-726-1/dissemination/pdf/dorking/dorking_eus_report.pdf |title=Extensive Urban Survey of Surrey: Dorking |last=Robertson |first=Jane |date=August 2004 |orig-year=2002 |publisher=Surrey County Archaeological Unit |access-date=22 September 2020 |archive-date=2 January 2021 |archive-url=https://web.archive.org/web/20210102102144/https://archaeologydataservice.ac.uk/archiveDS/archiveDownload?t=arch-726-1%2Fdissemination%2Fpdf%2Fdorking%2Fdorking_eus_report.pdf |url-status=live}}</ref> The main streets (the High Street, West Street and South Street) meet at Pump Corner, forming a "<span style="{{Transform-rotate|270}}">&nbsp;Y&nbsp;</span>" shape.<ref name=Bright_1884_p13>{{harvnb|Bright|1884|p=13}}</ref><ref name=Ettinger_1991_pp15-16>{{harvnb|Ettinger|Jackson|Overell|1991|pp=15–16}}</ref> Together, West Street and the High Street run approximately west–east, paralleling the [[Pipp Brook]], a tributary of the Mole, which runs to the north of the centre.<ref name=Ettinger_1991_pp11-13>{{harvnb|Ettinger|Jackson|Overell|1991|pp=11–13}}</ref>

The town is surrounded by the [[Metropolitan Green Belt]] (which also covers the Glory Wood) and is bordered on three sides by the [[Surrey Hills National Landscape]]. Several [[Site of Special Scientific Interest|Sites of Special Scientific Interest]] are close by, including the [[Mole Gap to Reigate Escarpment]], immediately to the north.<ref>{{cite web |url=https://www.surreycc.gov.uk/land-planning-and-development/interactive-map |title=Surrey Interactive Map |author=<!--Not stated--> |date=29 November 2013 |publisher=Surrey County Council |access-date=3 January 2021 |archive-date=13 December 2020 |archive-url=https://web.archive.org/web/20201213055927/https://www.surreycc.gov.uk/land-planning-and-development/interactive-map |url-status=live }}</ref> The [[National Trust for Places of Historic Interest or Natural Beauty|National Trust]] owns several properties in the area, including [[Box Hill, Surrey|Box Hill]],<ref name=NT_Box_Hill>{{cite web |url=https://www.nationaltrust.org.uk/box-hill |title=Box Hill |author=<!--Not stated--> |publisher=National Trust |access-date=3 January 2021 |archive-date=15 August 2020 |archive-url=https://web.archive.org/web/20200815042046/https://www.nationaltrust.org.uk/box-hill |url-status=live}}</ref> [[Leith Hill|Leith Hill Tower]]<ref name=NT_Leith_Hill_Tower>{{cite web |url=https://www.nationaltrust.org.uk/leith-hill-tower-and-countryside |title=Leith Hill Tower and Countryside |author=<!--Not stated--> |publisher=National Trust |access-date=3 January 2021 |archive-date=19 August 2020 |archive-url=https://web.archive.org/web/20200819024359/https://www.nationaltrust.org.uk/leith-hill-tower-and-countryside |url-status=live}}</ref> and [[Polesden Lacey]].<ref name=NT_Polesden>{{cite web |url=https://www.nationaltrust.org.uk/polesden-lacey |title=Polesden Lacey |author=<!--Not stated--> |publisher=National Trust |access-date=3 January 2021 |archive-date=2 January 2021 |archive-url=https://web.archive.org/web/20210102103859/https://www.nationaltrust.org.uk/polesden-lacey |url-status=live}}.</ref>

===Geology===
[[File:Western_Weald_geology_cross_section.png|thumb|Simplified geological cross section of the western Weald, showing how the land was uplifted to form the [[Weald–Artois Anticline|Weald-Artois anticline]] (dashed lines) and the strata as they are today (solid lines).]]

The rock [[stratum|strata]] on which Dorking sits, belong primarily to the [[Lower Greensand Group]]. This group is multilayered and includes the sandy Hythe Beds, the clayey Sandgate Beds and the quartz-rich Folkestone Beds.<ref name=Dines_1933_11-13>{{harvnb|Dines|Edmunds|Chatwin|Stubblefield|1933|pp=11–13}}</ref> The lower greensand was deposited in the [[early Cretaceous]], most likely in a [[anoxic waters|shallow sea with low oxygen levels]]. Over the subsequent 50 million years, other strata were deposited on top of the Lower Greensand, including [[Gault|Gault clay]], [[Upper Greensand Formation|Upper Greensand]] and the [[chalk]] of the North and South Downs.<ref>{{harvnb|Gallois|Edmunds|1965|pp=35–40}}</ref>

Following the [[Cretaceous]], the sea covering the south of England began to retreat and the land was pushed higher. The [[Weald]] (the area covering modern-day south Surrey, south Kent, north Sussex and east Hampshire) was lifted by [[Alpine orogeny|the same geological processes that created the Alps]], resulting in an [[anticline]] which stretched across the [[English Channel]] to the [[Artois|Artois region]] of northern France.<ref>{{harvnb|Gallois|Edmunds|1965|pp=51–53}}</ref> Initially an island, this [[Weald–Artois Anticline|dome-like structure]] was drained by the ancestors of the rivers which today cut through the North and South Downs, including the Mole.<ref>{{harvnb|Gallois|Edmunds|1965|pp=74–77}}</ref> The dome was eroded away over the course of the [[Cenozoic]], exposing the strata beneath and resulting in the [[escarpment]]s of the Downs and the Greensand Ridge.<ref>{{harvnb|Gallois|Edmunds|1965|pp=71–72}}</ref>

In Dorking, the dividing line between the Lower Greensand and Gault clay is marked by the course of the Pipp Brook. In the south of the town, the Hythe Beds take the form of [[Iron-rich sedimentary rocks|iron-rich]], soft, [[grain size|fine-grained]] sandstone,<ref>{{harvnb|Dines|Edmunds|Chatwin|Stubblefield|1933|pp=47–51}}</ref> whereas the Sandgate Beds have a more [[loam]]y composition.<ref>{{harvnb|Dines|Edmunds|Chatwin|Stubblefield|1933|pp=58–59}}</ref> The [[quartz|quartz-rich]] Folkestone Beds have a lower iron content, and contain veins of [[silver sand]] and rose-coloured [[iron-rich sedimentary rocks|ferruginous]] sand.<ref>{{harvnb|Dines|Edmunds|Chatwin|Stubblefield|1933|pp=73–74}}</ref> Running along the north bank of the Pipp Brook (with a width of around {{cvt|200|m|yd|sigfig=1}}) is the outcrop of Gault, a blue-black [[shale|shaly]] clay,<ref>{{harvnb|Dines|Edmunds|Chatwin|Stubblefield|1933|pp=80–82}}</ref> beyond which is a narrow band of Upper Greensand, a hard, grey [[mica|mica-rich]] sandstone.<ref>{{harvnb|Dines|Edmunds|Chatwin|Stubblefield|1933|pp=84–87}}</ref> In the extreme north west of the town, the [[marl]]y Lower Chalk was quarried for [[Lime (material)|lime production]] until the early 20th century.<ref>{{harvnb|Dines|Edmunds|Chatwin|Stubblefield|1933|pp=97–99}}</ref>

[[Ammonoidea|Ammonite fossils]] are found in the north of the town, including ''[[Stoliczkia]]'', ''[[Callihoplites]]'', ''[[Acanthoceras (ammonite)|Acanthoceras]]'' and ''[[Euomphaloceras]]'' species in the Lower Chalk and ''[[Puzosia]]'' species in the Upper Greensand.<ref>{{cite journal |last1=Kennedy |first1=William James |year=1969 |title=The correlation of the Lower Chalk of south-east England |journal=Proceedings of the Geologists' Association |volume=80 |issue=4 |pages=459–560 |doi=10.1016/S0016-7878(69)80033-7|bibcode=1969PrGA...80..459K }}</ref> [[Foraminifera]] fossils have been found in the Hythe Beds adjacent to the Horsham road, to the west of Tower Hill.<ref>{{harvnb|Dines|Edmunds|Chatwin|Stubblefield|1933|p=118}}</ref>