Editing Port Talbot (section)

==Geology==
Port Talbot has a variety of bedrock and drift types.<ref>[http://www.bgs.ac.uk/lexicon/lexicon.cfm?pub=PES The BGS Lexicon of Named Rock Units — Result Details] (Retrieved: 18 June 2013)</ref><ref>[http://www.bgs.ac.uk/research/ukgeology/walesMap.html National Minerals Map of Wales] (Retrieved: 18 June 2013)</ref>
[[File:Margamabbey-wyrdlight-7458.jpg|thumb|[[Margam Abbey]]]]

===Bedrock geology===
South East of Port Talbot is dominated by [[Pennant sandstone]] which forms this high relief area including Mynydd Margam, Mynydd Dinas and the other mountains. The pennant sandstone is made up of two formations which are the Rhondda Member and Brithdir Member. The sandstone formed in [[Carboniferous]] swamps 300 million years ago. Pennant sandstone is a micacous sandstone which has a brown colouration with areas of red staining where iron from [[pyrite]] in coal has weathered creating a rust colouration.<ref>{{cite web |title=The Geological Society of London - A stroll along the prom – Swansea Bay |url=https://www.geolsoc.org.uk/GowerTour1 |website=www.geolsoc.org.uk |publisher=The Geological Society |access-date=26 October 2022}}</ref>

Lower land areas are predominantly Pennant sandstone within the [[South Wales Coal Measures Group]].{{citation needed|date=December 2016}}

===Drift geology===
There is a variety of drift deposits in Port Talbot. Sandfields area of Port Talbot is built upon blown sand and [[tidal flat]] deposits. These were deposited by the wind via [[aeolian processes]] and the water by [[fluvial processes]]. Velindre area of Port Talbot is built upon an alluvial fan deposit. This deposit formed during the last glacial period 14,000 years ago. Baglan Road in Port Talbot is built upon glacial till from the [[Last glacial period|Devensian]] period. Till, also known as [[boulder clay]], is a mix of unconsolidated sediment with a range of grain sizes. This forms as the fronts of glaciers rapidly deposit material due to melting. Cwmafan in Port Talbot is built upon [[Alluvium|alluvial]] and [[glaciofluvial deposits]], formed from glacial [[meltwater]]. Baglan Moors, Fairfield and Port Talbot town centre are built upon tidal flat deposits (tides were higher 12,000 years ago allowing sandy deposits to accumulate).{{citation needed|date=December 2016}}

===Economic geology===
Coal seams within the Pennant sandstone run north west-south-east and east–west. The coal seams arise from the South Wales Middle Coal Measures Formation, South Wales Upper Coal Measures Formation, South Wales Lower Coal Measures Formation, Rhondda Member and Brithdir Member. Pennant sandstone is an excellent construction rock and road stone.{{citation needed|date=December 2016}}

===Structural geology===
Faults have an orientation of North West-South East, east–west and north–south. All are normal faults which form extension processes.{{citation needed|date=December 2016}} There are also many marine fossils bands.

===Bio-stratigraphy/palaeontology===
Marine fossils found in Port Talbot region include species of bivalves, gastropods and brachiopods. Terrestrial fossils include fern tree branches, trunks, leaves and roots. Traces of organism footprints can also be found.<ref>{{cite web |url=http://www.fossiel.net/informatie/glossary.php |title=Information about fossils: Glossary |publisher=Fossiel.net |access-date=6 September 2013 |archive-date=23 October 2013 |archive-url=https://web.archive.org/web/20131023081725/http://www.fossiel.net/informatie/glossary.php |url-status=dead }}</ref><ref name="autogenerated1">British Geological Society Map, Swansea and Port Talbot region</ref>

===Engineering geology===
The [[Drift (geology)|drift geology]] average thickness is between {{convert|3|and|20|m|ft|round=5|0}}. Several [[Landslide|landslips]] occur in the highlands including many bole holes historically made for the construction of the M4 motorway, [[steelworks]] and coal mines.<ref name="autogenerated1"/>

===Hydro-geology ===
Rivers in the region are fault guided meaning that they flow is highly influenced by a structural weakness called a fault. Several natural springs occur in the highland regions with a neutral to slightly acidic ph values. Natural [[groundwater]] levels varies from {{convert|10|m|ft|round=5}} below the Taibach area of Port Talbot to over {{convert|20|m|ft|round=5}}. Rivers in the region including the River Afan (Aberafan), River Neath (Baglan Bay), [[Nant Ffrwdwyllt|Ffrwdwyllt]] (Taibach), Arnallt Brook (Taibach), Baglan Brook (Baglan), River Kenfig (Morfa Beach) and other rivers are fast flowing and are highly influenced by their mouths (end of the rivers, tidal region). A spout can be found in Baglan Park in the Baglan region of Port Talbot. Many open and uncovered reservoirs exist in the region. Water has been channelled into ditches in industrial areas of Port Talbot.<ref name="autogenerated1"/><ref>Ordnance Survey Map, Port Talbot Region,2011</ref>