71:. Examination of the sediments and associated fossils allows the deeper centre of the basin to be distinguished from shallower 'platform' areas along its southeastern margins. From the middle Silurian onwards,
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and, in the northwest, the Menai Strait Fault Zone. Its extent to the southwest and northeast is uncertain as these areas are cloaked by more recent rocks.
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comprising the
Pontesford-Linley Fault and Church Stretton Fault which stretch from
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was laid down in the area. To the southeast lay the
Midland Platform (a part of the
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as the sediment mass became unstable from time to time. In addition to the
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of the basin occurred at that time i.e. its uplift and deformation.
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The southeastern limit of the Welsh Basin can be defined as the
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material was derived from the landmass to its southeast
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periods during which a considerable thickness of marine
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within the overall sequence, particularly within the
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Typical of the sediments of the Welsh Basin are the
120:of the Welsh Basin, there are a number of volcanic
139:which outcrop along the middle coastal section of
171:(Keyworth, Nottingham, British Geological Survey)
75:of Avalonia with the more northerly continent of
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182:The Geological History of the British Isles
202:The Geology of Britain: an introduction
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180:Hunter, A. & Easterbrook, G. 2004
16:Historical back-arc depositional basin
184:, The Open University, Milton Keynes
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51:) and to the northwest, within the
23:was a northeast-southwest aligned
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169:British Regional Geology: Wales
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79:occurred giving rise to the
92:Welsh Borderland Fault Zone
25:back-arc depositional basin
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143:and comprise alternating
55:, through what is now
204:Airlife Publishing.
167:Howells, M.F. 2007
81:Caledonian Orogeny
200:Toghill, P. 2000
137:Aberystwyth Grits
126:Ordovician system
118:sedimentary rocks
69:volcanic activity
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228:Geology of Wales
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147:and turbiditic
45:micro-continent
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61:Lake District
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141:Cardigan Bay
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27:during the
21:Welsh Basin
155:References
149:sandstones
133:Llandovery
122:formations
114:turbidites
100:Shropshire
65:island arc
33:Ordovician
145:mudstones
110:Pretannia
85:inversion
77:Laurentia
73:collision
63:, was an
41:sediments
222:Category
59:and the
49:Avalonia
37:Silurian
29:Cambrian
57:Ireland
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83:. The
206:ISBN
186:ISBN
135:age
35:and
19:The
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31:,
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