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Capel Curig
Volcanic Formation, Foel Fras Volcanic Formation, Conwy Rhyolite Volcanic Formation, Foel Grach Basalt Formation, Braich Tu Du Volcanic Formation
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epoch of the
Ordovician period. The Group comprises (in descending order, i.e. oldest last):
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It also includes the Foel Grach Basalt
Formation and the Braich Tu Du Volcanic Formation.
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British
Geological Survey 1:50,000 scale geological map (England & Wales) sheets 106
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and breccias with a variety of volcaniclastic sediments erupted or sedimented during the
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of the Capel Curig
Volcanic Formation exposed on the northeastern face of
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The Group comprises around 1400m thickness of ash flow
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310:http://www.bgs.ac.uk/Lexicon/lexicon.cfm?pub=LLV
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407:United Kingdom geologic formation stubs
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312:(BGS on-line lexicon of rock units)
345:. You can help Knowledge (XXG) by
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273:Conwy Rhyolite Volcanic Formation
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334:This article about a specific
267:Capel Curig Volcanic Formation
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270:Foel Fras Volcanic Formation
392:Ordovician System of Europe
341:in the United Kingdom is a
231:The rocks occur across the
215:. The name is derived from
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247:Lithology and stratigraphy
219:, the highest peak in the
223:range where it outcrops.
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397:Upper Ordovician Series
191:Llewelyn Volcanic Group
92:Nant Ffrancon Formation
21:Llewelyn Volcanic Group
241:Capel Curig Anticline
82:Cwm Eigiau Formation
27:Stratigraphic range
402:Geology of Gwynedd
198:lithostratigraphic
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217:Carnedd Llewelyn
182:Carnedd Llewelyn
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239:and within the
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347:expanding it
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173:Type section
101:approx 1400m
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205:rock strata
386:Categories
281:References
261:Caradocian
195:Ordovician
157:northwest
138:sandstones
134:siltstones
31:Ordovician
29:: Caradoc
339:formation
257:rhyolites
237:Carneddau
221:Carneddau
209:Snowdonia
178:Named for
130:mudstones
126:rhyolites
114:ash flow
106:Lithology
98:Thickness
78:Underlies
70:Sub-units
46:ash-flow
44:Rhyolitic
297:and 119
227:Outcrops
149:Location
142:breccias
88:Overlies
299:Snowdon
233:Snowdon
165:Country
111:Primary
295:Bangor
193:is an
154:Region
253:tuffs
213:Wales
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201:group
168:Wales
159:Wales
122:Other
116:tuffs
64:Group
48:tuffs
343:stub
189:The
60:Type
144:etc
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360:v
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