The stratigraphy and setting of the Precambrian rocks of the Llangynog Inlier, Dyfed, South Wales
Article Abstract:
Cutting of new forestry tracks resulted in new exposures of Precambrian rocks of the Llangynog Inlier of South Wales and has allowed the first detailed geologic mapping since the early 1900s. There is a 1100 meter thick succession within the Precambrian rocks with the oldest rocks of the area some 350-400 meters of rhyolitic lavas. Little of their original texture remains. The oldest layers are succeeded by deposits of volcaniclastic siltstones which show evidence of deposition during the Ediacaran.
Publication Name: Geological Magazine
Subject: Earth sciences
ISSN: 0016-7568
Year: 1993
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Major northwest-directed Caledonian thrusting and folding in Precambrian rocks, northwest Mayo, Ireland
Article Abstract:
A study of the North West Mayo Inlier in Ireland, with elongation along the east to northeast direction, through structural mapping indicates pre-Caledonian folds and deformations directed west to northwest. The mafic dykes are deformed due to the disturbance of existing structures to shear zones. A major portion of the inlier constitutes flat-lying zones, which are D2 in age. A crustal scale ramp zone contains the D2 folding, the deformation of the ramp leading to F1 folds.
Publication Name: Geological Magazine
Subject: Earth sciences
ISSN: 0016-7568
Year: 1995
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Geochemical character of Neoproterozoic volcanic rocks in southwest Wales
Article Abstract:
The few volcanic rocks of Neoproterozoic origin in Wales and the Welsh Borderland lie along the main fault systems of the Lower Palaeozoic Welsh Basin. These rocks are similar to the Avalonian rocks found in eastern North America. Much research has been done on the rocks in North Wales and the Borderland, with rocks in South Wales being neglected for the most part. Volcanic rocks in South Wales are analyzed.
Publication Name: Geological Magazine
Subject: Earth sciences
ISSN: 0016-7568
Year: 1995
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