The geology of the Ballina Syncline

Bowes, George E (1956) The geology of the Ballina Syncline. PhD thesis, University of Glasgow.

Abstract

In early Visean times subsidence began in the Ballina area, and a basin of sedimentation developed whose form and nature were largely controlled by the caledonoid structural lines of the basement. During the first phase of deposition most of the sediments which entered the basin were derived from the north-west, and accumulated in a large delta. Sedimentation and subsidence were greatest near Ballycastle where about 2,000 feet of sandstones, siltstones, shales and limestones are preserved. At Dromore West and Keenagh only a few hundred feet of deltaic deposits occur, and farther east, at Skreen only a few tens of feet. The beds of this delta are referred to the Carboniferous Sandstone. The fauna which they contain indicates a Visean age, probably C2S1. The beds succeeding the deltaic sediments are referred to the Ballina Limestone, and are a series of bedded limestones with thin shale partings. The lateral variation in the thickness of the deltaic beds suggests that the Ballina Limestone facies spread northwestwards when the rate of supply of terrigenous material tb the delta diminished. A sandy-oolitic facies of the Ballina Limestone which occurred near what is now the Ox Mountains Range suggests that a contemporary anticlinal axis was located there. The fauna of the Ballina Limestone consists mainly of corals and brachiopods, and these indicate a lower Visean age, also probably C2S1. Armorican earth movements caused the development of faults and folds in a pattern which was in large measure controlled by the Caledonoid structures of the underlying rocks. Structurally the Ballina Syncline is an area of Carboniferous rocks preserved by downthrow between large faults. In the western part folding is slight, but the rocks have been dislocated by large faults. In the east there are several folds, usually broad with low dips, but occasionally with dips as steep as 50

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Additional Information: Adviser: T Neville George
• Keywords: Geology
• Date of Award: 1956
• Depositing User: Enlighten Team
• Unique ID: glathesis:1956-73448
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 14 Jun 2019 08:56
• Last Modified: 14 Jun 2019 08:56
• URI: https://theses.gla.ac.uk/id/eprint/73448