516 Notices of Memoirs — Prof. Cole — Geology of Belfast. 



forward evidence to show that both are for the most part of Bagshot 

 age, with the exception only of the deposits that have been rearranged 

 in later times. There is, therefore, good reason for referring to 

 the Bagshot series the beds at Combe Pyne, which are evidently 

 in situ, and which possess so many of the features characteristic 

 of that formation.^ 



III. — The Geology of the Country in the Neighbourhood of 

 Belfast.^ By Professor Grenville A. J. Cole, F.G.S. 



BELFAST stands between the lava-plateaux of Cainozoic age in 

 Antrim and the undulating surface of Silurian rocks in county 

 Down. The special interest of the district lies in the preservation 

 of Mesozoic rocks, which elsewhere are scarcely represented in 

 Ireland. Schists and gneisses in the north-east of county Antrim 

 possibly represent Archaean masses refolded during the Caledonian 

 earth-movements. The Caledonian folds gave us the crumpled 

 country of Down, and admitted the granite of Newry and 

 Castlewellan along an axis running north-east and south-west. 

 Both Ordovician and ' Upper Silurian ' (or Gotlandian) strata are 

 represented in this area. The conglomerate of Cushendun is 

 probably of Old Eed Sandstone age ; but the Carboniferous Lime- 

 stone, which is so marked a feature of Ireland as a whole, plays only 

 a small part in the north-eastern counties. The Carboniferous strata 

 of Ballycastle, west of Fair Head, are mainly sandstones with 

 intercalated coal-seams, on the same horizon as the Calciferous 

 Sandstone of the South of Scotland. 



A patch of marine Permian strata occurs east of Belfast, at 

 Holywood ; and the British type of Trias, red rocks with salt and 

 gypsum, is well represented under the basalt capping that has 

 preserved it. The Ehsetic sea spread into this area, and terminated 

 far west against the Londonderry highlands : the Lias also began to 

 form, and is now finely exposed at Waterloo, close to Larne. It is 

 questionable if higher Jurassic beds than those now left to us were 

 ever laid down in this region ; elevation and denudation certainly 

 set in early, and the country remained dry land until the middle of 

 Cretaceous times. Then, in the westernmost extension of the great 

 Chalk sea, the sands, conglomerates, and white limestone of Antrim 

 were deposited, representing the Upper Cretaceous of England in a 

 thickness of about 100 feet. The cliffs of hardened chalk, between 

 red basement-beds of Trias and the black basalt scarp above, form, 

 in Glenariff and Murlough Bay, one of the most beautiful contrasts 

 in our Islands. It is clear that in early Eocene times both the 

 counties of Antrim and Down were covered with a rolling series of 

 Chalk uplands, resembling on a less massive scale our present 

 Salisbury Plain. This quiet and newly upheaved country was 

 destined to be devastated by volcanic action, more continuous and 

 extensive than had been seen in the British Isles since Old Eed 

 Sandstone times. 



^ Particulars of tlie sections are given in the Summary of Progress of the 

 Geological Survey for 1901, pp. 53-59. 



2 Eead before the British Association, Belfast, Sept. 1902, in Section C (Geology), 



