| Previous Site | Next Site |
Earth Science Conservation Review
| White House Port, Cloghy | Down |
| Site number: | 654 | ||
| Locality Type: | Foreshore | Status: | ASSI |
| Grid Reference: | J645552 Centroid | ||
| Google maps: | 54.41919,-5.46572 | ||
| County: | Down | Council area: | Ards & North Down Borough Council |
| Period: | Silurian | ||
| Lithostrat: | Hawick Group | ||
| Site Description | |
|---|---|
| Introduction: | |
White House Port is situated on the Irish Sea coast of the Ards Peninsula, about 1.3km south of the village of Cloghy. Access is via a lane leading to the shore at the southern end of the village (Fig. 23). The site contains numerous accessible outcrops of folded turbidite facies rocks, which are part of the Hawick Group (Silurian). Up to four separate phases of deformation are evident. | |
| Description: | |
This site contains a diverse set of fold structures and associated cleavages representing up to four phases of Caledonian deformation. Near the end of the small concrete slipway, an upright isoclinal F1 anticline is refolded about a south-verging F2 fold pair with a short limb and axial surface inclined gently south. The F2 folds have axial-planar cleavage (S2) which crenulates S1. Elsewhere at this locality there are examples of cleaved dykes belonging to the 'Older Series' lamprophyres as defined by Reynolds (1931). One example, north of the isoclinal hinge, appears to carry an S2 cleavage and a steeply inclined foliation, which is sub-parallel to S1. Elsewhere in the bay many thin lamprophyre intrusions have been affected by F2 folds and kink bands (F4) but are never seen to be folded about the numerous F1 structures (Anderson et al., 1978). The structures at White House Port are fairly typical of Caledonian deformation seen elsewhere in the Silurian rocks of County Down. The principle structures are related to D1 and were formed during NW-directed subduction of the Iapetus Oceanic crust which resulted in the formation of an imbricated stack of fault-bounded tectonic blocks. Subsequent deformations were related to the final closure of Iapetus and subsequent uplift of the accretionary prism. Across the Down-Longford Belt, Caledonian deformation was accompanied by a very-low grade regional metamorphism during which the rocks were metamorphosed under prehnite-pumpellyite facies conditions. | |
| Notes: | |
For general information on the Structural Geology of Northern Ireland, directions to other Structural Geology sites and an extensive reference list see Key Site 641 - Introduction to the Structural Geology of N. Ireland. The full range of ESCR site relating to the Lower Palaeozoic are as follows: Outer Ards Stratigraphic, Palaeontological and Structural sites Coalpit Bay – Lower Palaeozoic (record no. 1350) Helen’s Bay – Grey Point – Lower Palaeozoic (record no. 1351) Kearney Point – Knockinelder Bay – Lower Palaeozoic (record no. 1352) Orlock Bridge – Lower Palaeozoic (record no. 1353) Tieveshilly – Carrstown – Lower Palaeozoic (record no. 1354) Orlock Bridge - Structural (record no. 652) Whiskin Rocks - Structural (record no. 653) White House Port, Cloghy - Structural (record no. 654) Knockinelder Bay and Kearney Point - Structural (record no. 655) Millin Bay - Structural (record no. 656) Pomeroy area Craigbardahessiagh and Bardahessiagh River – Palaeontology (record no. 29) Lime Hill Farm – Palaeontology (record no. 33) Little River and Slate Quarry Bridge – Palaeontology (record no. 31) | |
| Keywords | |
|---|---|
| Rocks: | Turbidite, Lamprophyre |
| Structures: | anticline, dyke, fold pairs, cleavage, fold, fold hinge, kink band |
| Relations: | Marine sediments |
| Access | |
|---|---|
| Approach: | Access is via a lane leading to the shore at the southern end of the village (Fig. 23). |
| Record type: | ESCR report | Recorded by: | T.P. Johnston |
| Entered by: | E M Porter | ||
| Last updated: | 23/09/03 | ||
| Enlander, I., Dempster, M. & Doughty, P., 2026. White House Port, Cloghy, County Down, site details. [In] Earth Science Conservation Review. https://www.habitas.org.uk/escr/site.php?item=654. Accessed on 2026-11-07. |
| Previous Site | Next Site |