Geophysical surveys to help map buried igneous intrusions, Snowdonia, North Wales, UK

Moseley, DB; Pringle, JK; Haslam, RB; Egan, SS; Rogers, SL; Gertisser, R; Cassidy, NJ; Stimpson, I

Abstract

The geology of the Snowdonia National Park in North Wales comprises a mixture of Lower Palaeozoic shallow marine sediments, acidic igneous rocks and basic intrusions of the Welsh Basin that were subsequently deformed during the Caledonian Orogeny. Thin igneous intrusions are challenging to map due to variable surface exposures, their intrusive origin, structural deformation and burial by glacial sediments. This study used a combination of traditional geological techniques, near-surface geophysical surveys and remote sensing to detect and map a buried dolerite sheet intrusion. Both simple and mathematical analysis of magnetic anomalies and numerical modelling allowed the dolerite position, depths and target widths to be determined. Results showed that calibrated magnetic surveys can characterise buried igneous bodies in such mountainous environments.

Citation

Moseley, D., Pringle, J., Haslam, R., Egan, S., Rogers, S., Gertisser, R., Cassidy, N., & Stimpson, I. (2015). Geophysical surveys to help map buried igneous intrusions, Snowdonia, North Wales, UK. Geology Today, 109 -115 (6). https://doi.org/10.1111/gto.12096

• Journal Article Type: Article
• Publication Date: May 15, 2015
• Journal: Geology Today
• Print ISSN: 0266-6979
• Electronic ISSN: 1365-2451
• Publisher: Wiley
• Pages: 109 -115 (6)
• DOI: https://doi.org/10.1111/gto.12096
• Keywords: dolerite sheet intrusion
• Public URL: https://keele-repository.worktribe.com/output/404050
• Publisher URL: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291365-2451