Skip to main content

Research Repository

Advanced Search

A revised age, structural model and origin for the North Pennine Orefield in the Alston Block, northern England: intrusion (Whin Sill)-related base metal (Cu–Pb–Zn–F) mineralization

Dempsey, E. D.; Holdsworth, R. E.; Selby, D.; Bird, A.; Young, B.; Cornu, C. Le

Authors

Profile Image

Dr Eddie Dempsey E.Dempsey@hull.ac.uk
Senior Lecturer in Structural Geology and Geohazards

R. E. Holdsworth

D. Selby

B. Young

C. Le Cornu



Abstract

Mineralization and associated fluid migration events in the c. 1500 km2 North Pennine Orefield (NPO) are known to be associated with tectonic activity, but the age of these tectonic events and origins of the base metal sulfide mineralization remain unresolved. New fieldwork in the Alston Block shows that mineralization post-dates a weakly developed phase of north–south shortening consistent with far-field Variscan basin inversion during the late Carboniferous. New observations of field relationships, coupled with microstructural observations and stress inversion analyses, together with Re–Os sulfide geochronology show that the vein-hosted mineralization (apart from barium minerals) was synchronous with a phase of north– south extension and east–west shortening coeval with emplacement of the Whin Sill (c. 297–294 Ma). Thus the development of the NPO was related to an early Permian regional phase of transtensional deformation, mantle-sourced hydrothermal mineralization and magmatism in northern Britain. Previously proposed Mississippi Valley Type models, or alternatives relating mineralization to the influx of Mesozoic brines, can no longer be applied to the development of the NPO in the Alston Block. Our findings also mean that existing models for equivalent base metal sulfide fields worldwide (e.g. Zn–Pb districts of Silesia, Poland and Tennessee, USA) may need to be reassessed.

Citation

Dempsey, E. D., Holdsworth, R. E., Selby, D., Bird, A., Young, B., & Cornu, C. L. (2021). A revised age, structural model and origin for the North Pennine Orefield in the Alston Block, northern England: intrusion (Whin Sill)-related base metal (Cu–Pb–Zn–F) mineralization. Journal of the Geological Society, 178(4), Article jgs2020-226. https://doi.org/10.1144/jgs2020-226

Journal Article Type Article
Acceptance Date Jan 26, 2021
Online Publication Date Feb 4, 2021
Publication Date 2021-07
Deposit Date Nov 3, 2021
Publicly Available Date Nov 3, 2021
Journal Journal of the Geological Society
Print ISSN 0016-7649
Electronic ISSN 2041-479X
Publisher Geological Society
Peer Reviewed Peer Reviewed
Volume 178
Issue 4
Article Number jgs2020-226
DOI https://doi.org/10.1144/jgs2020-226
Keywords Geology
Public URL https://hull-repository.worktribe.com/output/3867202

Files

Published article (12.9 Mb)
PDF

Copyright Statement
© 2021 The Author(s). Published by The Geological Society of London http://creativecommons.org/licenses/by/4.0/
This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 License (http://creativecommons.org/licenses/by/4.0/)



You might also like



Downloadable Citations