All Outputs (29)

Overprinting orogenic events, ductile extrusion and strain partitioning during Caledonian transpression, NW Mainland Shetland (2024)
Journal Article
Armitage, T. B., Holdsworth, R. E., Strachan, R. A., Dempsey, E. D., Walker, R. J., Alvarez-Ruiz, D. T., & Lloyd, G. E. (2024). Overprinting orogenic events, ductile extrusion and strain partitioning during Caledonian transpression, NW Mainland Shetland. Journal of Structural Geology, 180, Article 105088. https://doi.org/10.1016/j.jsg.2024.105088

A 3.6 km thick stack of mid-crustal deformed Precambrian rocks is associated with the North Roe Nappe (NRN) and Walls Boundary Fault in the northernmost Scottish Caledonides on NW Mainland Shetland. The greenschist- to amphibolite-facies rocks displa... Read More about Overprinting orogenic events, ductile extrusion and strain partitioning during Caledonian transpression, NW Mainland Shetland.

Ikaite formation in streams affected by steel waste leachate: First report and potential impact on contaminant dynamics (2023)
Journal Article
Bastianini, L., Rogerson, M., Brasier, A., Prior, T. J., Hardman, K., Dempsey, E., Bird, A., & Mayes, W. M. (2024). Ikaite formation in streams affected by steel waste leachate: First report and potential impact on contaminant dynamics. Chemical Geology, 644, Article 121842. https://doi.org/10.1016/j.chemgeo.2023.121842

Highly alkaline (pH 9–12) waters can arise from a range of globally significant and environmentally impactful industrial processes such as lime, steel and cement production, alumina refining and energy generation (e.g. combustion ashes). Such residue... Read More about Ikaite formation in streams affected by steel waste leachate: First report and potential impact on contaminant dynamics.

An onshore-offshore interpretation of structures in the Devonian rocks of the Pentland Firth, Scotland using high resolution bathymetry and drone-enabled field observations. (2023)
Journal Article
Utley, T. A., Holdsworth, R. E., Walker, R. J., Dempsey, E. D., McCaffrey, K. J., Dichiarante, A., & Jones, T. L. (2023). An onshore-offshore interpretation of structures in the Devonian rocks of the Pentland Firth, Scotland using high resolution bathymetry and drone-enabled field observations. Journal of Structural Geology, 174, Article 104922. https://doi.org/10.1016/j.jsg.2023.104922

Strong tidal currents in the Pentland Firth separating NE Scotland and Orkney have stripped recent seafloor sediments revealing geological structures in parts of the Devonian Orcadian Basin that are otherwise limited to narrow coastal outcrops. Here... Read More about An onshore-offshore interpretation of structures in the Devonian rocks of the Pentland Firth, Scotland using high resolution bathymetry and drone-enabled field observations..

Eclogites and basement terrane tectonics in the northern arm of the Grenville orogen, NW Scotland (2023)
Journal Article
Bird, A., Thirlwall, M., Strachan, R. A., Millar, I. L., Dempsey, E. D., & Hardman, K. (2023). Eclogites and basement terrane tectonics in the northern arm of the Grenville orogen, NW Scotland. Geoscience Frontiers, 14(6), Article 101668. https://doi.org/10.1016/j.gsf.2023.101668

The presence of eclogites within continental crust is a key indicator of collisional orogenesis. Eclogites within the Eastern Glenelg basement inlier of the Northern Highland Terrane (NHT) have been re-dated in order to provide more accurate constrai... Read More about Eclogites and basement terrane tectonics in the northern arm of the Grenville orogen, NW Scotland.

Older than you think: using U–Pb calcite geochronology to better constrain basin-bounding fault reactivation, Inner Moray Firth Basin, western North Sea (2023)
Journal Article
Tamas, A., Holdsworth, R. E., Tamas, D. M., Dempsey, E. D., Hardman, K., Bird, A., Roberts, N. M., Lee, J., Underhill, J. R., McCarthy, D., McCaffrey, K. J., & Selby, D. (2023). Older than you think: using U–Pb calcite geochronology to better constrain basin-bounding fault reactivation, Inner Moray Firth Basin, western North Sea. Journal of the Geological Society, 180(5), Article jgs2022-166. https://doi.org/10.1144/jgs2022-166

Like many rift basins worldwide, the Inner Moray Firth Basin (IMFB) is bounded by major reactivated fault zones, including the Helmsdale Fault and the Great Glen Fault (GGF). The Jurassic successions exposed onshore close to these faults at Helmsdale... Read More about Older than you think: using U–Pb calcite geochronology to better constrain basin-bounding fault reactivation, Inner Moray Firth Basin, western North Sea.

Strike-slip influenced stratigraphic and structural development of the Foula Sandstone Group, Shetland: implications for offshore Devonian basin development on the northern UK continental shelf (2023)
Journal Article
Utley, T. A., Holdsworth, R. E., Blackbourn, G. A., Dempsey, E., Strachan, R. A., McCaffrey, K. J., Morton, A. C., Bird, A. F., Jones, R. R., Saßnowski, A., & Walker, R. J. (2023). Strike-slip influenced stratigraphic and structural development of the Foula Sandstone Group, Shetland: implications for offshore Devonian basin development on the northern UK continental shelf. Journal of the Geological Society, 180(3), Article jgs2022-148. https://doi.org/10.1144/jgs2022-148

The island of Foula, located 25 km SW of Shetland, preserves a gently folded, 1.6 km thick sequence of Middle Devonian sandstones spectacularly exposed in kilometre-long cliff sections >350 m high. These rocks unconformably overlie likely Precambrian... Read More about Strike-slip influenced stratigraphic and structural development of the Foula Sandstone Group, Shetland: implications for offshore Devonian basin development on the northern UK continental shelf.

Using UAV-Based Photogrammetry Coupled with In Situ Fieldwork and U-Pb Geochronology to Decipher Multi-Phase Deformation Processes: A Case Study from Sarclet, Inner Moray Firth Basin, UK (2023)
Journal Article
Tamas, A., Holdsworth, R. E., Tamas, D. M., Dempsey, E. D., Hardman, K., Bird, A., Underhill, J. R., McCarthy, D., McCaffrey, K. J., & Selby, D. (2023). Using UAV-Based Photogrammetry Coupled with In Situ Fieldwork and U-Pb Geochronology to Decipher Multi-Phase Deformation Processes: A Case Study from Sarclet, Inner Moray Firth Basin, UK. Remote Sensing, 15(3), Article 695. https://doi.org/10.3390/rs15030695

Constraining the age of formation and repeated movements along fault arrays in superimposed rift basins helps us to better unravel the kinematic history as well as the role of inherited structures in basin evolution. The Inner Moray Firth Basin (IMFB... Read More about Using UAV-Based Photogrammetry Coupled with In Situ Fieldwork and U-Pb Geochronology to Decipher Multi-Phase Deformation Processes: A Case Study from Sarclet, Inner Moray Firth Basin, UK.

Mid-crustal reactivation processes linked to frictional melting and deep void development during seismogenic slip: examples from the Lewisian Complex, NW Scotland (2022)
Journal Article
Hardman, K., Holdsworth, R. E., Scott, L., Dempsey, E., & McCaffrey, K. J. W. (in press). Mid-crustal reactivation processes linked to frictional melting and deep void development during seismogenic slip: examples from the Lewisian Complex, NW Scotland. Journal of the Geological Society, https://doi.org/10.1144/jgs2022-037

Exhumed examples of ancient fault voids formed during seismic slip at depths > 10 km are well preserved in the Assynt Terrane of the Lewisian Complex, NW Scotland. They are interpreted to have formed during regional Mesoproterozoic (ca 1.55 Ga; ‘Assy... Read More about Mid-crustal reactivation processes linked to frictional melting and deep void development during seismogenic slip: examples from the Lewisian Complex, NW Scotland.

Caledonian hot zone magmatism in the ‘Newer Granites’: insight from the Cluanie and Clunes plutons, Northern Scottish Highlands (2022)
Journal Article
Milne, E. J., Neill, I., Bird, A. F., Millar, I. L., McDonald, I., Dempsey, E. D., Olive, V., Odling, N., & Waters, E. C. (2023). Caledonian hot zone magmatism in the ‘Newer Granites’: insight from the Cluanie and Clunes plutons, Northern Scottish Highlands. Journal of the Geological Society, 180(2), Article jgs2022-076. https://doi.org/10.1144/jgs2022-076

Scottish ‘Newer Granites’ record the evolution of the Caledonides resulting from Iapetus subduction and slab breakoff during the Silurian–Devonian Scandian Orogeny, but relationships between geodynamics, petrogenesis and emplacement are incomplete. L... Read More about Caledonian hot zone magmatism in the ‘Newer Granites’: insight from the Cluanie and Clunes plutons, Northern Scottish Highlands.

Correlating deformation events onshore and offshore in superimposed rift basins: The Lossiemouth Fault Zone, Inner Moray Firth Basin, Scotland (2022)
Journal Article
Tamas, A., Holdsworth, R. E., Underhill, J. R., Tamas, D. M., Dempsey, E. D., McCarthy, D. J., …Selby, D. (in press). Correlating deformation events onshore and offshore in superimposed rift basins: The Lossiemouth Fault Zone, Inner Moray Firth Basin, Scotland. Basin Research, https://doi.org/10.1111/bre.12661

The separation and characterisation of different deformation events in superim-posed basins can be challenging due to the effects of overprinting and/or fault reactivation, combined with a lack of detailed geological or geophysical data. This paper s... Read More about Correlating deformation events onshore and offshore in superimposed rift basins: The Lossiemouth Fault Zone, Inner Moray Firth Basin, Scotland.

New onshore insights into the role of structural inheritance during Mesozoic opening of the Inner Moray Firth Basin, Scotland (2021)
Journal Article
Tamas, A., Holdsworth, R. E., Underhill, J. R., Tamas, D. M., Dempsey, E. D., Hardman, K., …Selby, D. (2022). New onshore insights into the role of structural inheritance during Mesozoic opening of the Inner Moray Firth Basin, Scotland. Journal of the Geological Society, 179(2), Article 066. https://doi.org/10.1144/jgs2021-066

The Inner Moray Firth Basin (IMFB) forms the western arm of the North Sea trilete rift system that initiated mainly during the Late Jurassic–Early Cretaceous with the widespread development of major NE–SW-trending dip-slip growth faults. The IMFB is... Read More about New onshore insights into the role of structural inheritance during Mesozoic opening of the Inner Moray Firth Basin, Scotland.

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 (2021)
Journal Article
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

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 u... Read More about 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.

Fracture attribute scaling and connectivity in the Devonian Orcadian Basin with implications for geologically equivalent sub-surface fractured reservoirs (2020)
Journal Article
Dichiarante, A. M., McCaffrey, K. J. W., Holdsworth, R. E., Bjørnarå, T. I., & Dempsey, E. D. (2020). Fracture attribute scaling and connectivity in the Devonian Orcadian Basin with implications for geologically equivalent sub-surface fractured reservoirs. Solid Earth, 11(6), 2221-2244. https://doi.org/10.5194/se-11-2221-2020

Fracture attribute scaling and connectivity datasets from analogue systems are widely used to inform sub-surface fractured reservoir models in a range of geological settings. However, significant uncertainties are associated with the determination of... Read More about Fracture attribute scaling and connectivity in the Devonian Orcadian Basin with implications for geologically equivalent sub-surface fractured reservoirs.

A bigger splat: The catastrophic geology of a 1.2-b.y.-old terrestrial megaclast (2020)
Journal Article
Killingback, Z., Holdsworth, R. E., Walker, R. J., Nielsen, S., Dempsey, E., & Hardman, K. (2020). A bigger splat: The catastrophic geology of a 1.2-b.y.-old terrestrial megaclast. Geology, https://doi.org/10.1130/G48079.1

Rockfalls are relatively little described from the ancient geological record, likely due to their poor preservation potential. At Clachtoll, northwest Scotland, a megaclast (100 m × 60 m × 15 m) of Neoarchean Lewisian gneiss with an estimated mass of... Read More about A bigger splat: The catastrophic geology of a 1.2-b.y.-old terrestrial megaclast.

The nature and significance of rift-related, near-surface fissure fill networks in fractured carbonates below regional unconformities (2020)
Journal Article
Hardman, K., Holdsworth, R. E., Dempsey, E., & McCaffrey, K. (2020). The nature and significance of rift-related, near-surface fissure fill networks in fractured carbonates below regional unconformities. Journal of the Geological Society, https://doi.org/10.1144/jgs2020-074

Hosted in carbonate and crystalline basement rocks below regional unconformities, fissure-fill networks are a widely recognized, but relatively little described near-surface phenomenon (< 1-2km). Faults and fractures in otherwise tight Devonian carbo... Read More about The nature and significance of rift-related, near-surface fissure fill networks in fractured carbonates below regional unconformities.

The nature and age of Mesoproterozoic strike-slip faulting based on Re-Os geochronology of syn-tectonic copper mineralization, Assynt Terrane, NW Scotland (2020)
Journal Article
Holdsworth, R. E., Selby, D., Dempsey, E., Scott, L., Hardman, K., Fallick, A., & Bullock, R. (in press). The nature and age of Mesoproterozoic strike-slip faulting based on Re-Os geochronology of syn-tectonic copper mineralization, Assynt Terrane, NW Scotland. Journal of the Geological Society, jgs2020-011. https://doi.org/10.1144/jgs2020-011

The nature and age of basement host rocks and fissure fills in the Lancaster field fractured reservoir, West of Shetland (2019)
Journal Article
Holdsworth, R. E., Trice, R., Hardman, K., McCaffrey, K. J., Morton, A., Frei, D., Dempsey, E., Bird, A., & Rogers, S. (2020). The nature and age of basement host rocks and fissure fills in the Lancaster field fractured reservoir, West of Shetland. Journal of the Geological Society, 177(5), 1057-1073. https://doi.org/10.1144/jgs2019-142

Hosting up to 3.3 billion barrels of oil in place, the upfaulted Precambrian crystalline rocks of the Lancaster field, offshore west of Shetland, give key insights into how fractured hydrocarbon reservoirs can form in such old rocks. The Neoarchean (... Read More about The nature and age of basement host rocks and fissure fills in the Lancaster field fractured reservoir, West of Shetland.

Natural fracture propping and earthquake-induced oil migration in fractured basement reservoirs (2019)
Journal Article
Holdsworth, R. E., McCaffrey, K. J. W., Dempsey, E., Roberts, N. M. W., Hardman, K., Morton, A., Feely, M., Hunt, J., Conway, A., & Robertson, A. (2019). Natural fracture propping and earthquake-induced oil migration in fractured basement reservoirs. Geology, 47(8), 700-704. https://doi.org/10.1130/G46280.1

The geological processes that create fluid storage capacity and connectivity in global fractured basement reservoirs are poorly understood compared to conventional hydrocarbon plays. Hosting potentially multi-billion barrels of oil, the upfaulted P... Read More about Natural fracture propping and earthquake-induced oil migration in fractured basement reservoirs.

The Neoarchaean Uyea Gneiss Complex, Shetland: an onshore fragment of the Rae Craton on the European Plate (2019)
Journal Article
Kinny, P., Strachan, R., Fowler, M., Clark, C., Davis, S., Jahn, I., Taylor, R., Holdsworth, R., & Dempsey, E. (2019). The Neoarchaean Uyea Gneiss Complex, Shetland: an onshore fragment of the Rae Craton on the European Plate. Journal of the Geological Society, Article 017. https://doi.org/10.1144/jgs2019-017

A tract of amphibolite facies granitic gneisses and metagabbros in northern Shetland, U.K., is here named the Uyea Gneiss Complex. Zircon U–Pb dating indicates emplacement of the igneous protoliths of the complex c. 2746–2726 Ma, at a later time than... Read More about The Neoarchaean Uyea Gneiss Complex, Shetland: an onshore fragment of the Rae Craton on the European Plate.

Coseismic ultramylonites: An investigation of nanoscale viscous flow and fault weakening during seismic slip (2019)
Journal Article
Pozzi, G., De Paola, N., Holdsworth, R. E., Bowen, L., Nielsen, S. B., & Dempsey, E. D. (2019). Coseismic ultramylonites: An investigation of nanoscale viscous flow and fault weakening during seismic slip. Earth and planetary science letters, 516, 164-175. https://doi.org/10.1016/j.epsl.2019.03.042

Faults weaken during the propagation of earthquakes due to the onset of thermally-activated mechanisms, which vary depending on the rock type. Recent experimental work suggests that carbonate-hosted faults are lubricated by viscous flow in nano-granu... Read More about Coseismic ultramylonites: An investigation of nanoscale viscous flow and fault weakening during seismic slip.