The naturea nda ge ofthe Cenozoic compressional/transpressionaldeformation withint he NE Faroe-ShetlandB asin,the Wyville-Thomson Ridge andH atton Bankareashaveb eeninvestigated, primarily usingseismic reflection data.Inall three areas,the foldsreach approximately 2to4kminamplitude and40kmin wavelength.Early andmid-Eocenec ompressional/transpressionaldeformation affected the Hatton Banka nd Wyville-Thomson Ridge areas,andfoldingwaslocally activeevenearlier,duringPaleocene/Cretaceous times. However,the mainCenozoic compressional/transpressionalt ectonism thataffected the Hatton Banka rea was coevalw ithd evelopment ofthe regionalLateE oceneU nconformity (C30),a ndwithc hangesins preading geometriesandaphaseofaccelerated subsidence inthe Rockall Basin. Withinthe NE Atlantic margin,WNWto NW-trendinglineaments/transferz onesanda ssociated oceanic fracturezonesfacilitatesignificant structural segmentation. Offsets int he continent-oceanboundary alongH atton Bankprobably reflectinherited basin architecture, andmany Cenozoic foldsint he Hatton Bank, Wyville-Thomson Ridge andN EF aroe-Shetland Basinareasareconsidered to mainly reflectcompressionalbuttressingagainst pre-existingstructures. However, relatively small lateraldisplacements probably occurred alongsomereactivated transferz onesfollowing continentalbreak-up. Paleocene-Eocenecompressional/transpressionaldeformation mayhaveaffected parts of the Faroe-ShetlandB asin,b ut seismic resolution ofthisisl argely masked byp ervasivepolygonalfaulting. Significant,e arlyt om id-Miocenec ompressional/transpressionaldeformation isr ecordedi nt he NE Faroe-ShetlandB asin,a ndmayalso havee xerted amajor influence on the Wyville-Thomson Ridge and surroundingarea.Inparticular,mid-Miocenegrowthofthe FaroeBankChannelsynclinemayhaveresulted in major changesinn orthern hemisphered eep-oceancirculation witha ssociated impacto nglobalclimate.Compressional/transpressionaldeformation appears to havecontinued into Pliocene-?Recent timesandresulted int he development offeaturessuch asthe Pilot WhaleAnticlineanda ssociated mudvolcanoes/diapirs.

An updated magnetic anomaly grid of the NE Atlantic and an improved database of magnetic anomaly and fracture zone identifications allow the kinematic history of this region to be revisited. At break-up time, continental rupture occurred parallel to the Mesozoic rift axes in the south, but obliquely to the previous rifting trend in the north, probably due to the proximity of the Iceland plume at 57-54 Ma.The new oceanic lithosphere age grid is based on 30 isochrons (C) from C24n old (53.93 Ma) to C1n old (0.78 Ma), and documents ridge reorganizations in the SE Lofoten Basin, the Jan Mayen Fracture Zone region, in Iceland and offshore Faroe Islands. Updated continent -ocean boundaries, including the Jan Mayen microcontinent, and detailed kinematics of the EocenePresent Greenland-Eurasia relative motions are included in this model.Variations in the subduction regime in the NE Pacific could have caused the sudden northwards motion of Greenland and subsequent Eurekan deformation. These events caused seafloor spreading changes in the neighbouring Labrador Sea and a decrease in spreading rates in the NE Atlantic. Boundaries between major oceanic crustal domains were formed when the European Plate changed its absolute motion direction, probably caused by successive adjustments along its southern boundary.

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SUMMARY:A three-dimensional gravity model of the North Pennine batholith is interpreted to indicate that it comprises five contiguous steep-sided plutons. The North Pennine batholith was previously referred to as the Weardale Granite, but this term is now restricted to the largest, most central pluton, which was proved by the Rookhope Borehole in 1961. The surrounding plutons are the Tynehead and Scordale plutons in the west, and the Rowlands Gill and Cornsay plutons in the east. A new U-Pb zircon age of 399.3 ± 0.7 Ma demonstrates an unequivocal Early Devonian (Emsian) age of emplacement for the Weardale Pluton. The similarity of the forms of the four unsampled plutons to the body beneath Rookhope, and to other Devonian granites in Northern England, strongly suggests that they are also of Devonian age. Seismic reflection evidence supports a contrast between relatively deep-seated Devonian granites and tabular Ordovician granites in northern England. The most conspicuous magnetic anomalies over the North Pennine batholith are associated with the Early Permian Great Whin Sill, but there is also evidence of magnetized basement rocks or denser magnetic intrusive phases on the flanks of the non-magnetic, low density plutons. A long-wavelength magnetic low can be explained in part by the granite puncturing a deep magnetic basement, although the demagnetized zone may extend beneath the batholith. A spatial correlation between the vein systems in the Northern Pennine Orefield and the form of the batholith suggests that the granite masses played a significant role in focussing mineralizing fluids into the overlying Carboniferous rocks. The highest temperature mineralization occurs over the Weardale and Tynehead plutons, where there is also the clearest evidence for the channelling of mineralizing fluids through the batholith. The other plutons are generally associated with a lower intensity of mineralization, which occurs on Kimbell et al. N Pennine granite batholith 2 their flanks rather than above their roofs. The Rookhope and Tynehead areas may therefore mark the location of convective 'chimneys' which were important in focussing the fluid circulation responsible for the mineralization. The coincidence of the 'chimney' zones with the minimum of the long wavelength magnetic low suggests that the hydrothermal system may also have played a role in modifying crustal magnetization. [End of Summary]The existence of a granite body concealed beneath the Alston Block in the north Pennines was first suggested on the basis of the zoned distribution of constituent minerals within the area's hydrothermal veins and related deposits (Dunham 1934(Dunham , 1948. A central zone is characterized by high temperature mineral assemblages in which fluorite is prevalent (Fig. 1).This zone is surrounded by lower temperature mineralization dominated by barium minerals.Comparison with the south-west England orefields led Dunham (1934) to speculate that a concealed, 'Variscan'-age granite 'batholith or stock' beneath the orefield centre ge...