Altan Uul and Nemegt Uul are mountain ranges in southern Mongolia containing polydeformed Mid- to Late Palaeozoic sedimentary, volcanic and metamorphic rocks uplifted at a restraining bend along the Gobi–Tien Shan left-lateral strike-slip fault system. Altan and Nemegt Uul contain part of an intra-oceanic island arc that was active during the Carboniferous. Thrust-bound sequences of highly fractured pillow basalt, cumulate gabbro, peridotite, serpentinite and jasperoid occur directly north of the arc rocks in at least three discrete belts and are interpreted to be fragments of an ophiolite. Metamorphosed marine sediments that have undergone intense contractional strain lie north of, and structurally below, the ophiolitic rocks. The gabbros within the ophiolitic sequences have undergone prograde metamorphic reactions consistent with an ocean-floor environment, and trace element analyses are similar to those from cumulate gabbros of the Oman ophiolite. Combined field and petrological evidence suggests that there is an east–west-trending south-dipping Late Carboniferous suture in Altan and Nemegt Uul that may be regionally correlated in the southern Gobi Altai region. This proposed suture represents a new and important tectonic boundary between tectonostratigraphic terranes in southern Mongolia, requiring modification of existing models of Late Palaeozoic terrane accretion in the Central Asian Orogenic Belt.

Seismic imaging beneath shallow (<5 km) Palaeogene basaltic volcanic successions on the Faroe–Shetland Margin is very challenging with conventional seismic methods. Consequently, the interpretational uncertainty that surrounds the sub-basalt structure of the region is a major source of exploration risk. This study uses gravity and magnetic data in conjunction with seismic data to map the sub-basalt structure of the Faroe–Shetland Basin and model the crustal architecture of this part of the Atlantic margin. Four crustal types are recognized using gravity data: oceanic, intruded transitional, stretched continental and normal continental crust. Map-based interpretation of the gravity and magnetic data helps redefine the basins, highs and faults in the region. The structural interpretation suggests that the boundary between normal and stretched continental crust is coincident with the long-lived left-lateral ‘West Shetland Shear Zone’, which partitioned strain during rifting of the margin. 2D/2.5D gravity and magnetic models are shown for two seismic profiles from the PGS FSB MegaSurveyPlus. The models suggest highly thinned crust, which was intruded by mafic magma beneath the Flett sub-basin, and an asymmetry to the rifting, which is consistent with a process of Wernicke simple shear.

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A multi-proxy provenance study of Late Carboniferous to Middle Jurassic sandstones from the eastern Sverdrup Basin was undertaken employing optical petrography and heavy mineral analysis, chemical analysis of apatite, garnet and rutile grains, as well as detrital zircon U–Pb geochronology and Hf isotope analysis. Late Carboniferous to Middle Jurassic strata on the southern basin margin are inferred as being predominantly reworked from Silurian to Devonian strata within the adjacent Franklinian Basin succession. Higher-grade metamorphic detritus appeared during Middle to Late Triassic times and indicates exhumation and erosion of lower (Neoproterozoic to Cambrian) levels within the Franklinian Basin succession and/or a direct detrital input from the Canadian-Greenland Shield. The provenance of northern-derived sediments is more enigmatic owing to the subsequent opening of the Arctic Ocean. Northern-derived Middle Permian to Early Triassic sediments were likely derived from proximal areas of the Chukotkan part of the Arctic Alaska-Chukotka microplate. Late Triassic northern-derived sediments have different detrital zircon U–Pb age spectra from Middle Permian to Early Triassic ones and were likely derived from the Uralian orogenic belt and/or the Arctic Uralides. The loss of this sand input during latest Triassic times is interpreted to reflect drainage reorganisation farther upstream on the Barents Shelf. Middle Jurassic sands in the northern and axial parts of the basin were largely reworked from local northern-derived Late Triassic strata. This may have been facilitated by rift flank uplift of the northern basin margin in response to rifting in the adjacent proto-Amerasia Basin.

This volume explores how structural geology can be applied to industrial activities. It includes case studies that exhibit the state of the art and provides an overview of current and future trends in structural geology. The constituent papers cover a wide range of topics, including regional tectonics; trap and prospect definition; fault, fold and fracture analysis; seal analysis; interpretation of geophysical, borehole, core and outcrop data. The volume demonstrates how structural concepts ultimately create value and how academic institutions, specialist consultants and operating companies work together at a variety of scales and in varied geological settings to explore for and produce natural resources for the economic benefit of society.