The Grampian and Appin groups of the southwestern Monadhliath Mountains form the earliest known syn-rift sequences of the Scottish central Highlands. They were likely to have formed in an intracontinental setting and represent deposition of mixed clastic and carbonate shallow and deep marine strata. The Grampian Group of the southern Monadhliath Mountains was deposited during a period of initial basin rifting (NW–SE extension) followed by a phase of thermal subsidence. Syn-rift sediments comprise a 2.5–6 km thick turbidite system. Thermal subsidence brought about the basinward progradation of shallow marine shelf sediments resulting in the infilling of pre-existing basin topography. The overlying Appin Group commenced with deposition of a shallow marine sequence alternating between nearshore tidal sand and offshore mud deposition. This formed in response to renewed rifting and concomitant subsidence. Accelerated rifting resulted in localized footwall uplift and erosion while sedimentation continued in the hanging-wall areas. Resultant subsidence, perhaps partly thermally driven, caused gradual basin widening and produced an onlapping marine sequence. There followed a period of progressive clastic deprivation when carbonates were precipitated, and at the onset of anoxic conditions, deposition of organic muds. The fundamental structural elements responsible for the formation of the Grampian and Appin group basins were also influential in the orogenic evolution of the basin-fill. Half-graben fills were deformed to produce regionally extensive folds such as the Stob Ban–Craig a’ Chail Synform.

Digital processing and image-based display techniques have been used to generate contour and shaded-relief maps of Belgian aeromagnetic data at a scale of 1:300000 for the whole of Belgium. These highlight the important anomalies and structural trends, particularly over the Brabant Massif. North and vertically illuminated shaded-relief plots, enhanced structural belts trending west-east to northwest-southeast in the Brabant Massif and west-east to southwest-northeast in the core of the Ardennes. The principal magnetic lineaments have been identified from the shaded-relief plots and tentatively correlated to basement structures. Most short lineaments are correlated with individual folds while the more extensive lineaments are correlated with large scale fault structures. Magnetic highs within the Brabant Massif are attributed to folded sediments of the Tubize Group. The magnetic basement in the east of Belgium is sinistrally displaced to the north by an inferred deep NNW-SSE crustal fracture. The Bouguer anomaly map of Belgium identifies the Ardennes as a negative area, and the Brabant Massif as a positive area, with the exception of a WNW-trending gravity low in its western part. The southern margin of the Brabant Massif is defined by a steep gravity gradient coincident with the Faille Bordiere (Border Fault). Trial modelling of the gravity and magnetic data, carried out along profiles across the Brabant and Stavelot massifs, has identified probable acid igneous intrusions in the western part of the Brabant Massif, and a deep magnetic lower density body underlying the whole Ardennes region, which is thought to be a distinctive Precambrian crustal block.

Long term planning for flood risk management in coastal areas requires timely and reliable information on changes in land and sea levels. A high resolution map of current changes in land levels in the London and Thames estuary area has been generated by satellite-based persistent scatterer interferometry (PSI), aligned to absolute gravity (AG) and global positioning system (GPS) measurements. This map has been qualitatively validated by geological interpretation, which demonstrates a variety of controlling influences on the rates of land level change, ranging from near-surface to deep-seated mechanisms and from less than a decade to more than 100,000 years' duration.During the period 1997 to 2005, most of the region around the Thames estuary subsided between 0.9 and 1.5 mm a -1 on average, with subsidence of thick Holocene deposits being as fast as 2.1 mm a -1 . By contrast, parts of west and north London on the Midlands Microcraton subsided by less than 0.7 mm a -1 , and in places appear to have risen by about 0.3 mm a -1 . These rates of subsidence are close to values determined previously by studies of Quaternary sequences, but the combined GPS, AG and PSI land level change data demonstrate a new level of local geological control that was not previously resolvable.

Metasedimentary rocks of the Neoproterozoic Grampian and Appin groups exposed in the Glen Roy district (Monadhliath Mountains, Scotland) were strongly folded during an initial progressive tectonothermal event of the Caledonian orogeny. The attitude and style of the first folds varies from open, upright NE-trending structures in the west (e.g. the Appin Synform) to recumbent NW-facing nappes in the east (e.g. the Treig Synform). These early nappes occur only south of the Corrieyairack Complex and their amplitude decreases towards the NW. Ductility contrasts induced sliding such as that locally recorded along the Grampian-Appin group lithostratigraphical boundary. Subsequently the early structures were deformed by tight, upright ‘D2’ folds. NW-thrusting along the Eilrig Shear Zone, during ‘D2’, is interpreted as occurring in response to a transfer of bulk transport to deeper structural levels relative to ‘D1’. Prograde metamorphism accompanied deformation, with the thermal peak in the Glen Roy district (T = 500–600 °C; P = 7.0–8.0 kbar) coinciding with ‘D2’ folding. It is suggested that the regional variation in the style of deformation was controlled, at least in part, by pre-existing major structures, most notably fundamental, transverse basement lineaments. Temporal changes in the style of deformation occurred in response to changing crustal architecture during progressive deformation. The study demonstrates the diachronous nature of deformation and also illustrates how its is possible to preserve areas with simple deformation histories in the centre of a major orogenic belt.

Journal of Flood Risk Management AbstractLong term planning for flood risk management in coastal and estuarine areas requires timely and reliable information on changes in land and sea levels. In this paper we describe how we have produced a detailed, high resolution map of current changes in land levels for the Thames region, and carried out a new assessment of the changes in sea level relative to the land along the Thames Estuary over the past few decades / past century. We conclude the paper by considering the potential benefits of extended monitoring for the long term planning of flood and coastal defences in that region.