Abstract-We combine geological data and ground motion estimates from satellite ERS-1/2 and ENVISAT persistent scatterer interferometry (PSI) to delineate areas of observed natural and anthropogenic geohazards in the administrative area of Greater London (United Kingdom). This analysis was performed within the framework of the EC FP7-SPACE PanGeo project, and by conforming to the interpretation and geohazard mapping methodology extensively described in the Production Manual (cf. http://www. pangeoproject.eu). We discuss the results of the generation of the PanGeo digital geohazard mapping product for Greater London, and analyse the potential of PSI, geological data and the PanGeo methodology to identify areas of observed geohazards. Based on the analysis of PSI ground motion data sets for the years 1992-2000 and 2002-2010 and geology field campaigns, we identify 25 geohazard polygons, covering a total of *650 km 2 . These include not only natural processes such as compaction of deposits on the River Thames flood plain and slope instability, but also anthropogenic instability due to groundwater management and changes in the Chalk aquifer, recent engineering works such as those for the Jubilee Line Extension project and electricity tunnelling in proximity to the River Thames, and the presence of made ground. In many instances, natural and anthropogenic observed geohazards overlap, therefore indicating interaction of different processes over the same areas. In terms of ground area covered, the dominant geohazard is anthropogenic land subsidence caused by groundwater abstraction for a total of *300 km 2 , followed by natural compression of River Thames sediments over *105 km 2 . Observed ground motions along the satellite line-of-sight are as high as ?29.5 and -25.3 mm/year, and indicate a combination of land surface processes comprising ground subsidence and uplift, as well as downslope movements. Across the areas of observed geohazards, urban land cover types from the Copernicus (formerly GMES) EEA European Urban Atlas, e.g., continuous and discontinuous urban fabric and industrial units, show the highest average velocities away from the satellite sensor, and the smallest standard deviations (*0.7-1.0 mm/year). More rural land cover types such as agricultural, semi-natural and green areas reveal the highest spatial variability (up to *4.4 mm/year), thus suggesting greater heterogeneity of observed motion rates within these land cover types. Areas of observed motion in the PSI data for which a geological interpretation cannot be found with sufficient degree of certainty are also identified, and their possible causes discussed. Although present in Greater London, some geohazard types such as shrink-swell clays and ground dissolution are not highlighted by the interpretation of PSI annual motion rates. Reasons for absence of evidence of the latter in the PSI data are discussed, together with difficulties related to the identification of good radar scatterers in landsliding areas.

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In recent decades, industrial activity in the marine environment has dramatically increased. Dense offshore infrastructure combined with an increase in shipping activity creates a complex blend of potential oil pollution and environmental risk. Over the last year, CGG Satellite Mapping, supported by the European Space Agency's business applications, Oil Spill Response Limited and key oil and gas companies, created and managed a SeaScope monitoring demonstration service. SeaScope confirms the presence or absence of slicks around infrastructure; reports on the integrity of operations based on slicks observed; identifies the potential origins of pollution slicks or permitted discharge; and has the ability to distinguish between pollution and natural seepage by using routine satellite monitoring. This paper describes how advances in Earth observation radar combined with AIS (Automatic Identification System), metocean data and experts trained in the interpretation of offshore satellite imagery, can be used to regularly monitor sea surface oil slicks and notify offshore operators of anomalous events within the vicinity of offshore infrastructure and high density shipping areas.