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Figure 1. Examples of digital survey methods to capture spatially referenced outcrop data; (a) Real-Time Kinematic (RTK) GPS, stationary base-station. In the field, differential GPS locates the base station with a global accuracy of ca. 0.5m; this is improved by post-processing to ca. 10mm; (b) Two RTK GPS rover-units. A positional fix relative to the base-station can be made instantaneously, typically with a precision of ca. 10mm; (c) MDL LaserAce 300 laser-ranging device, with hand-held PDA data-logger. The laser-ranger is used to record the precise position of individual observations and structural measurements made on the outcrop, relative to the instrument. RTK GPS is then used to measure the accurate location of the instrument, and thus the absolute position of all its relative measurements; (d) terrestrial laser-scanning using MDL Quarryman The data captured includes x,y,z position and intensity information for each point scanned, and the resultant grey-scale laser-scan point-cloud can be imported into most 3D visualisation tools; (e) false-colour laser-scan point-cloud from MDL scanner, imported into GoCad; (f) Riegl LMS-Z360i laser-scanner, with top-mounted high resolution digital camera (to give true-colour point cloud data) and RTK GPS unit to record precise scanner location; (g) true-colour point cloud data from Riegl LMS-Z360i scanner. Locations: (a) analysis of fault-related folding, Howick, NE England (Pearce et al., 2006); (b) segmented faults, Lamberton, SE Scotland; (c) study of onshore analogues for Devonian clastics of West Orkney Basin, Kirtomy, N Scotland; (d-e) faulting in Carboniferous sandstone/shale sequence, NE England; (f-g) study of fractured carbonates, Flamborough, E England.