Abstract Fault-related dolomite subsurface reservoirs are formed from fluid circulation that results in significant transformation of the reservoir properties. The geometry and internal organization of such dolomitic reservoirs remain difficult to image with seismics alone. A multi-scale approach is essential to understand and predict the diagenetic processes that control the exact 3D morphology of the dolomite with spatial precision and true dimensions, and consequently the reservoir properties. In this context, we propose an analytical workflow including field work, LIDAR scanning and numerical geology applied to dolomite outcrops in Mesozoic carbonates (SE France). The exposed dolomite-limestone contact exhibits sinuous, irregular and convolute shapes, which are either fault-parallel, bedding-parallel or chaotic. To characterize this complex distribution, we performed LIDAR scanning on 500 m x 150 m cliffs and road cuts with 4.5 cm to 1–1.5 cm average point spacing. The cloud is composed of 22 millions points comprising X, Y, Z, intensity, red, green, and blue attributes. Digitization of the limestone-dolomite boundary was performed in RiscanPro and GOCAD environments, for extracting the true 3D geometry of the dolomite body for further geostatistical and 3D facies modelling. This approach captures the large-scale geometry of the dolomite bodies. However, single RGB or intensity properties do not unequivocally reproduce small-scale (below ∼ 1 m) heterogeneities of the late diagenetic dolomite. Color changes induced by weathering or climatic conditions are of the same size range as the small-scale heterogeneities, thus they are not unique to allow automated tracking on the point set. As a result, the workflow remains time-consuming, and further work is needed to allow calibration of the LIDAR data points with mineralogy.

Abstract The Variscan Orogeny is the major Middle to Late Palaeozoic tectonometamorphic event in Central Europe representing the final collision of Gondwana with the northern continent of Laurussia. Thus, large areas of the pre-Permian basement consist of continental crust that achieved its final form during this event. The Variscan Orogeny represents the European version of the evolution of the supercontinent of Pangaea at the end of the Palaeozoic. Western Pangaea, including the Variscan Orogen, formed as a result of the continuous closing of the oceanic domains between Gondwana and Laurussia (Old Red Continent: North American Craton + East European Craton + Avalonia). Coeval accretion of large volumes of oceanic crust along the Eastern Uralides and Altaids (Sengör et al. 1993) as well as Precambrian continental crust (e.g. Siberia and Kazakhstan) along the eastern edge of Laurussia represents the formation of eastern Pangaea. Following the Permian termination of collisional tectonics along western Pangaea there was ongoing convergence in the Asian part until the Early Mesozoic, as demonstrated by the evidence of Triassic continental subduction within the Qinling–Dabie–Sulu Belt between the northern Sino- Korean Craton and the southern Yangtze Craton ( Ernst 2001 , and references therein). Despite the occurrence of both pre- and synorogenic subduction processes within the area of the Variscan Orogen, the accretion of juvenile crust plays a relatively minor role in terms of the crustal evolution of the region. Recycling of basement formed during the Neoproterozoic–Early Cambrian Cadomian Orogeny and its Early Palaeozoic cover can be considered to be one