A ground‐penetrating radar survey of aeolian dunes in the Al Liwa area of Abu Dhabi reveals a variety of dipping reflectors which are interpreted as primary sedimentary structures. The interpretation of the radar profiles has been confirmed by bulldozing trenches through the study area and comparing logged sections in the trenches with the radar profiles. NNW— SSE‐orientated radar profiles, approximately parallel to the prevailing wind direction, show two sets of dipping reflectors which are interpreted as sets of cross‐stratification and second‐ and third‐order bounding surfaces. Radar profiles orientated WSW—ENE across the prevailing wind direction are dominated by concave‐up reflectors which are interpreted as trough‐shaped scours and sets of trough cross‐stratification produced by oblique progradation of barchanoid dunes. Nested troughs, with small sets of trough cross‐stratification within larger troughs, may be due to reactivation following wind reversal, or the superposition of small dunes on larger dunes and the fill of large dune troughs by smaller dunes. Convex‐upwards reflectors are interpreted as linear spurs on the convex portions of sinuous dunes or erosional remnants between troughs. Overall there is a tendency for the larger second‐order bounding surfaces to dip downwind, which confirms Brookfield's ideas of the relative migration paths of dunes and draa.
FMS (Formation MicroScanner) electrical images in a single well from a familiar, deep marine North Sea Palaeogene section are illustrated. More than 900 m of good quality images were acquired through an interval from the Palaeocene Ekofisk Formation to the Eocene Grid Formation in a well from the centre of the South Viking Graben, Norwegian sector. The information that was obtained from these images is illustrated and discussed in terms of lithology, sedimentary structures, stratigraphy and petrophysics. The information on this deep marine, mainly gravity deposit succession, is considerably enhanced using image interpretation. Lithological information includes an improved net-to-gross ratio and an understanding of lithological heterogeneities. Sedimentary structure information includes the geometrical and lithological characterization of slumped intervals and a detailed description of evolving gravity deposit sequences. In terms of stratigraphy, illustrative images are shown of the Balder, Lista and Sele Formations. Some of the key surfaces of the Palaeogene interval, used for correlation and sequence stratigraphy, are shown in detail, especially the surface at the base of the Balder Formation and the boundary between the Lista and Sele Formations. The effect of hydrocarbons on the images is illustrated and used qualitatively in petrophysical terms to define the hydrocarbon-water contact.
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