This paper describes, from field exposures, temporary excavations and borehole core, the pedogenically altered fluvial deposits found in the UAE termed the Barzaman Formation. This formation comprises a sequence of rocks dominated by variably cemented conglomerates thought to be middle Miocene to Pliocene in age. The sequence is interpreted as an alluvial fan succession (or "bajada") laid down in response to uplift and erosion of the Hajar Mountains. A ground model for this formation is described to explain the distinct lithological features of the formation, comprising terrestrial fluvial and alluvial plain deposits that have been modified by cementation and dolomitisation, duricrust formation and pedogenic processes during arid periods over repeated climatic cycles. Four principle lithologies thus typically occur as a rhythmic alternation of a basal conglomerate (composed predominantly of clasts of ophiolite and chert) overlain by an irregular bed of white conglomerate and "calcisiltite" and passing upwards into a pale grey to green clay and siltstone "breccia". The white conglomerate and calcisiltite largely represent deposits of dolomite-palygorskite duricrust. The well established Clarke & Walker (1979) descriptive scheme currently used for describing the formation is reviewed and a simple visual descriptive lithological classification proposed. The classification is described in terms of the three principal lithological components visible in hand specimen: mottled white calcisiltite matrix/cement, palygorskite rich marl and clasts derived from the Oman Mountains (gabbro, chert and weathered ultramafic rock). Data on the mineralogy and microstructure of the rock constituents is also presented and some implications for geotechnical characterisation of the formation briefly discussed.

This paper examines recent developments in remote sensing applied to civil engineering projects, particularly those involving terrain analysis of linear infrastructure features. Applications using high-resolution satellite data (e.g. IKONOS and Quickbird), laser altimetry and digital elevation models (DEMs) are discussed. Guidelines are given for the stages of a project in which different remote sensing techniques could be employed. The case is also made for greater use of archive remote sensing datasets, which can be a valuable source of information about landscape dynamics.

No abstract

No abstract