The Triassic–Jurassic junction at Golspie, inner Moray Firth Basin

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Abstract
Synopsis: The Dunrobin Bay Formation is redefined to include as its basal member the Dunrobin Pier Conglomerate which was previously assumed to be unfossiliferous and tentatively dated as Rhaetian (Late Triassic). Temporary exposures of organic-rich horizons within the deposit have yielded assemblages of palynomorphs dominated by pollen grains of the Circumpolles group. Kraeuselisporites reissingeri (Harris), Converrucosisporites luebbenensis Schulz, and Pilospora sp. cf. P. parva (Cookson and Dettmann) are among the more common associated forms. Although taxonomically impoverished, the overall composition of the palynoflora suggests a ?latest Rhaetian to Hettangian (Early Jurassic) age and accumulation in a freshwater environment. The conglomerate is interpreted as the deposits of braided alluvial streams on an alluvial fan derived from vegetated areas to the southwest. It is unconformable upon Triassic calcretes and silcretes which were formed in a hot, fairly arid climate. The hiatus between the two units represents a period of local erosion before deposition of the conglomerate during a period of increased rainfall.