Ichnology of a dolomitized raised reef: Hopegate Formation, Jamaica (Upper Pliocene)

Abstract

Abstract The Upper Pliocene Hopegate Formation of north central Jamaica is a dolomitized raised reef. Hitherto, its palaeontology has been largely ignored because of the poor preservation; the Hopegate Formation is highly karstified, well indurated and fossils are commonly preserved as molds. However, moldic preservation has enhanced the common borings. Ichnotaxa identified from this formation include Entobia ovula? Bromley and d’Alessandro; Entobia ispp.; Gastrochaenolites isp. cf. G. torpedo Kelly and Bromley; Gastrochaenolites pickerilli Donovan; Gastrochaenolites ispp.; Oichnus simplex Bromley; Rogerella isp. cf. R. lecontrei Saint-Seine; Talpina isp. cf. T. hirsuta Voigt and Uniglobites flomerata (Morris). There are more specimens of Entobia than all other ichnotaxa combined. Comparison with other Neogene formations or members in the Antilles demonstrates that the association Entobia + Gastrochaenolites + Oichnus is near-ubiquitous. Caulostrepsis Clarke, which is common in modern shallow water environments in association with Entobia and Gastrochaenolites, is less common in the ancient associations of the Antilles.