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The sedimentology and sequence stratigraphy of the Upper Jurassic (Upper Oxfordian — Middle Kimmeridgian) Fulmar Formation of the Kittiwake Field, Western Platform of the north Central Graben are investigated through an integrated study of core material and wireline logs. The Fulmar Formation, in this area, comprises largely finegrained sandstones which are intensely bioturbated such that the use of primary sedimentary structures for the identification of depositional environments is impractical. By using the approach of ichnofabric analysis presented here, the information provided by trace fossils can be fully utilized in the formulation of a depositional model for the Fulmar Formation. A depth and substrate-related succession of ichnofabrics was determined for the Fulmar Formation from more complete and progradational successions. This attached shoreface succession extends from a Chondrites ichnofabric (offshore), through Anconichnus (upper offshore), Anconichnus and spreiten burrows and ‘ Teichichnus zigzag ’ (upper offshore-offshore transition zone), bivalve tube ichnofabric (offshore transition zone to lower shoreface), Ophiomorpha irregulaire (lower shoreface), Ophiomorpha nodosa (middle shoreface) to a burrow mottling ichnofabric and associated high-energy laminated sandstones (upper shoreface). Anomalies in this succession form the basis for the identification of bounding surfaces, particularly omission surfaces ( Thalassinoides and Diplocraterion habichi ichnofabrics) and sequence boundaries. The distribution and evolution of the essentially retrogradational succession of the Fulmar sandstones is illustrated by analysis of a detailed core log of well 21/18-3, a general cross section through the Kittiwake Field and an Early-Mid-Kimmeridgian time slice facies distribution map.

Large gas reserves are trapped in the coals of the Middle Jurassic (Callovian) Walloon Subgroup (lower part of the Injure Creek Group) in the Surat Basin, eastern Australia. The series is divided into the Juandah Coal Measures (upper), Tangalooma Sandstone and Taroom Coal Measures (lower).The upper and lower units are locally further subdivided. These economically important coals were deposited in an alluvial plain setting within an interior basin, which has no recorded contemporaneous marine influence. The coals are typically bituminous, perhydrous and low rank with a high volatile content. Despite individual ply (bench) thicknesses typically less than a metre, series of plies or seams of coals up to 10 m thick have historically been tentatively correlated across the entire play area (over 150 km). 2011-043r esearch-articleArticle19X10.1144/petgeo2011-043M. A. MartinWalloon Subgroup sedimentology and stratigraphy

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The Lower Palaeozoic deposits in North Africa are dominated by sandstones and shales which often lack biostratigraphically useful body fossils. Trilobite burrows (Cruziana) partly fill this gap and provide the basis for medium‐resolution stratigraphic interpretations. Several Ordovician‐Silurian ichnostratigraphically significant Cruziana forms have been found and studied in the Kufra Basin (SE Libya), including C. goldfussi and C. furcifera from the Lower Ordovician Hawaz Fm. and a new ichnospecies, C. kufraensis, occurring in transgressive sandstones at the base of the Lower Silurian Tanezzuft Fm. The upper Tanezzuft Fm. and Akakus Fm. typically contain C. acacensis, a form that is characteristic of the Lower Silurian of Northern Gondwana.