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The Fulmar Field is located on the southwestern margin of the Central Graben in Blocks 30/16 and 30/11 b of the UK sector of the North Sea. The Fulmar Field was discovered 1975 and began producing in 1982 . Currently (2000 the field produces at a rate of 8000 BOPD at a watercut above 90% mainly through the process of rinsing of residual oil. Total STOIIP is 822 MMBBL and ultimate recovery is 567 MMBBL ofoil and 342 BSCF of wet gas. As of the end of 1999, 547 MMSTB ofoil and 325 BSCF of wet gas had been produced. The high recovery factor (69%) of the field is thought to be linked to the combination of well density, large length of reservoir perforated, excellent reservoir quality, sweep by water injection, good pressure support and oil stripping from a secondary gas cap formed early in field life.The Fulmar Field is a small triangular, partly eroded domal anticline with steeply dipping flanks, located on a fault terrace within the western margin of the South West Central Graben at a depth between 9900 and 11 500 ft TVDss. The field has been shaped by three major tectonic processes: (1) halokinesis, (2) syndepositional reactivation of Caledonian basement faults; and (3) syndepositional through post-depositional displacements along the nearby Auk Horst Boundary Fault. The reservoir consists of thick Upper Jurassic, shallow marine, very bioturbated sandstones of the Fulmar Formation overlain by the deeper marine Ribble Sands interbedded within the Kimmeridge Clay Formation. Reservoir seal is provided by the Kimmeridge Clay in the west and Upper Cretaceous chalks which unconformably overlie the Fulmar Formation in the east. The reservoir section has been lithostratigraphically subdivided into six reservoir units and 24 sub-units. Integration of bio-and lithostratigraphic data has led to a sequence stratigraphic model of the Jurassic succession in the Fulmar Field. In total four depositional sequences are identified, which progressively onlap Triassic basement towards the southwest. The older Jurassic sequences are characterized by rapid progradation of shoreface sands, whereas aggradation of thick sediment packages is typical of the younger intervals. This change of depositional architecture is linked to syndepositional reactivation of basement faults. Major transgressive intervals form intra-reservoir barriers or baffles to flow. Facies changes (Mersey-Clyde Sands) from proximal to distal facies are abrupt and are also linked to basement faults.

ABSTRACT. An articulated dragon¯y from the Lower Jurassic Posidonia Shale of northern Switzerland is described. The specimen is assigned to Liassogomphus brodiei (Buckman). This is the ®rst description of an articulated member of the family Liassogomphidae, hitherto known from isolated wings only. Almost identical wings were previously described as Phthitogomphus angulatus (Handlirsch) and Palaeogomphus propinquus (Bode). The latter is now treated as synonymous with Liassogomphus brodiei, and the genus Palaeogomphus Handlirsch is therefore a junior synonym of Liassogomphus Cowley. The structures of the head, eyes, thorax, legs, and ®rst segments of the abdomen con®rm the state of the Liassogomphidae within the Anisoptera (or Pananisoptera) and point perhaps to a close relationship of the Liassogomphidae to the extant family Aeshnidae. This has already been stated previously based on wing venation patterns alone. The taphonomy of dragon¯ies in marine settings is brie¯y addressed. Only a combination of several exceptional circumstances led to the fossilization of this remarkable fossil.