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The Paleocene -Eocene-aged Sele Formation is developed across the basinal region of the Central North Sea. The section comprises a number of deep-marine fan systems that expanded and contracted across the basin floor in response to relative sea-level changes on the basin margin and fluctuating sediment yield off the Scottish landmass modulated by climate and hinterland uplift. Persistent sediment entry points to the basin resulted in the development of discrete axial and transverse fan fairways with a geometry dictated by an irregular bathymetry sculpted by differential compaction across Mesozoic faults, halokinesis and antecedent fan systems. A high-resolution biostratigraphic framework has allowed the evolution of fan-dispersal systems in response to these effects to be tracked across the basin within four genetic sequences. The proximal parts of the fans comprised channel complexes of low sinuosity, high lateral offset, and low aggradation. The development of these systems in a bathymetrically confined corridor of the Central Graben (c. 65 km wide), combined with high sediment supply, resulted in the eventual burial of any underlying relief. The behaviour of sand-rich reservoirs in this region is dominated by the permeability contrast between high-quality channel fairways and more heterolithic overbank regions, with the potential for early water breakthrough and aquifer coning in the channel fairways, and unswept volumes in overbank locations. Compartmentalization of compensationally stacked channel bodies occurs locally, with stratigraphic trapping caused by lateral channel pinch-outs, channelbase debrites, mud-rich drapes and abandonment fines. Towards the southern part of Quadrant 22, approximately 150 km down-palaeoflow, the systems became less confined and in this region are dominated by channel-lobe complexes, which continued to interact with an irregular bathymetry controlled by antecedent fans, mass-transport complexes and halokinesis in the form of rising salt diapirs. Reservoirs in this region are inherently stratigraphically compartmentalized by their heterolithic lithology and compensational stacking of lobes, and further complicated by structuration and instability induced by the diapiric or basement structures needed to generate a trapping structure in these settings.The Sele S1 Unit contains the most areally extensive and thickest deep-water sandstone member of the Sele Formation, namely the Forties Sandstone Member (FSM). The FSM is restricted to the Central Graben, is over 200 m thick along reaches of the SELE FORMATION DEPOSITIONAL SYSTEMS J. ELDRETT ET AL.

This paper deals with the systematic and botanical description of the microfloral elements from the Pliocene S. Pedro da Torre section (NW Portugal) and the description of the palaeoenvironment and palaeoclimate, for use as a correlation attempt with other Pliocene deposits. The S. Pedro da Torre section represents one of the main sites which may help us to understand the vegetation and the paleoenvironment of the Pliocene north-western Iberian Peninsula. Nearly 70 different taxa were indentified (including bryophytes, ferns, gymnosperms and angiosperms), which indicate a palaeowetland setting, dominated by arboreal vegetation that developed under humid and warm climatic conditions. rÉsuMÉ Flore pliocène des dépôts de S. Pedro Da Torre (Minho, NW Portugal). Ce travail concerne la description botanique et systématique d'éléments microfloraux du Pliocène de S. Pedro da Torre (NW Portugal), la caractérisation du paléoenvironnement et du paléoclimat, ainsi qu'une tentative de corrélation avec d'autres dépôts du Pliocène. Cette localité est un site important pour comprendre la végétation et le paléoenvironnement du nord-ouest de la péninsule Ibérique au cours du Pliocène. Près de 70 taxons différents ont été identifiés (bryophytes, fougères, gymnospermes et angiospermes). Ils représentent principalement une paléo-zone humide dominée par une végétation arborescente vivant dans des conditions climatiques chaudes et humides.

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Using a revised chronology, a new palynological study on the late Pliocene (Piacenzian and earliest Gelasian) Rio Maior site of the Tagus Basin in western Portugal has been undertaken from the F98 core. Combining light microscopy and scanning electron microscopy, a total of 127 different pollen and spore taxa have been identified from the Piacenzian Lake and indicate the presence of a subtropical to warm-temperate mixed forest during the majority of the Piacenzian (3.6-2.8 Ma). It is only in the latest Piacenzian (after 2.8 Ma) that progressive extinctions of climate sensitive taxa and a drop in diversity indicate a cooling and drying climate trend that has also been recorded from high-latitude localities. By the earliest Gelasian (2.58 Ma), a low diversity Ericaceae and Pinus dominated vegetation remained. The Piacenzian flora of Rio Maior also shows fluctuations in the presence of climate sensitive taxa and pollen-spore diversity that may be related to Piacenzian glaciations.