An integrated sequence stratigraphic study based on outcrop, core and wireline log data documents the combined impact of Cretaceous eustacy and oceanic anoxic events on carbonate shelf morphology and facies distributions in the northern Gulf of Mexico. The diverse facies and abundant data of the Comanche platform serve as a nearly complete global reference section and provide a sensitive record of external processes affecting Cretaceous platform development. Regional cross-sections across the shoreline to shelf-margin profile provide a detailed record of mixed carbonate-siliciclastic strata for the Hauterivian to lower Campanian stages (ca 136 to 80 Ma). The study window on the slowly subsiding passive margin allows the stratigraphic response to external forcing mechanisms to be isolated from regional structural processes. Three second-order supersequences comprised of eight composite sequences are recognized in the Valanginian-Barremian, the Aptian-Albian and the Cenomanian-Campanian. The Valanginian-Barremian supersequence transitioned from a siliciclastic ramp to carbonate rimmed shelf and is a product of glacial ice accumulation and melting, as well as variable rates of mid-ocean ridge volcanism. The Aptian-Albian supersequence chronicles the drowning and recovery of the platform surrounding oceanic anoxic events 1a and 1b. The Cenomanian-Campanian supersequence similarly documents shelf drowning following oceanic anoxic event 1d, after which the platform evolved to a deep-subtidal system consisting of anoxic/dysoxic shale and chalk in the time surrounding oceanic anoxic event 2. Each period of oceanic anoxia is associated with composite sequence maximum flooding, termination of carbonate shelf sedimentation and deposition of condensed shale units in distally steepened ramp profiles. Composite sequences unaffected by oceanic anoxic events consist of aggradational to progradational shelves with an abundance of grain-dominated facies and shallow-subtidal to intertidal environments. Because they are products of eustacy and global oceanographic processes, the three supersequences and most composite sequences defined in the south Texas passive margin are recognizable in other carbonate platforms and published eustatic sea-level curves. Maraca Lisure A g u a rd ie n te Apon Rio Negro M o rr o n e d i P a c e n tr o Va lle de ll' In fe rn o T r e G r o t t e Cima Dell Murelle

Abstract. Analysis of cored sections from the Central North Sea Basin, boreholes from the onshore Netherlands and onshore sections from the UK and Germany has enabled a major reappraisal of Lower Cretaceous nannofossil datums. The Lower Albian to Upper Barremian interval has, in particular, been comprehensively amended. Five new species, Crucibiscutum bosunensis sp. nov., Crucibiscutum ryazanicum sp. nov., Lithraphidites houghtonii sp. nov., Seribiscutum dentatum sp. nov., Staurolithites palmula sp. nov. and one new sub-species, Biscutum constans cavum ssp. nov. are described.

Abstract. Analysis of abundant, diverse and well-preserved Albian nannofloral assemblages from onshore English sections has enabled a high-resolution nannofloral zonation to be developed with the construction of sixteen zones. The results are correlated with the ammonite zonation.Five new species, Acaenolithus viriosus sp. nov., Staurolithites rotatus sp. nov., Staurolithites canthus sp. nov., Bownia glabra sp. nov. and Calculites percernis sp. nov. are described.

Facies belts exhibit a back-stepping trend towards the London Brabant/ Rhenish Massif through the Early Cretaceous. The overall eustatic sea-level rise was punctuated by short-term tectonic events identified either as localised or North Sea wide in extent. The biostratigraphically constrained sequences have, for the first time, allowed a detailed calibration of tectonic and eustatic events on a North Sea scale. The most extensive database available to any North Sea Cretaceous study was available to the authors together with a comprehensive suite of new high-resolution biostratigraphy and sedimentology. This has allowed unique insights into provenance, depositional environment, extent of sequence stratigraphical events and the degree to which unconformities have been tectonically accentuated.