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The discovered resourceso fthe NorthS ea petroleum systems totalaround100 billion barrels oil equivalent recoverable.Of these70% occur inthe Jurassic-sourced petroleum systemofthe CentralandNorthern NorthS ea (CNNS). The secondmajor petroleum systemo ccurs int he Southern NorthS ea (the Anglo-Dutch Basin,A DB),c ontains around30% ofthe resources,i sCarboniferous-sourced andg as-bearing.The discovery patterns ofthe resourcesint he two basins areh erea nalysed bycomparisonw ithsomea nalogous basins. The CNNS canbe compared geologically withothero il-proneb asins:S irte, Bohai Wan,G ulfofS uez, Cambay/Bombay,Marib-AlJawfandthe southern part ofthe West Siberianbasin. The ADB canbe compared withg as-proneb asins:P oland, Dnepr-Donets,G ippsland, GulfofT hailand, NW Australia andnorthern West Siberia.The discovery patterns ofthe basins arec ompared witheach otheru sing:. resource growthwithrespecttoexploration wells; . fieldsized istributions; . discovered volumeswithrespecttoexploration wells; . exploration efficiency.Asimple'ranking'based on thesec riteria suggests thatt he CNNS iso fmiddlerankwhilethe ADB is, surprisingly,a lmost 'worst inclass'.

This thesis investigates the performance of a resonant non-linear vibratory, conveyor in which the conveying surface is horizontal and the maximum vertical acceleration is less than the acceleration of gravity.The mechanism by which material transport occurs has been previously established by other workers, and it is known that when the table surface is sinusoidal accurate predictions of transport rate can be made. When the conveyor has a non-linear spring force the displacement waveform can only be calculated with some difficulty.Two experimental conveyors were constructed. In both an unsymmetric non-linear spring characteristic was formed with a stiff 1impa ctt spring on one side of.the vibrating conveyor. Various stiff springs were used, and the gap between the stiff spring and the conveyor in its equilibrium position was variable. One conveyor was for vibration in a horizontal direction and the other allowed vibration at angles of inclination up to 30 0 . The exciting force was applied by an electromagnetic vibrator through a force transducer which allowed accurate measurement of the input force. Analogue computer circuits and digital computer programmes were developed to allow comparison between experiment and theory and to investigate the effect of material load on conveyor performance.It is confirmed that the performance of a linear conveyor is very dependent on tuning, and this is seriously affected when the material load is heavy. By contrast a non-linear conveyor is less dependent on accurate control of-frequency when the material load is negligible, and gives travel rates which are almost independent of material load over wide ranges. U.Good agreement is found between computer results and experimental results, and it is envisaged that computer techniques would be a valuable aid in conveyor design.Expressions are developed for the maximum travel rate which could he obtained in terms of maximum conveyor accieration, the period of the vibration and the coefficient of friction between the conveyor surface and the material to be transported. These results could prove the basis for the design of more sophisticated conveyors. 11].

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