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北海北部油气区的储层发育范围很广,自断裂基底至始新世均有发育.主要储层有5套:①二叠系风成或河成砂岩;②三叠系河流相砂岩;③中、下侏罗统河成、三角洲以及边缘海砂岩;④上侏罗统浅海和深海浊流砂岩及砾岩;⑤上白垩统-下古新统白垩和古新统深海浊积扇砂岩.古新世-始新世砂岩成岩作用有限,在3 100 m之下,渗透性逐渐变差,先是由于钾长石的溶解作用,约3 700 m之下伊利石是主要影响因素,约4 000 m之下则是次生石英的影响.主要储集层的分布是北北海油气远景区的重要控制因素.“,”Reservoirs in the northern North Sea Basin range from fractured basement to Eocene deposits.There are five sets of main reservoirs:① the Permian Rottiegeudes aeolian and/or alluvial sandstones;②the Triassic fluvial sandstone;③the Middle and Lower Jurassic fluvial,deltaic and marginal marine sandstone;④the Upper Jurassic shallow marine and deep marine turbidite sandstone and conglomerate;⑤the Upper Cretaceous-Lower Paleocene chalk and Paleocene deep-sea turbidite fan sandstones.It is found that the Paleocene-Eocene sandstone is weak in diagenesis and permeability becomes lower under 3100 m.The dissolution of K-feldspar is a major factor influencing diagenesis and permeability in the shallower part.Then illite becomes the main factor below about 3700 m,and secondary quartz plays a major role in the sequence below 4000 m.Oil and gas accumulation depends on the distribution pattern of reservoirs.