【摘要】 随着油气勘探向纵深发展,辽河西部凹陷油气勘探的难度越来越大,现今的勘探面临着复杂的石油地质难题。为了加强西部凹陷的油气精细、立体勘探,提高油气资源的探明率,并借鉴冀东油田、吉林油田和胜利油田油气精细勘探的成果实例,开展西部凹陷的油气精细勘探十分必要,而层序地层格架的建立是油气精细勘探的基础,因而具有十分重要的理论和实践意义。收集了辽河西部凹陷丰富的钻测井资料、地震资料及古生物资料,通过对本区地震剖面上不整合面的识别、古生物化石的等时地层对比、测井曲线组合的突变面识别等,进行层序边界的识别,并运用层序地层学原理,在本区古近系识别出4个二级层序和11个三级层序。在层序界面识别和层序单元划分基础上,通过制作合成记录,建立井震层序地层格架。层序格架内沉积层序整体分布规律为:沉积中心向南迁移,斜坡沉积厚度薄;南厚北薄,洼陷地层齐全;凸起部位地层发育不全。更多还原

【Abstract】 With the development in depth of the oil and gas exploration, the exploration of the Liaohe western depression becomes more and more difficult, and serves as a complex challenge in view of petroleum geology.In order to undertake the fine and three-dimensional exploration of the oil and gas in the western depression and to increase the success rate of exploration, it is necessary to learn the successful exploration experience from Jidong oilfield, Jilin oilfield and Shengli oilfield, and to carry out detailed exploration of oil and gas in the western depression.The establishment of a sequence-stratigraphic framework is essential for the fine exploration of the oil, and of great theoretical and practical significance.Guided with the theory of sequence stratigraphy and based on well drilling, well logging, seismic and palaeophyte data in the interested districts, the paleogene can be divided into 4 second-order sequences and 11 third-order sequences on the basis of the identification of the sequence boundary which is made through unconformity surface recognition in the seismic section, isochronal formation comparison of the palaeontology fossil and mutation surface recognition of the well logging curves.According to the sequence boundary and the division of layer cells, and by using the synthetic seismogram, the sequence-stratigraphic framework of the west depression is established.Sedimentary sequence distribution law in the sequence-stratigraphic framework includes 5 aspects:migrated southward depocenter;thin slope sedimentary;large sedimentary thickness in the south and small sedimentary thickness in the north, a complete formation in the low-lying;and a not completed formation in the heave part.更多还原