不整合面是叠合盆地的重要油气输导通道,并在很大程度上控制着油气的分布。深入探讨与不整合面有关的隐蔽油气藏类型和不整合面结构对隐蔽油气藏分布、含油气性的影响及其控制作用是目前隐蔽油气藏勘探、成藏机理研究的热点与前沿。二维模型物理模拟实验结果表明:(1)不整合面的风化粘土层是下伏油气藏良好的封盖层;(2)受物性、非均质性及连通性影响,底部半风化岩层可成为油气运移的有效输导层或侧向封堵层;(3)层间断层的存在沟通了不整合面底部半风化岩层和项部底砾岩层,构成了油气运移的高效“双通道”输导网络,即在不整合面上、下均可形成岩性、地层或复杂型隐蔽油气藏。
Unconformity surfaces are important hydrocarbon conductive channels for superposition basins and dominantly control the hydrocarbon distribution. The highlight and leading focus of elusive reservoir exploration and hydrocarbon genesis analysis are the discussion about the influences and control of the types of elusive reservoirs related to unconformity surfaces and unconformity structures on the distribution and properties of elusive reservoirs. The result of 2-demension model physical simulation experiment indicates that ( 1 ) the decomposed clay layers of unconformity surface are good sealing cap rock for underlying reservoirs; (2) the bottom partial-decomposed rock layers would become effective conducting channels or lateral sealing zones during hydrocarbon migration, subjected to physical property, anisotropy and connectivity; (3) the bottom partial-decomposed rock layers and the upper basal conglomerate are connected by the faults existed inter layers, which composed an effective "double channels" conductive network for hydrocarbon migration, in other words, the lithologic, stratigraphic and complex types of elusive reservoirs might exist above or under the unconformity surfaces.